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ESP Timelines

Comparative Timelines

The ESP Timeline (one of the site's most popular features) has been completely updated to allow the user to select (using the timeline controls above each column) different topics for the left and right sides of the display.

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1540

image Georg Joachim Rheticus publishes De Libris Revolutionum Copernici Narratio Prima in Danzig, an abstract of Copernicus' as yet unpublished De revolutionibus orbium coelestium and the first printed publication of Copernican heliocentrism.

Valerius Cordus discovers and describes a method of synthesizing ether ("oleum dulci vitrioli") by adding sulfuric acid to ethyl alcohol.

Publication in London of the first printed book in English on obstetrics, The Byrth of Mankynde, a translation attributed to Richard Jonas from Rösslin's De partu hominis. It will continue to be issued in new editions for more than a century.

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1541

image Gerardus Mercator makes his first terrestrial globe, for Charles V, Holy Roman Emperor.

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1542

image Leonhart Fuchs publishes his new herbal De historia stirpium commentarii insignes in Basel. It was illustrated by: Albrecht Meyer, who made drawings based on the actual plants; Heinrich Füllmaurer, who transferred the drawings to woodblock; and Vitus Rudolph Speckle, who cut the blocks and printed the drawings.[1] It covers about 497 plants and has over 500 woodcut illustrations. Over 100 of the plants in the book were first descriptions.[2][3] The University of Glasgow states that it is considered a landmark work in its field.[3] Stanford University Press considers it one of the best illustrated books of all time and a masterpiece of the German Renaissance.[4] It set a new standard for accuracy and quality, as well as being the first known publication of plants from the Americas, such as pumpkin, maize, marigold, potato, and tobacco. Plants were identified in German, Greek, and Latin, and sometimes English.[5] The book was initially published in Latin and Greek and quickly translated into German.[6] Just during Fuchs' lifetime the book went through 39 printings in Dutch, French, German, Latin, and Spanish and 20 years after his death was translated into English.[3]

image Jean Fernel publishes De naturali parte medicinae, presenting human physiology as integral to the study of medicine.

In a brief work titled On Meteorology, Fausto da Longiano argues that Noah's flood "cannot have been universal, according to natural reasons," and endorses a 36,000-year cycle of Earth history accepted by some other scholars.

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1543

image De revolutionibus orbium coelestium (On the Revolutions of the Heavenly Spheres) by the Renaissance astronomer Nicolaus Copernicus is published. The book presents the notion that the Earth revolves around the sun (a heliocentric theory) as opposed to Ptolemy's geocentric system (the Earth at the center of the universe), which had been widely accepted since ancient times.

image Andreas Vesalius (Andries van Wesel) publishes the anatomy treatise De humani corporis fabrica (On the Workings of the Human Body).

Niccolò Fontana Tartaglia publishes a translation of Euclid's Elements into Italian, the first into any modern European language.

image Robert Recorde publishes The Grounde of Artes, teaching the Worke and Practise of Arithmeticke, both in whole numbers and fractions, one of the first printed elementary arithmetic textbooks in English and the first to cover algebra. It will go through around forty-five editions in the following century and a half. In this work, the use of the equal sign ("=") is introduced.

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1544

image Orto botanico di Pisa botanical garden established by Cosimo I de' Medici, Grand Duke of Tuscany, under the direction of Luca Ghini, who also creates the first herbarium.

William Turner's Avium praecipuarum, quarum apud Plinium et Aristotelem mentio est, brevis et succincta historia is published in Cologne, the first printed book devoted entirely to ornithology.

Georgius Agricola publishes De ortu et causis subterraneorum, laying the foundations of modern physical geology.

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1545

Thomas Phaer publishes The Boke of Chyldren, the first book on paediatrics written in English.

image Gerolamo Cardano publishes his algebra text Ars Magna, including the first published solutions to cubic and quartic equations.

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1546

German minerologist Georgius Agricola publishes De Natura Fossilium (On the Nature of Fossils), the first published paleontological treatise.

image Girolamo Fracastoro, in his De Contagione et Contagiosis Morbis (published in Venice), discusses the transmission of infectious diseases and gives the first description of typhus.

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1547

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1548

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1549

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1550

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1551

Publication of Erasmus Reinhold's ephemeris (collection of astronomical tables), the Tabulae Prutenicae, helping to disseminate Copernican methods of astronomical calculation.

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1552

image Cornelius Gemma publishes the first illustration of a human tapeworm.

Thierry de Héry publishes La Méthode Curatoire de la maladie vénérienne vulgairement appelée grosse Vérole et de la diversité de ses symptômes, the first work in French on syphilis.

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1553

Publication in Spain of Libro del Exercicio, considered the first book on the benefits of physical exercise for health.

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1554

image Guillaume Rondelet publishes a volume on Mediterranean fish — De Piscibus — and includes the assertion that glossopetrae, or tongue stones, resemble shark teeth. The hypothesis attracts little attention.

Roman naturalist Ippolito Salviani publishes History of Aquatic Animals.

Venetian mathematician Giambattista Benedetti publishes two editions of Demonstratio proportionum motuum localium, developing his new doctrine of the speed of bodies in free fall.

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1555

image Pierre Belon publishes L'Histoire de la nature des oyseaux, a pioneering work in the comparative anatomy of birds.

image The first edition of Alessio Piemontese's Secreti is published, listing about 350 medical recipes along with observations of nature. The publisher, Girolamo Ruscelli, will later claim authorship. Enormously popular, the book will total 104 editions through 1699.

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1556

image Great Comet of 1556 becomes visible in Europe. The comet, known as C/1556 D1 in modern nomenclature, appears to have been seen in some places before the end of February; but it was not generally observed until the middle of the first week in March. Its apparent diameter was equal to half that of the Moon, and the tail resembled " the flame of a torch agitated by the wind," — an expression doubtless referring to the coruscations which are sometimes visible in the tails of comets

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1557

French surgeon Ambroise Paré, at the Battle of St. Quentin, notes that certain maggots assist the healing of wounds.

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1558

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1559

image Jean Nicot, French ambassador to Portugal 1559–61, describes the medicinal properties of tobacco which he introduces in the form of snuff to the French court. The plant was also an instant success and soon many of the fashionable people of Paris began to use the plant, making Nicot a celebrity. The tobacco plant, Nicotiana, also a flowering garden plant, was named after him by Carl Linnaeus, as was nicotine.

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1560

A total solar eclipse visible in Europe occurred on August 21. The prediction of this solar eclipse helped to inspire Tycho Brahe's (1546–1601) interest in astronomy at the age of 13. The announcement of this forthcoming eclipse in France caused many Frenchmen to panic, fighting one another to be next in line at the confessional. One beleaguered parish priest tried to calm the populace by announcing that since there were so many waiting to confess, a decision had been made to postpone the eclipse for two weeks.

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1561

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1562

image Diego Gutiérrez and Hieronymus Cock published the map Americae Sive Quartae Orbis Partis Nova Et Exactissima Descriptio (A New and Most Exact Description of America or The Fourth Part of the World). The map (an ornate geographical map of the Americas) encompasses the eastern coast of North America, the entire Central and South America and parts of the western coasts of Europe and Africa. Americae Sive Quartae Orbis Partis Nova Et Exactissima Descriptio is the earliest scale wall map of the New World and the first to use the name "California".

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1563

Outbreak of bubonic plague — The Black Death — in London kills over 20,000. Plague epidemics ravaged London in 1563, 1593, 1603, 1625, 1636, and 1665, reducing its population by 10 to 30% during those years.

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1564

Galileo Galilei is born born in Pisa (then part of the Duchy of Florence), Italy, on 15 February 1564.

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1565

image Conrad Gessner publishes De Omni Rerum Fossilium ("A Book of Fossil Objects").

Antwerp doctor Samuel Quiccheberg publishes a description of the curiosity cabinet of Hans Jakob Fugger, including items from the animal, vegetable and mineral world.

College of Physicians of London empowered to carry out human dissections.

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1566

image Danish astronomer Tycho Brahe, while studying at the University of Rostock in Mecklenburg, loses part of his nose in a duel with fellow nobleman and relation Manderup Parsberg over a mathematical formula.

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1567

image Paracelsus (Philippus Aureolus Theophrastus Bombastus von Hohenheim) publishes On the Miners' Sickness and Other Diseases of Miners, a pioneering example of occupational medicine.

Fabrizio Mordente publishes a single sheet treatise in Venice showing illustrations of his "proportional eight-pointed compass" which has two arms with cursors that allow the solution of problems in measuring the circumference, area and angles of a circle.

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1568

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1569

image The Mercator projection is first used in Gerardus Mercator's world map Nova et Aucta Orbis Terrae Descriptio ad Usum Navigantium Emendata.

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1570

image London haberdasher Henry Billingsley makes the first translation of Euclid's Elements into English (from the Greek).

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1571

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1572

image A supernova, now designated as SN 1572, is first observed in the constellation Cassiopeia by Cornelius Gemma. Tycho Brahe, who notes it two days later, will use it to challenge the prevailing view that stars do not change.

image Girolamo Mercuriale of Forlì (Italy) writes the work De morbis cutaneis ("On the diseases of the skin"), the first scientific tract on dermatology.

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1573

French surgeon Ambroise Paré publishes the first edition of Des Monstres et Prodiges. At this time, surgeons are not regarded as real doctors, and Paré is roundly criticized for discussing larger issues of medicine and philosophy, considered well beyond his purview.

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1574

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1575

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1576

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1577

image The Great Comet of 1577 (official designation: C/1577 V1) was a comet that passed close to Earth during the year 1577 AD. It was viewed by people all over Europe, including the famous Danish astronomer Tycho Brahe and Turkish astronomer Taqi ad-Din. From his observations of the comet, Brahe was able to discover that comets and similar objects travel above the Earth's atmosphere. The best fit using JPL Horizons suggests that the comet is currently about 320 AU from the Sun (based on 24 of Brahe's observations spanning 74 days from 13 November 1577 to 26 January 1578).

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1578

Li Shizhen completes the first draft of the materia medica Bencao Gangmu.

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1579

image Hieronymus Fabricius discovers the membranous folds that serve as valves in the veins.

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1580

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1581

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1582

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1583

image Andrea Cesalpino publishes De Plantis, ordering plants in families. In his works he classified plants according to their fruits and seeds, rather than alphabetically or by medicinal properties. In 1555, he succeeded Luca Ghini as director of the botanical garden in Pisa.

Agostino Michele publishes On the Magnitude of the Water and of the Earth, calling himself "determined to follow Aristotle and Plato only as much as Moses and Christ allow," and arguing that huge subterranean reservoirs made the universal deluge of Noah's flood possible.

image Thomas Fincke's Geometria rotundi is published, introducing the terms tangent and secant for trigonometric functions.

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1584

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1585

image Michele Mercati establishes one of the first mineralogical curiosity cabinets in Europe. Mercati was a physician who was superintendent of the Vatican Botanical Garden under Popes Pius V, Gregory XIII, Sixtus V, and Clement VIII. He was one of the first scholars to recognise prehistoric stone tools as human-made rather than natural or mythologically created thunderstones.

Giordano Bruno uses Fabrizio Mordente's "proportional eight-pointed compass" to refute Aristotle's hypothesis on the incommensurability of infinitesimals, thus confirming the existence of the "minimum" which lays the basis of his own atomic theory. Bruno publishes his proofs as Figuratio Aristotelici Physici auditus.

Simon Stevin publishes De Thiende, introducing a form of decimal fraction.

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1586

Jacques Daléchamps publishes Historia generalis plantarum in Lyon, describing 2,731 plants, a record number for this time.

Galileo publishes La Billancetta, describing an accurate balance to weigh objects in air or water.

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1587

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1588

Ferdinando I de Medici, Grand Duke of Tuscany, appoints Galileo to the professorship of mathematics at the University of Pisa.

Pietro Cataldi discovers the sixth and seventh Mersenne primes by this year.

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1589

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1590

José de Acosta publishes Natural and Moral History of the Indies describing such weird creatures as iguanas.

Glass lenses are developed in the Netherlands and used for the first time in microscopes and telescopes.

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1591

Girolamo Porro produces a plan for a botanical garden at Padua, arguably expecting to assemble all the world's plants. Over the next century, well- traveled naturalists will abandon such goals as unrealistic.

image François Viète publishes In Artem Analyticien Isagoge, introducing the new algebra with innovative use of letters as parameters in equations.

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1592

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1593

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1594

The tulip bulbs planted by Carolus Clusius in the Hortus Botanicus Leiden, Holland, first flower.

Francis Bacon pens Gesta Grayorum, a staged debate related to science.

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1595

image Bartholomaeus Pitiscus publishes Trigonometria: sive de solutione triangulorum tractatus brevis et perspicuus in Heidelberg, introducing the term trigonometry to Western European languages.

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1596

image Johannes Kepler's Mysterium Cosmographicum is the first published defense of the Copernican (heliocentric) system of planetary motion. This book explains Kepler's cosmological theory, based on the Copernican system, in which the five Pythagorean regular polyhedra dictate the structure of the universe and reflect God's plan through geometry. This was the first attempt since Copernicus to say that the theory of heliocentrism is physically true.

image Abraham Ortelius, in the last edition of his Thesaurus geographicus, considers the possibility of continental drift.

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1597

image Andreas Libavius's chemistry textbook Alchemia published. Libavius was a staunch believer in chrysopoeia, or the ability to transmute a base metal into gold. This viewpoint was a matter of much debate for alchemists of the time and he defended it in several of his writings. Though he did discover several new chemical processes, he tended to be more of a theoretician and he leaned toward traditional Aristotelianism rather than Paracelsian alchemy.

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1598

image Tycho Brahe's star catalogue Astronomiae instauratae mechanica, listing the positions of 1,004 stars, is published.

Jean Bauhin, a former student of Conrad Gesner's, publishes a monograph of the medicinal waters and surrounding environment of the German fountains at Boll, the first publication of a complete set of fossils from a specific location.

image After being separated from the main Second Dutch Expedition to Indonesia fleet of Admiral Wybrand Van Warwyck, three ships under Jacob Cornelisz. van Neck land on the island which they name Mauritius and sight the dodo bird (Raphus cucullatus); it will become extinct around 1681.

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1599

image Lawyer Carlo Ruini's Anatomia del cavallo is published posthumously in Venice. This anatomy of the horse is the first published of any non-human animal.

image Ferrante Imperato publishes Dell'Historia Naturale (Natural History) attempting to catalog all of nature's animal, vegetable and mineral forms. He illustrated the book with his own cabinet of curiosities displayed at Palazzo Gravina in Naples. The engraving became the first pictorial representation of a Renaissance humanist's displayed natural history research collection.

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1600

William Gilbert, court physician to Elizabeth I, describes the Earth's magnetism in De Magnete.

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1601

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1602

Ulisse Aldrovandi publishes De Animalibus Insectis.

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1603

Prince Federico Cesi establishes the Lincean, or Lyncean, Academy in Rome, perhaps the first scientific academy of the modern era.

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1604

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1605

The German mathematician and astronomer Johannes Kepler establishes his three Laws of Planetary Motion, mathematical laws that describe the motion of planets in the Solar System, including the ground-breaking idea that the planets follow elliptical, not circular, paths around the Sun. Newton later used them to deduce his own Laws of Motion and his Law of Universal Gravitation.

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1606

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1607

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1608

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1609

image Galileo constructs the first telescope.

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1610

image The Italian mathematician and physicist Galileo Galilei develops an astronomical telescope powerful enough to indentify moons orbiting Jupiter, sunspots on the Sun and the different phases of Venus, all of which are instrumental in convincing the scientific community of the day that the heliocentric Copernican model of the Solar System is superior to the geocentric Ptolemiac model.

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1611

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1612

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1613

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1614

image Logarithms presented by John Napier in his book Mirifici Logarithmorum Canonis Descriptio (A Description of the Wonderful Law of Logarithms), which contained fifty-seven pages of explanatory matter and ninety pages of tables of numbers related to natural logarithms (see Napierian logarithm). The book also has an excellent discussion of theorems in spherical trigonometry, usually known as Napier's Rules of Circular Parts.

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1615

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1616

Fabio Colonna publishes "Dissertation on Tongue Stones" arguing that "nobody is so stupid" that he or she will not agree that tongue stones are really shark teeth. Like Rondelet several decades earlier, he attracts little attention.

Italian philosopher Lucilio Vanini suggests that humans descended from apes. In 1618 Vanini is arrested and, after a prolonged trial, condemned to have his tongue cut out, to be strangled at the stake and to have his body burned to ashes. The sentence was executed on 9 February 1619.

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1617

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1618

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1619

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1620

image English philosopher Francis Bacon publishes Novum Organum (New Instrument), which seeks to add inductive reasoning to the tools of deductive inquiry that had been outlined in Aristotle's treatises of logic known as the Organum.

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1621

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1622

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1623

image Gaspard Bauhin publishes Pinax Theatri Botanici describing some 6,000 plants.

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1624

Galileo presents to Cesi, founder of the Lincean Academy, a "little eyeglass" (a microscope). The invention will enable the Linceans to study natural objects with unprecedented precision. They will start with bees, then move on to flies and dust mites.

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1625

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1626

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1627

image Aurochs go extinct.

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1628

image William Harvey publishes Exercitatio Anatomica de Motu Cordis et Sanguinis in Animalibus (Latin for "An Anatomical Exercise on the Motion of the Heart and Blood in Living Beings"). The book established the circulation of the blood and was a landmark in the history of physiology. Just as important as its substance was its method. Harvey combined observations, experiments, measurements, and hypotheses in extraordinary fashion to arrive at his doctrine. His work is a model of its kind. It had an immediate and far-reaching influence on Harvey's contemporaries. In the book, Harvey investigated the effect of ligatures on blood flow. The book also argued that blood was pumped around the body in a "double circulation", where after being returned to the heart, it is recirculated in a closed system to the lungs and back to the heart, where it is returned to the main circulation.

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1629

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1630

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1631

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1632

image Galileo Galilei first describes the Principle of Relativity, the idea that the fundamental laws of physics are the same in all inertial frames and that, purely by observing the outcome of mechanical experiments, one cannot distinguish a state of rest from a state of constant velocity.

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1633

image Under compulsion, Galileo rejects the Copernican system.

image The French philosopher René Descartes outlines a model of a static, infinite universe made up of tiny “corpuscles” of matter, a viewpoint not dissimilar to ancient Greek atomism. Descartes’ universe shares many elements of Sir Isaac Newton’s later model, although Descartes’ vacuum of space is not empty but composed of huge swirling whirlpools of ethereal or fine matter, producing what would later be called gravitational effects.

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1634

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1635

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1636

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1637

Francesco Stelluti publishes a summary of research on fossil wood conducted by himself and fellow Lincean Academy member Federico Cesi. Though resulting from meticulous research, the work reaches the wrong conclusion, describing the origin of fossil wood as inorganic.

image Pierre de Fermat formulates his so-called Last Theorem, unsolved until 1995. In number theory, Fermat's Last Theorem (sometimes called Fermat's conjecture, especially in older texts) states that no three positive integers a, b, and c satisfy the equation an + bn = cn for any integer value of n greater than 2. The cases n = 1 and n = 2 have been known to have infinitely many solutions since antiquity. This theorem was first conjectured by Pierre de Fermat in 1637 in the margin of a copy of Arithmetica where he claimed he had a proof that was too large to fit in the margin.

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1638

image Galileo Galilei demonstrates that unequal weights would fall with the same finite speed in a vacuum, and that their time of descent is independent of their mass. Thus, freely falling bodies, heavy or light, have the same constant acceleration, due to the force of gravity.

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1639

image Jeremiah Horrox observes the first transit of Venus. Horrox (or Horrocks) was an English astronomer. He was the first person to demonstrate that the Moon moved around the Earth in an elliptical orbit; and he was the only person to predict the transit of Venus of 1639, an event which he and his friend William Crabtree were the only two people to observe and record.

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1640

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1641

Calvinist lawyer Isaac La Peyrère seeks permission to publish his manuscript claiming that people have existed before Adam, and that Chaldeans can legitimately trace their civilization back 470,000 years. Permission is denied, but he will publish Men Before Adam anonymously 14 years later, inciting both outrage and mild amusement among religious leaders.

Dutch anatomist Nicolaas Tulp produces the first formal description of an ape (a chimp, bonobo or orangutan).

René Descartes publishes Principles of Philosophy arguing that the universe is governed by simple laws and that natural processes could have shaped the Earth.

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1642

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1643

Workers dig up a skeleton in Flanders. A court physician to the Danish king observes the excavation, measures the skeleton in "Brabantian cubits," and attributes the skeleton to a giant. It will later be identified as a fossil proboscidian.

image Evangelista Torricelli invents the barometer.

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1644

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1645

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1646

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1647

image Christiaan Huygens invents the pendulum and applies its workings to create highly accurate pendulum clocks.

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1648

Franciscus Hackius publishes a lavish book on the natural history and medicines available from Brazil, Historia Naturalis Brasileae.

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1649

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1650

Irish archbishop James Ussher calculates the date of creation, based on the ages of biblical prophets. Using his calculations, theologians will identify the date of creation as on October 26, 4004 BC.

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1651

William Harvey publishes Exercitationes de generatione animalium (On Animal Generation) explaining that all animal life begins as eggs, whether in birds, amphibians or mammals. According to Joseph Needham, in this work Harvey: (1) presented a doctrine of omne vivum ex ovo (all life comes from the egg), the first definite statement against the idea of spontaneous generation; (2) denied the possibility of generation from excrement and from mud, and pointed out that even worms have eggs; (3) identified the citricula as the point in the yolk from which the embryo develops and the blastoderm surrounding the embryo; (4) destroyed once and for all the Aristotelian (semen-blood) and Epicurean (semen-semen) theories of early embryogeny; and (5) settled the long controversy about which parts of the egg were nutritive and which was formative, by demonstrating the unreality of the distinction.

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1652

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1653

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1654

image Otto von Guericke invents a vacuum pump consisting of a piston and an air gun cylinder with two-way flaps designed to pull air out of whatever vessel it was connected to, and used it to investigate the properties of the vacuum in many experiments. This pump is described in Chapters II and III of Book III of the Experimenta Nova and in the Mechanica Hydraulico-pneumatica. Guericke demonstrated the force of air pressure with dramatic experiments. In 1657, he machined two 20-inch diameter hemispheres and pumped all the air out of them, locking them together with a vacuum seal. The air pressure outside held the halves together so tightly that sixteen horses, eight harnessed to each side of the globe, could not pull the halves apart. It would have required more than 4,000 pounds of force to separate them.

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1655

Danish scholar Ole Worm publishes Musei Wormiani Historia, a successful book about his cabinet of natural curiosities.

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1656

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1657

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1658

Jesuit missionary Martino Martini publishes a manuscript explaining that documented Chinese history predates the time generally understood to mark Noah's flood (2,300 BC).

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1659

John Tradescant deeds his family treasures to fellow collector Elias Ashmole. Ashmole will later donate the collection to Oxford University, stipulating that a separate building is to be constructed for it.

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1660

Foundation of the Royal Society, London, for the promotion of mathematical and physical science.

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1661

Robert Boyle publishes The Sceptical Chymist helping to transform alchemy into chemistry. Though an alchemist himself with his own cache of secret notebooks, Boyle begins writing up experiments for use by others.

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1662

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1663

German physician Otto von Guericke pieces together bones from different species to make a fossil "unicorn."

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1664

In his private museum in Rome, Virgilio Romano exhibits a Hippopotamus major canine tooth found in Pleistocene gravels along the Via Nomentana.

Thomas Willis publishes The Anatomy of the Brain and Nerves.

image Isaac Newton discovers that white light is composed of different colors.

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1665

image Robert Hooke observes cork under a microscope and uses the word cells to describe the tiny chambers that he sees. He publishes drawings of these cells, of fleas, and of other small creatures, in his book Micrographia.

Le Journal des Savants is first published in France, and Philosophical Transactions of the Royal Society is first published in England.

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1666

Gravity is discovered.

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1667

Niels Stensen (Steno) describes his dissection of the head of a giant white shark and correctly identifies shark teeth, still generally thought (despite arguments to the contrary from Rondelet and Colonna in the preceding century) to be serpent tongues.

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1668

Natural historian John Somner finds woolly rhino teeth near Canterbury in Kent, and figures they might be the remains of a sea monster. As he will die before he can publish his conclusions, his brother William will print his article A Brief Relation of Some Strange Bones There Lately Digged Up In Some Grounds of Mr. John Somner.

image Francesco Redi publishes Esperienze Intorno alla Generazione degli Insetti (Experiments on the Generation of Insects), which is regarded as his masterpiece and a milestone in the history of modern science. At the time, prevailing wisdom was that maggots arose spontaneously from rotting meat. Redi took six jars and divided them into two groups of three: In one experiment, in the first jar of each group, he put an unknown object; in the second, a dead fish; in the last, a raw chunk of veal. Redi covered the tops of the first group of jars with fine gauze so that only air could get into it. He left the other group open. After several days, he saw maggots appear on the objects in the open jars, on which flies had been able to land, but not in the gauze-covered jars. In the second experiment, meat was kept in three jars. One of the jars was uncovered, and two of the jars were covered, one with cork and the other one with gauze. Flies could only enter the uncovered jar, and in this, maggots appeared. In the jar that was covered with gauze, maggots appeared on the gauze but did not survive. Knowing full well the terrible fates of out-spoken thinkers such as Giordano Bruno and Galileo Galilei, Redi was careful to express his new views in a manner that would not contradict theological tradition of the Church; hence, his interpretations were always based on biblical passages, such as his famous adage: omne vivum ex vivo ("All life comes from life").

Jan Swammerdam dissects a caterpillar for Cosimo de Medici, demonstrating that the butterfly wings already exist inside the caterpillar's body. A year later, he will publish Historia Insectorum Generalis.

Robert Hooke presents a lecture to the Royal Society claiming that earthquakes, not the biblical flood, have caused fossils to be found on mountaintops and buried in stone.

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1669

Niels Stensen (Steno) publishes Forerunner, showing diagrammatic sections of the Tuscany area geology, making the important point that sediments are deposited in horizontal layers.

Brandt discovers phosphorus.

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1670

Agostino Scilla publishes Vain Speculation Undeceived by Sense arguing for the organic origin of fossils.

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1671

The Greenwich Observatory is built.

image Isaac Newton completes his book, The Methods of Fluxions and Infinite Series, with its Application to the Geometry of Curve-lines (which was not published until 1736). The book describes Newton's analytic methods, which would now be called calculus.

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1672

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1673

image Apothecary and antiquary John Conyers finds an elephant tusk and a nearby handaxe about 12 feet below ground at Gray's Inn Lane, London. The Gray's Inn Lane handaxe will later be dated at 350,000 years old.

Leeuwenhoek begins corresponding with the Royal Society of London describing his discoveries under the microscope.

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1674

image Antonie van Leeuwenhoek creates a simple microscope with only one lens. He developed glass-handling techniques that allowed him to create lenses with magnifying power up to 270x — by far the most powerful magnifying lenses available. Although compound microscopes had been invented in the 1590s, nearly forty years before Leeuwenhoek was born, there were technical difficulties in building them, meaning that early compound microscopes (such as used by Robert Hooke) had a maximum magnification of only 20x or 30x. Leeuwenhoek's more powerful lenses allowed him to discover protozoa and other single-celled organisms and to be the first to observe bacteria.

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1675

Jan Swammerdam publishes a treatise on the mayfly entitled A Figure of Man's Miserable Life.

The English physicist Sir Isaac Newton argues that light is composed of particles, which are refracted by acceleration toward a denser medium, and posits the existence of “aether” to transmit forces between the particles.

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1676

image The first quantitative estimate of the speed of light was made in 1676 by Danish astronomer Ole Rømer. From the observation that the periods of Jupiter's innermost moon Io appeared to be shorter when the Earth was approaching Jupiter than when receding from it, he concluded that light travels at a finite speed, and estimated that it takes light 22 minutes to cross the diameter of Earth's orbit. Christiaan Huygens combined this estimate with an estimate for the diameter of the Earth's orbit to obtain an estimate of speed of light of 220000 km/s, 26% lower than the actual value.

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1677

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1678

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1679

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1680

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1681

Royal Society member Neremiah Grew examines the "sea serpent teeth" found by John Somner in 1668 and recognizes that they are rhino teeth.

Amsterdam physician Gerard Blasius publishes Anatome Animalium examining animals' internal anatomy and skeletal structure.

The first museum of natural history is established in London.

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1682

Neremiah Grew publishes The Anatomy of Plants with microscopic observations of plant features.

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1683

Oxford opens the Ashmolean Museum, the world's first public museum. The museum's practice of allowing entry to anyone who pays the admission fee horrifies scholars from continental Europe.

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1684

Dublin doctor Thomas Molyneux shows that a "giant's tooth" from the collection of Ole Worm really belongs to a whale, and a "giant's hand" shown in London is really the fin of a porpoise.

image Filippo Buonanni publishes Ricreatione dell' occhio e della mente. — perhaps the first book devoted entirely to shells, for which he is considered a founder of conchology.

image Gottfried Wilhelm von Leibniz publishes a description of his invention of the differential calculus.

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1685

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1686

Timothy Nourse anticaptes eugenics with the argument that a gentleman "ought at least to be as careful of his race as he is of that of his horses, where the fairest and most beautiful are made choice of for breed."

Robert Boyle composes Free Inquiry into the Vulgarly Received Notion of Nature criticizing the notion that nature is capable of autonomy from God.

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1687

image Sir Isaac Newton publishes his Philosophiæ Naturalis Principia Mathematica (or just Principia), which describes an infinite, steady state, static, universe, in which matter on the large scale is uniformly distributed. In the work, he establishes the three Laws of Motion (“a body persists its state of rest or of uniform motion unless acted upon by an external unbalanced force”; “force equals mass times acceleration”; and “to every action there is an equal and opposite reaction”) and the Law of Universal Gravitation (that every particle in the universe attracts every other particle according to an inverse-square formula) that were not to be improved upon for more than two hundred years. He is credited with introducing the idea that the motion of objects in the heavens (such as planets, the Sun and the Moon) can be described by the same set of physical laws as the motion of objects on the ground (like cannon balls and falling apples).

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1688

Giovanni Ciampini describes remains of the extinct straight-tusked elephant, Elephas antiquus, found in the town of Vitorchiano in the region of Latium.

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1689

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1690

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1691

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1692

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1693

Naturalist John Ray publishes Three Physicotheological Discourses about the Creation, the Deluge and the Conflagration, discussing conflicting theories about the nature of fossils.

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1694

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1695

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1696

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1697

Scandinavian historian Olof Rudbeck publishes his attempt to chronologically measure sedimentary deposits, laying the foundations for the field of stratigraphy.

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1698

Edward Lhwyd publishes a description of a "flatfish" in the Philosophical Transactions of the Royal Society. (The flatfish is really a trilobite, an ancient marine arthropod.)

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1699

Edward Lhwyd publishes a book devoted to British fossils. In it, he describes ichthyosaur remains as those of a fish.

Based on a dissection he performed the year before, Edward Tyson publishes Orang Outan, sive Homo sylvestris pointing out similarities between chimpanzee and human anatomy. (Although he has dissected an infant chimp, Tyson uses the term "orang-outan.")

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1700

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1701

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1702

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1703

image Isaac Newton is elected president of the Royal Society.

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1704

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1705

A giant fossil tooth is found along the banks of the Hudson River. It will initially be identified (by Cotton Mather) as that of a human giant who perished in Noah's flood, then correctly identified (by Georges Cuvier) as that of a mastodon.

Maria Sibylla Merian publishes Metamorphosis Insectorum Surinamensium describing insect species and other animals she has studied in Surinam.

The Ambonese Curiosity Cabinet by G.E. Rumphius is published. It provides detailed descriptions of soft and hard shellfish, minerals, rocks and fossils from Indonesia.

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1706

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1707

Hans Sloane publishes the first of two volumes describing the natural wonders of Jamaica. (The second volume will be published in 1725.)

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1708

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1709

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1710

image George Berkeley publishes "A Treatise Concerning the Principles of Human Knowledge."

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1711

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1712

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1713

In Physico-theology, or a demonstration of the being and attributes of God from His works of creation William Derham tries to show that this is the best of all possible worlds.

(no entry for this year)

1714

On the advice of Leibniz, Peter the Great opens a public museum in Saint Petersburg.

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1715

Edmund Halley lectures the Royal Society that the age of the Earth could be calculated by measuring the ocean's salinity since ocean salts result from sediments carried by rivers and streams.

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1716

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1717

William Stukely publishes An Account of the Almost Entire Sceleton of a Large Animal in a Very Hard Stone. The fossil is a plesiosaur, but is identified as a crocodile.

Dutch pharmacist Albertus Seba inventories his wonder cabinet for the avid collector Peter the Great, including 1,000 European insects and 400 animal specimens. The czar buys the inventory, and Seba begins his second collection, which he will describe in print starting in 1734.

(no entry for this year)

1718

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1719

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1720

René Réaumur submits a report to the Paris Academy of Sciences proposing that a brief Noachian flood cannot account for the thick sedimentary layers (composed largely of broken shells) underlying the region of Tours. He suggests instead that the region was once covered by the sea.

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1721

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1722

Benoît de Maillet anonymously publishes Telliamed, named after an oriental sage who says that the Earth must be at least 2 billion years old, based on measurements of falling sea level. (In fact, no sage exists; the title is really the author's name spelled backward.)

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1723

Antoine de Jussieu addresses a paper to the Académie des Sciences suggesting that an ancient object, e.g., a stone tool, made of the same material and by the same process as those used by a modern population probably has the same function.

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1724

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1725

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1726

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1727

Balthasar Ehrhart identifies belemnites as fossil cephalopods.

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1728

Hans Sloane publishes two papers on fossils found in Siberia and North America arguing that they are fossil elephants, not giants or monsters.

(no entry for this year)

1729

In An Attempt towards a Natural History of England, John Woodward describes three "pinecones" that, upon later examination, will prove to be coprolites.

Louis Bourget's Lettres philosophiques sur la formation des sels et de cristaux et sur la génération et la méchanique organique (Philosophical letters on the formation of salts and crystals and on generation and organic mechanisms) makes the distinction between organic and inorganic growth.

(no entry for this year)

1730

Otto Müller is among the first to see bacteria since Leeuwenhoek and the first to classify them into types.

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1731

image Jethro Tull's Horse-hoeing husbandry advocates the use of manure, pulverization of the soil, growing crops in rows, and hoeing to remove weeds.

Johann Jakob Scheuchzer publishes Sacred Physics, a pictorial account of Earth's history based on the Old Testament. Included is a description of what he believes is a fossilized victim of the biblical flood.

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1732

image Nöel-Antoine Pluche publishes the first of eight volumes of Le spectacle de la nature (Spectacle of nature), popularizing "natural theology" in France.

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1733

image Stephen Hales' Statical essays, containing haemastatics, etc., two volumes, reports his investigations on blood flow and pressure in animals and the hydrostatics of sap in plants.

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1734

The Swedish scientist and philosopher Emanuel Swedenborg proposes a hierarchical universe, still generally based on a Newtonian static universe, but with matter clustered on ever larger scales of hierarchy, endlessly being recycled. This idea of a hierarchical universe and the “nebular hypothesis” were developed further (independently) by Thomas Wright (1750) and Immanuel Kant (1775).

image René de Réamure's Mémaoires pour servir à l'histoire des insects (History of insects) is one of the foundation works in entomology.

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1735

image Systema Naturae (System of Nature) by Carolus Linnaeus introduces the system of classification for organisms that is still in use today.

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1736

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1737

Hermann Boerhaave prints Jan Swammerdam's Biblia naturae (Bible of nature), which was originally published to little notice in 1658. It contains his reports on the dissection of insects under a microscope.

image Linnaeus's Genera Plantorum (Genera of Plants) explains his method of systematic botany and classifies 18,000 species of plants.

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1738

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1739

Native Americans traveling with French soldiers find mastodon fossils along the Ohio River. The bones will be shipped back to France and become the first American fossils studied by scientists.

image David Hume publishes A Treatise of Human Nature.

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1740

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1741

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1742

Abraham Trembley makes the first permanent graft of animal tissue, using the Hydra.

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1743

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1744

Abraham Trembley's Mémoires summarizes his research on the hydra and his discovery of regeneration in polyps.

Scholar and teacher Abraham Trembley publishes Mémoires Concerning the Natural History of a Type of Freshwater Polyp with Arms Shaped Like Horns. After watching them move and eat, he has concluded that the simple creatures (later to be classified as cnidarians) are animals, not plants.

(no entry for this year)

1745

image Traité d'insectologie (Treatise on insect ecology) by Charles Bonnet describes his observations on parthenogenetic reproduction and metamorphosis of aphids.

Bologna physician Vincenzo Menghini roasts the blood of fish, birds and mammals (including humans) then sifts through the residue with a magnetic blade, noting that roasted-blood particles adhere to it. The experiment provides evidence that blood contains iron.

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1746

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1747

image Andreas Marggraf discovers sugar in beets, laying the foundation for Europe's sugar-beet industry.

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1748

image L'homme Machine (Man the Machine) by Julien Offray de la Mettrie describes humans as machines, without freedom or will.

(no entry for this year)

1749

image Georges-Louis Leclerc de Buffon publishes the first volume of Historie Naturelle. Thirty-six volumes came out between 1749 and 1789, followed by eight more after his death. The Histoire Naturelle was meant to address the whole of natural history, but actually covers only minerals, birds, and the quadrupeds among animals. It is accompanied by some discourses and a theory of the earth by way of introduction, and by supplements including an elegantly written account of the epochs of nature. The Histoire Naturelle had a distinctly mixed reception in the eighteenth century. Wealthy homes in both England and France purchased copies, and the first edition was sold out within six weeks. But Buffon was criticised by some priests for suggesting (in the essay Les Epoques de Nature, Volume XXXIV) that the earth was more than 6,000 years old and that mountains had arisen in geological time. The Paris faculty of theology, acting as the official censor, wrote to Buffon with a list of statements in the Histoire Naturelle that were contradictory to Roman Catholic Church teaching. In June, 2017, an antiquarian book deal offered a complete second edition of the Historie Naturelle for 14500 €.

image Carolus Linnaeus's Philosophia Botanica rejects any notion of evolution and continues his work in classifying plants.

1750

image Carolus Linnaeus's Philosophia Botanica rejects any notion of evolution and continues his work in classifying plants.

John Needham publishes Nouvelles Observations Microscopiques arguing that decomposing plant and animal matter can spontaneously generate new life. Fifteen years later, Italian polymath Lazzaro Spallanzani will conduct a more careful set of experiments then publish a report rejecting Needham's conclusions.

image Linnaeus's Species Plantarum completes his development of the use of binary nomenclature in botany. The work still provides the foundation for the modern classification of species.

image Pierre-Louis de Maupertuis's Système de la Nature provides a theoretical speculation on heredity and the origin of species by chance.

1751

image Linnaeus's Species Plantarum completes his development of the use of binary nomenclature in botany. The work still provides the foundation for the modern classification of species.

image Pierre-Louis de Maupertuis's Système de la Nature provides a theoretical speculation on heredity and the origin of species by chance.

image Étienne Bonnot de Condillac's Traité de sensations claims that knowledge reaches humans only through the senses.

image Benjamin Franklin describes electricity as a single fluid and distinguishes between positive and negative electricity in Experiments and Observations on Electricity. He shows that electricity can magnetize and demagnetize iron needles.

Encyclopedists Diderot and d'Alembert publish the first volume of the Encyclopedia, or Classified Dictionary of Sciences, Arts and Trades emphasizing a dispassionate presentation of factual information rather than reliance on age-old "wisdom."

(no entry for this year)

1752

image The lightning conductor is invented by Benjamin Franklin, whose experiments with lightning include a flying a kite in a thunderstorm. The kite experiment shows that lightning is a form of electricity, similar to the discharge from a Leyden jar.

Stung by satires of its Philosophical Transactions, the Royal Society of London forms a committee that will vote on which papers merit publication.

(no entry for this year)

1753

image Russian scientist Georg Wilhelm Richmann is killed performing a lightning experiment in St. Petersburg. Richmann is electrocuted in while trying to quantify the response of an insulated rod to a nearby storm. The incident, reported worldwide, underscored the dangers inherent in experimenting with insulated rods and in using protective rods with faulty ground connections.

The British Museum opens.

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1754

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1755

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1756

image William Cullen observes the cooling effect of evaporating liquids and publishes the results in An Essay on the Cold Produced by Evaporating Fluids and Other Means of Producing Cold.

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1757

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1758

Henri-Louis Duhamel du Monceau discovers that when he turns a seedling upside down, its roots and shoots reorient so that the root continues to grow downward while the shoot continues to grow upward.

(no entry for this year)

1759

image In Theoria Generationis (his MD dissertation), Caspar Friedrich Wolff claims the existence of a vis essentialis — an essential force — that is at the heart of all living matter. He also describes the differentiation of tissues in a developing embryo, refuting the preformation concept — the idea that development consists in the growth of a fully formed, but miniature individual. His views were not well received.

The Kew Botanical Gardens open in London.

image Joseph Gottlieb Kölreuter'S Vorläufige nachricht von einigen das geschlecht der pflantzen betreffende versuche and beobachtungen describes his research in heredity in plants.

1760

image Joseph Gottlieb Kölreuter'S Vorläufige nachricht von einigen das geschlecht der pflantzen betreffende versuche and beobachtungen describes his research in heredity in plants.

Giovanni Arduino proposes a naming system for geologic strata, in order of oldest to youngest: Primary: lacking fossils; Secondary: tilted with fossils; Tertiary: horizontal with fossils; Quaternary: sands and gravels overlying Tertiary strata. Although he does not relate these systems to scripture, many people will interpret them in terms of biblical events.

image Photometria by German physicist Johann Lambert is an investigation of light reflections from planets, introducing the term ALBEDO (whiteness) for the differing reflectivities of planetary bodies.

image In experiments with primitive apparatus, Daniel Bernoulli decides that the electrical force obeys an inverse square law similar to that of gravity.

Jean-Baptiste Robinet's five-volume De la nature claims that organic species form a linear scale of progress, without gaps.

image Between 1761 and 1766, Joseph Gottlieb Kölreuter (Germany) demonstrates that hybrid offspring receive traits from both parents (pollen and ovule transmit genetic information), and are intermediate in most traits. First scientific hybrid produced (tobacco). Demonstrates the identity of reciprocal crosses. Notes hybrid vigor, segregation of offspring (parental and non-parental types) from a hybrid.

1761

The Swiss physicist Johann Heinrich Lambert supports Wright and Kant’s hierarchical universe and nebular hypothesis, and also hypothesizes that the stars near the Sun are part of a group which travel together through the Milky Way, and that there are many such groupings or star systems throughout the galaxy.

Jean-Baptiste Robinet's five-volume De la nature claims that organic species form a linear scale of progress, without gaps.

image Between 1761 and 1766, Joseph Gottlieb Kölreuter (Germany) demonstrates that hybrid offspring receive traits from both parents (pollen and ovule transmit genetic information), and are intermediate in most traits. First scientific hybrid produced (tobacco). Demonstrates the identity of reciprocal crosses. Notes hybrid vigor, segregation of offspring (parental and non-parental types) from a hybrid.

image Joseph Black discovers latent heat by finding that ice, when melting, absorbs heat without changing in temperature. Later he measures the latent heat of steam — that is, the heat required to keep water boiling without raising its temperature.

image Charles Bonnet's Considerations sur les corps organisées gives his theory of "preformation" — the idea that each creature is already preformed in miniature in the egg, and that the egg contains all future generations in even smaller scale, ad infinitum.

1762

image Charles Bonnet's Considerations sur les corps organisées gives his theory of "preformation" — the idea that each creature is already preformed in miniature in the egg, and that the egg contains all future generations in even smaller scale, ad infinitum.

George III purchases the Paper Museum of Cassiano Dal Pozzo, a 17th- century patron of arts and sciences. Preserved by the Albani family, this "museum" contains more than 7,000 science illustrations, including highly accurate depictions from the Lincean Academy that will prove invaluable to later science historians.

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1763

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1764

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1765

image Italian biologist Lazzaro Spallanzani suggests preserving food by sealing it in containers that do not permit air to penetrate.

image Leonhard Euler gives a general treatment of the motion of rigid bodies, including the precession and nutation of earth, in Theoria motus corporum solidorum seu rigidorum (Theory of the motion of solid and rigid bodies).

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1766

image Albrecht von Haller is the first to show that nerves stimulate muscles to contract and that all nerves lead to the spinal cord and the brain.

image Horace-Bénédict de Saussure invents the electrometer, a device for measuring the electric potential by means of the attraction or repulsion of charged bodies.

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1767

Benjamin Franklin writes a thank-you letter to a wealthy Irish trader for a box of proboscidian "tusks and grinders." Franklin believes the remains belong to elephants but makes astute observations about how their climate must have differed from the present.

(no entry for this year)

1768

image Lazzaro Spallanzani's Prodromo d'un ouvrage sur les reproductions animales (Foreword to a work on animal reproduction) tells of his demonstration that spontaneous generation of animals does not take place in tightly closed bottles that have been boiled for more than 30 minutes.

image Caspar Friedrich Wolff's De formatione intestinarum establishes principles of the formation of organs in embryos.

James Cook sets sail on the Endeavour bound for the South Pacific. Accompanying Cook is naturalist Joseph Banks, who will collect tens of thousands of plant and animal specimens and initiate the exchange of flora and fauna between Europe, the Americas and the South Seas.

image Charles Bonnet's Philosophical palingenesis, or ideas on the past and future states of living beings contains his view that the females of every species contain the germs of all future generations.

1769

image Charles Bonnet's Philosophical palingenesis, or ideas on the past and future states of living beings contains his view that the females of every species contain the germs of all future generations.

image John Robison measures the repulsion between two charged bodies and shows that this force is inversely proportional to the distance between the two bodies.

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1770

Erasmus Darwin has the allegorical motto E conchis omnia or "Everything from shells" painted on his carriage, promoting the idea of common descent. Bowing to social pressure, he removes it shortly thereafter.

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1771

In Gailenreuth Cave in Germany, Father Johann Esper finds human bones underlying those of extinct animals. He concludes that the bones got there by accident, an opinion Cuvier will share.

image Italian anatomist Luigi Galvani discovers accidentally the action of electricity on the muscles of the dissected frog: it causes a twitch.

Joseph Priestly discovers that a plant can produce enough breathable air to sustain a mouse and keep a candle burning. Though he describes it in different terms, he has discovered oxygen.

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1772

New Jersey passes bill requiring a license to practice medicine.

Swedish scientist Johan Carl Wilcke calculates the latent heat of ice (the amount of heat absorbed when ice turns into water).

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1773

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1774

image Joseph Priestley discovers oxygen.

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1775

image Franz Anton Mesmer suggests that "animal magnetism" causes attractions between certain persons. Mesmer's name becomes the root of the English verb "mesmerize".

image Johann Christian Fabricius's Systema Entomologiae classifies insects based on the structure of mouth organs rather than wings.

image Alessandro Volta describes his electrofore perpetuo device for producing and storing a charge of static electricity. This device replaces the Leyden jar and eventually leads to modern electrical condensers.

image Grand duke Pietro Leopoldo establishes the Royal Museum of Physics and Natural History (La Specola) in Florence. Unlike many older natural history repositories, this institution will admit any visitor, at least anyone meeting the museum's standards for dress and hygiene. The museum includes a stuffed hippopotamus, that once belonged to Cosimo III, a member of the Medici who had a penchant for exotic animals. The hippo once roamed the Boboli Gardens. After its death, the hippo was inexpertly stuffed, and later displayed in Florence’s Museum of Zoology and Natural History (La Specola), where it can still be seen today.

(no entry for this year)

1776

Abbé Jacques-François Dicquemare describes reptilian fossils in Journal de Physique but refrains from speculating about their sources.

image Pierre-Simon Laplace states that if all of the forces on all objects in any one time are known, then the future can be completely predicted.

(no entry for this year)

1777

image Charles-Augustin Coulomb invents the torsion balance.

(no entry for this year)

1778

Buffon publishes Les Epoques de la Nature, asserting that the Earth is a staggering 74,832 years old, and has existed long before the arrival of humans or any other form of life.

The peculiar inheritance of human color-blindness reported to The Royal Society of London by Michael Lort.

1779

image Jan Ingenhousz discovers two distinct respiratory cycles in plants: at night oxygen is absorbed and carbon dioxide is exhaled; during the day carbon dioxide is absorbed and oxygen is exhaled. The exact nature of the exhaled gases becomes clear with the later discoveries by Lavoisier.

Jan Ingenhousz discovers photosynthesis: In Experiments on Vegetables Ingenhousz shows that sunlight is essential for the production of oxygen by leaves.

The peculiar inheritance of human color-blindness reported to The Royal Society of London by Michael Lort.

image Lazzaro Spallanzani studies the role of semen in fertilization and learns that the sperm must make physical contact with the egg for fertilization to take place.

(no entry for this year)

1780

image William Herschel discovers first binary star, Xi Ursae Majoris.

Abraham Gottlob Werner asserts that all rocks have been deposited by a primordial ocean. This "Neptunian" view is accepted with little question.

(no entry for this year)

1781

image Pierre François André Méchain discovers M80 (globular cluster in Scorpio).

image Coloumb's Théorie des machiones simple (Theory of simple machines) is a study of friction.

Johan Carl Wilcke introduces the concept of SPECIFIC HEAT.

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1782

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1783

The amateur British astronomer John Michell proposes the theoretical idea of an object massive enough that its gravity would prevent even light from escaping (which has since become known as a black hole). He realizes that such an object would not be directly visible, but could be identified by the motions of a companion star if it was part of a binary system. A similar idea was independently proposed by the Frenchman Pierre-Simon Laplace in 1795.

image Horace-Bénédict de Saussure's Essais sur l'hygromé (Essay on measuring humidity) describes how to construct a hygrometer from human hair that can measure relative humidity.

(no entry for this year)

1784

Historian and naturalist Cosimo Alessandro Collini publishes a description of the first known pterosaur.

George Atwood accurately determines the acceleration of a free-falling body.

Charles Willson Peale establishes a natural history museum in Philadelphia, one of the first successful American museums.

(no entry for this year)

1785

image Lazzaro Spallanzani performs artificial insemination on a dog.

image In his Theory of the Earth, James Hutton explains the principle of uniformitarianism: all geological features can be explained by changes that can be observed now, taking place over very long periods of time.

image Couloumb makes precise measurements of the forces of attraction and repulsion between charged bodies and between magnetic poles, using a torsion balance, demonstrating conclusively that electric charge and magnetism obey inverse-square laws like that of gravity. He also discovers that electrically charged bodies discharge spontaneously. In the 20th century, it is found that cosmic radiation is responsible for this discharge.

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1786

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1787

image Herschel discovers Enceladus, a moon of Saturn, and Titania and Oberon, moons of Uranus.

image Jacques-Alexandre Charles shows that different gases expand by the same amount for a given rise in temperature (Charles Law).

Thomas Jefferson publishes Notes on the State of Virginia refuting Buffon's claim that America's harsh, moist climate stunts the growth of its inhabitants. He also addresses the issue of race, describing Native Americans favorably, but African slaves unfavorably.

(no entry for this year)

1788

Juan-Bautista Bru mounts the first relatively accurate fossil reconstruction of an extinct animal from South America. Georges Cuvier classifies it as a giant sloth.

image Johann Wolfgang Goethe's Versuch, die Metamorphose der Pflanzen zu erklären (Attempt to explain the metamorphosis of plants) claims incorrectly that all plant structures are modified leaves, but clearly espouses evolution.

1789

image Gilbert White's The Natural History and Antiquities of Selborne, a series of notes about animal and plant life in Selborne, England, is the first recognizable work of ecology. It goes through about 300 different editions and is still in print today.

image Johann Wolfgang Goethe's Versuch, die Metamorphose der Pflanzen zu erklären (Attempt to explain the metamorphosis of plants) claims incorrectly that all plant structures are modified leaves, but clearly espouses evolution.

French polymath Antoine Lavoisier publishes a paper on French geology defining peacefully deposited pelagic sediments and violently deposited littoral sediments. He argues that these sediments illustrate a fluctuating sea level on an ancient planet.

The French chemist Antoine-Laurent de Lavoisier definitively states the Law of Conservation of Mass (although others had previously expressed similar ideas, including the ancient Greek Epicurus, the medieval Persian Nasir al-Din al-Tusi and the 18th Century scientists Mikhail Lomonosov, Joseph Black, Henry Cavendish and Jean Rey), and identifies (albeit slightly incorrectly) 23 elements which he claims can not be broken down into simpler substances.

(no entry for this year)

1790

German poet Johann Wolfgang von Goethe writes The Morphology of Plants stating that all plant organs, flowers included, began as leaves — an assertion that will enjoy some support from 21st-century genetic research.

(no entry for this year)

1791

image Luigi Galvani announces that electricity applied to severed frog's legs causes them to twitch and that frogs legs twitch in the presence of two different metals with no electric current present. The latter discovery eventually leads to Alessandro Volta's developing the electric battery.

image Pierre Prévost develops his theory of exchanges of radiation of heat. He correctly shows that cold is merely the absence of heat and that all bodies continually radiate heat. If they seem not to radiate heat, it means that they are in heat equilibrium with their environment.

(no entry for this year)

1792

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1793

Reverend James Douglas publishes Nenia Britannica; or, A Sepulchral History of Great Britain providing perhaps the first record of a fossil (sea urchin) at an archaeological site.

image Erasmus Darwin (Charles' grandfather) publishes Zoonomia, or the Laws of Organic Life.

James Hutton publishes An Investigation of the Principles of Knowledge. Buried in the 2,138-page philosophical tome is a chapter about variety in nature in which Hutton anticipates Charles Darwin's theory of natural selection.

image John Dalton's Extraordinary facts relating to the vision of colors gives an early account of red-green color blindness, which he refers to as Daltonism, since he is afflicted with the condition.

1794

John Frere describes and illustrates handaxes from Hoxne that will turn out to be some 400,000 years old.

image Erasmus Darwin (Charles' grandfather) publishes Zoonomia, or the Laws of Organic Life.

James Hutton publishes An Investigation of the Principles of Knowledge. Buried in the 2,138-page philosophical tome is a chapter about variety in nature in which Hutton anticipates Charles Darwin's theory of natural selection.

image John Dalton's Extraordinary facts relating to the vision of colors gives an early account of red-green color blindness, which he refers to as Daltonism, since he is afflicted with the condition.

image Zoonomia, or the Laws of Organic Life by Erasmus Darwin (grandfather of Charles Darwin) contains his ideas about evolution, which are Lamarckian in that they assume the environment has a direct influence on organisms, causing permanent changes in the germ line.

image Alessandro Volta demonstrates that the electric force observed by Galvani is not connected with living creatures, but can be obtained whenever two different metals are placed in a conducting fluid.

image James Hutton's Theory of the Earth published, interpreting certain geological strata as former sea beds. Hutton proposes geological theory of gradualism.

1795

image James Hutton's Theory of the Earth published, interpreting certain geological strata as former sea beds. Hutton proposes geological theory of gradualism.

Johann Friedrich Blumenbach publishes De generis humani varietate nativa liber arguing that humans comprise a single species with five varieties: Caucasian, Mongolian, Ethiopian, (American) Indian and Malayan.

James Hutton overturns the "Neptunian" view of rock formation in his Theory of the Earth, suggesting instead that forces of rock creation are balanced by forces of rock destruction.

(no entry for this year)

1796

(no entry for this year)

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1797

(no entry for this year)

image Publication of Thomas Malthus' Essay on the Principle of Population, a work that Darwin asserted helped him frame the principle of evolution by natural selection.

1798

image Publication of Thomas Malthus' Essay on the Principle of Population, a work that Darwin asserted helped him frame the principle of evolution by natural selection.

Henry Cavendish determines the mass of Earth by measuring the gravity between two small masses and two large masses. This gives the gravitational constant G, which was the only unknown in Newton's equations. Solving for G enables Cavendish to establish that Earth is about 5.5 times as dense as water.

image Enquiry concerning the source of heat which is excited by friction by Count Rumford (Benjamin Thompson) describes his experiments with boring cannons that show that the caloric theory of heat cannot be true, and that heat should be considered a kind of motion.

image The first mammoth fossil fully documented by modern science is discovered near the delta of the Lena River in 1799 by Ossip Schumachov, a Siberian hunter. Schumachov allows it to thaw (a process taking several years) until he can retrieve the tusks for sale to the ivory trade in Yakutsk. He then abandons the specimen, allowing it to decay before its recovery. In 1806, Russian botanist Mikhail Adams rescues what remained of the specimen and brought it to the Zoological Museum of the Zoological Institute of the Russian Academy of Sciences in St. Petersburg. The specimen, which became known as the Adams Mammoth, is stuffed and mounted, and continues to be on display at the Zoological Institute.

Charles White publishes An Account of the Regular Gradation in Man, and in Different Animals and Vegetables, a treatise on the great chain of being, showing people of color at the bottom of the human chain.

1799

image The first mammoth fossil fully documented by modern science is discovered near the delta of the Lena River in 1799 by Ossip Schumachov, a Siberian hunter. Schumachov allows it to thaw (a process taking several years) until he can retrieve the tusks for sale to the ivory trade in Yakutsk. He then abandons the specimen, allowing it to decay before its recovery. In 1806, Russian botanist Mikhail Adams rescues what remained of the specimen and brought it to the Zoological Museum of the Zoological Institute of the Russian Academy of Sciences in St. Petersburg. The specimen, which became known as the Adams Mammoth, is stuffed and mounted, and continues to be on display at the Zoological Institute.

Charles White publishes An Account of the Regular Gradation in Man, and in Different Animals and Vegetables, a treatise on the great chain of being, showing people of color at the bottom of the human chain.

Faujas publishes a description of the Maastricht animal, a spectacular mosasaur found in chalk quarries in the Netherlands, describing it as a crocodile.

Thomas Jefferson publishes a paper describing Megalonyx, a North American fossil ground sloth similar to the one found in South America.

George Shaw publishes a description of a platypus even though he suspects the odd animal might be a hoax.

Alexander von Humboldt names the Jurassic System, after the Jura Mountains. This time period will later be identified as the "middle period" for the dinosaurs.

William Smith maps rock formations in the vicinity of Bath, England, making perhaps the world's first geologic map. The same year, Smith, Joseph Townsend and Benjamin Richardson recognize rocks containing the Permian and Triassic, though not necessarily by those names. (These periods will later be identified as spanning the Earth's most catastrophic mass extinction.)

The British government purchases the collection of Scottish anatomist John Hunter, forming the Hunterian Museum.

(no entry for this year)

1800

image Between 1800 and 1803, naturalist Alexander von Humboldt visits Mexico and writes influential accounts of his observations.

image Karl Friedrich Burdach coins the term BIOLOGY to denote the study of human morphology, physiology and psychology.

Erasmus Darwin publishes Phytologia declaring that leaves breathe air through tiny pores, sugar and starch are the products of plant "digestion," and nitrates and phosphorus promote vegetation.

image Alessandro Volta announces his invention, made in 1799, of the electric battery, also known as the Voltaic pile. It consists of a stack of alternating zinc and silver discs separated by felt soaked in brine. It is the first source of a steady electric current.

image William Herschel's "An investigation of the powers of prismatic colors to heat and illuminate objects" tells of his discovery of infrared radiation. While investigating the power of different parts of the spectrum to heat a thermometer, he finds that invisible light beyond the red produces the most heat.

image Jean-Baptiste Lamarck's Système de Animaux sans Vertèbres (System for Animals without Vertebrae) includes a classification system for invertebrates and a preliminary view of his ideas of evolution.

1801

image Giuseppe Piazzi discovers first asteroid, which is later named Ceres.

image Jean-Baptiste Lamarck's Système de Animaux sans Vertèbres (System for Animals without Vertebrae) includes a classification system for invertebrates and a preliminary view of his ideas of evolution.

image The English scientist Thomas Young demonstrates, in his famous double-slit experiment, the interference of light and concludes that light is a wave, not a particle as Sir Isaac Newton had ruled.

In Natural Theology, William Paley uses the analogy of a watch requiring a watchmaker to argue that the universe implies an intelligent designer.

1802

In Natural Theology, William Paley uses the analogy of a watch requiring a watchmaker to argue that the universe implies an intelligent designer.

image image Gottfried Treviranus and Jean Baptiste de Lamarck independently broaden the meaning of BIOLOGY to include the study of all living things.

image Considered the father of modern scientific education in America, Benjamin Silliman, Sr., teaches the first modern science course (chemistry at Yale) in the United States. Silliman later becomes a founder in 1818 of the American Journal of Science, one of the oldest scientific journals in the world.

image Thomas Young's On the theory of light and colors is the first of three pivotal papers describing his wave theory of light.

(no entry for this year)

1803

(no entry for this year)

(no entry for this year)

1804

Georges Cuvier suggests that fossils found in the area around Paris are "thousands of centuries" old. This casual observation pushes the age of the Earth well beyond its commonly accepted limits. Cuvier also publishes a paper explaining that the fossil animals he has studied bear no resemblance to anything still living, an unambiguous endorsement of the theory of extinction.

James Parkinson publishes the first of a three-volume work entitled Organic Remains of a Former World. In this volume, he describes fossils as the remains of Noah's Flood. In the next several years, he will recognize fossils as the remains of a world before people, and acknowledge as much in the third volume, published in 1811.

Nicolas-Théodore de Saussure's Recherches chimiques sur la végétation "Chemical researches on vegetation" shows that plants require carbon dioxide from the air and nitrogen from the soil. Earlier researchers had assumed the plants got carbon from the soil instead of from the air.

John Leslie's An experimental inquiry into the nature and propagation of heat establishes that the transmission of heat through radiation has the same properties as the propagation of light.

(no entry for this year)

1805

image The field of comparative anatomy begins, with the publications of Baron Georges Cuvier's Lesson in Comparative Anatomy

image Pierre-Simon Laplace measures molecular forces in liquids and announces his theory of capillary forces.

The English chemist John Dalton develops his atomic theory, proposing that each chemical element is composed of atoms of a single unique type, and that, though they are both immutable and indestructible, they can combine to form more complex structures.

(no entry for this year)

1806

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1807

image Thomas Young introduces the concept of, and is the first to use the word, ENERGY.

(no entry for this year)

1808

image Étienne-Louis Malus discovers that reflected light is polarized and introduces the term POLARIZATION.

image 12 Feb 1809

Charles Darwin is born

image Jean Baptiste de Lamarck's theory of evolution presented with the publication of his Philosophie Zoologique, which emphasized the fundamental unity of life and the capacity of species to vary.

1809

image 12 Feb 1809

Charles Darwin is born

image Jean Baptiste de Lamarck's theory of evolution presented with the publication of his Philosophie Zoologique, which emphasized the fundamental unity of life and the capacity of species to vary.

(no entry for this year)

1810

Mary Anning's brother Joseph discovers the world's first recognized fossil ichthyosaur. Mary Anning will collect the fossil the next year.

(no entry for this year)

1811

Georges Cuvier identifies the "biblical flood" victim, described by Johann Jakob Scheuchzer in 1731, as a giant salamander.

(no entry for this year)

1812

Georges Cuvier correctly identifies pterosaurs as flying reptiles. His conclusions will be largely ignored for many years.

image William Hyde Wollaston invents the camera lucida, a device for projecting an image onto a flat surface, such as drawing paper, on which the object can then be traced.

image Swiss-French botanist Augustin Pyramus de Candolle introduces the word TAXONOMY in his lifelong project of a 21-volume plant encyclopedia. Seven volumes are published during his lifetime, the remainder after his death.

1813

image Swiss-French botanist Augustin Pyramus de Candolle introduces the word TAXONOMY in his lifelong project of a 21-volume plant encyclopedia. Seven volumes are published during his lifetime, the remainder after his death.

(no entry for this year)

1814

(no entry for this year)

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1815

Relying largely on fossils to identify strata, civil engineer William Smith publishes a geologic map of England, Wales and part of Scotland, the largest region so far documented. Four years later, Smith will be arrested and sent to debtors' prison.

(no entry for this year)

1816

image Augustin Fresnel demonstrates with his mirror experiment the wave nature of light. He also gives an explanation of polarization.

image Georges Cuvier's Le règne animal distribué d'après son organisation (The animal kingdom, distributed according to its organization) gives an account of the whole animal kingdom, dividing it into four distinct groups.

1817

Russian biologist Heinz Christian Pander studies the chick embryo and discovers the germ layers (i.e., three distinct regions of the embryo that give rise to the specific organ systems). Because of these findings, he is considered by many to be the "founder of embryology".

image Georges Cuvier's Le règne animal distribué d'après son organisation (The animal kingdom, distributed according to its organization) gives an account of the whole animal kingdom, dividing it into four distinct groups.

image image Thomas Young and Augustin Fresnel demonstrated that light waves must be transverse vibrations.

(no entry for this year)

1818

(no entry for this year)

image Christian Friedrich Nasse formulated Nasse's law: hemophilia occurs only in males and is passed on by unaffected females.

1820

image Christian Friedrich Nasse formulated Nasse's law: hemophilia occurs only in males and is passed on by unaffected females.

Gideon Mantell discovers, in England, a fossil trunk of a tree resembling that of a tropical palm, evidence of a much warmer climate.

image André-Marie Ampère formulates one of the basic laws of electromagnetism, the right-hand rule for the influence of an electric current on the magnet and demonstrates that two wires that are carrying an electric current will attract or repel each other, depending on whether the occurrence are in opposite where the same directions.

image Dominique-François Arago discovers the magnetic effect of electricity passing through a copper wire, demonstrating that iron is not necessary for magnetism.

image Augustin-Jean Fresnel invents the so-called Fresnel lens, a lens used in lighthouses.

image The science of electrodynamics is born with the announcement of Hans Christian Ørsted's discovery of electromagnetism.

(no entry for this year)

1821

(no entry for this year)

Etienne Geoffroy publishes Anatomical Philosophy discussing similarities between skeletal structures — such as bat wings, paws and hands — that support the evolutionary claims of Lamarck. He also argues that arthropods and vertebrates have similar but inverse body plans, an assertion that will ultimately be widely accepted.

image Between 1822-1824, Thomas Andrew Knight, John Goss, and Alexander Seton all independently perform crosses with the pea and observe dominance in the immediate progeny, and segregation of various hereditary characters in the next generation. However, they do not study later generations or determine the numerical ratios in which the characters are transmitted.

1822

Etienne Geoffroy publishes Anatomical Philosophy discussing similarities between skeletal structures — such as bat wings, paws and hands — that support the evolutionary claims of Lamarck. He also argues that arthropods and vertebrates have similar but inverse body plans, an assertion that will ultimately be widely accepted.

image Between 1822-1824, Thomas Andrew Knight, John Goss, and Alexander Seton all independently perform crosses with the pea and observe dominance in the immediate progeny, and segregation of various hereditary characters in the next generation. However, they do not study later generations or determine the numerical ratios in which the characters are transmitted.

William Buckland publishes an account of how ancient hyenas lived and fed in Kirkdale Cave, based on their fossil remains. This is one of the first descriptions of living habits based on fossil evidence.

Omalius d'Halloy names the Cretaceous System, after massive chalk deposits. This time period will later be identified with the last dinosaurs and the first flowering plants.

William Conybeare and William Phillips name the Carboniferous System, a period associated with coal deposits. This time period will also become known as the Mississippian and Pennsylvanian Periods in the United States.

image Thomas Andrew Knight confirms reports of dominance, recessivity, and segregation in peas, but does not detect regularities.

1823

image Thomas Andrew Knight confirms reports of dominance, recessivity, and segregation in peas, but does not detect regularities.

William Buckland finds a skeleton covered in ocher. Called the Red Lady, it will later be identified as Cro-Magnon (and male).

(no entry for this year)

1824

William Buckland publishes Notice on the Megalosaurus ("giant lizard"), the first dinosaur fossil to be described and named, although the term "dinosaur" doesn't yet exist. Buckland also announces the discovery of the first fossil mammal from the Mesozoic.

image Réflexions sur la puissance motrice du feu (On the motive power of fire) by Nicolas Léonard Sadi Carnot shows that work is done as heat passes from a high temperature to a low temperature; defines work; hints at the second law of thermodynamics; and suggests internal combustion engines.

(no entry for this year)

1825

Father John MacEnery starts digging in Kent's Cave in Devon. He'll eventually find human remains in the same layer as those of extinct mammals, a finding that will be dismissed by Buckland.

Gideon Mantell publishes Notice on the Iguanodon, the second description of a dinosaur and the first description of an herbivorous fossil reptile.

(no entry for this year)

1826

(no entry for this year)

image Karl Ernst von Baer first demonstrated the mammalian ovum; he regarded the sperm cells as "Entozoa," i.e., parasites, and named them spermatozoa.

1827

image Karl Ernst von Baer first demonstrated the mammalian ovum; he regarded the sperm cells as "Entozoa," i.e., parasites, and named them spermatozoa.

image Theory of systems of rays by William Rowan Hamilton is a unification of the study of optics through the principle of "varying action". It contains his correct prediction of conical refraction. When his prediction is verified, he becomes a well-known and is knighted.

image While studying the behavior of fluids under a microscope, botanist Robert Brown (1773-1858) discovers what is today called "Brownian motion".

A year after discovering the mammalian egg cell, Karl Ernst von Baer publishes Entwickelungsgeschichte der Thiere tracing the developmental history of animals.

image Publication of Karl Ernst von Baer's The Embryology of Animals which strongly opposed preformationism.

1828

A year after discovering the mammalian egg cell, Karl Ernst von Baer publishes Entwickelungsgeschichte der Thiere tracing the developmental history of animals.

image Publication of Karl Ernst von Baer's The Embryology of Animals which strongly opposed preformationism.

Adolphe Brongniart publishes Prodrome d'une histoire des Végétaux Fossils, a study of fossil plants. He outlines four distinct phases in plant prehistory: (1) primitive plants from the Coal Measures, (2) the first conifers, (3) domination by cycads and conifers, and (4) flowering plants.

Mary Anning discovers Britain's first recognized pterosaur fossil. (Gideon Mantell has already found pterosaur remains, but has attributed them to a bird).

image Chemist Friedrich Wöhler (1800-1882) synthesizes the organic compound urea, a feat previously thought impossible because of the vital force thought to be a part of organic substances.

(no entry for this year)

1829

Philippe-Charles Schmerling discovers a Neanderthal fossil, the partial cranium of a small child. The fossil will not be accurately identified as Neanderthal, however, for a century, though Charles Lyell will illustrate it in Antiquity of Man in 1863.

Jules Desnoyers names the Quaternary System, a time in which humans have lived.

image Gustave-Gaspard Coriolis coins the term KINETIC ENERGY in On the calculation of mechanical action.

image Joseph Henry shows that passing an electric current through a wire wrapped into coils produces a greater magnetic field than is produced when that same current is passed through a straight wire, and that an insulated wire wrapped around an iron core can produce a powerful electromagnet.

image Charles Lyell's multi-volume Principles of Geology appear (between 1830 amd 1833), advancing the theory of uniformitarianism, i.e., the view that geological formations are explainable in terms of forces and conditions observable at present.

1830

image Charles Lyell's multi-volume Principles of Geology appear (between 1830 amd 1833), advancing the theory of uniformitarianism, i.e., the view that geological formations are explainable in terms of forces and conditions observable at present.

Georg Goldfuss announces that he sees "hairs" on a pterosaur fossil. This outlandish assertion will be supported by later finds.

image The first edition of Birds of America, by the painter and ornithologist John James Audubon (1785-1851), appears.

image Charles Darwin joins the crew of the HMS Beagle as the ship's naturalist. The Beagle plans a two-year voyage to map the coast of South America. This turns out to be a five-year trip.

Patrick Matthew publishes On Naval Timber and Arboriculture with an appendix describing what Charles Darwin will later name natural selection. After becoming aware of Matthew's hypothesis, Darwin will acknowledge it in a reprint of On the Origin of Species.

image Robert Brown published his observations reporting the discovery and widespread occurrence of nuclei in cells.

1831

image Charles Darwin joins the crew of the HMS Beagle as the ship's naturalist. The Beagle plans a two-year voyage to map the coast of South America. This turns out to be a five-year trip.

Patrick Matthew publishes On Naval Timber and Arboriculture with an appendix describing what Charles Darwin will later name natural selection. After becoming aware of Matthew's hypothesis, Darwin will acknowledge it in a reprint of On the Origin of Species.

image Robert Brown published his observations reporting the discovery and widespread occurrence of nuclei in cells.

Independently, Michael Faraday and Joseph Henry discover that electricity can be induced by changes in a magnetic field (electromagnetic induction), a discovery leading to the first electric generators.

Encouraged by Cambridge professor William Whewell, the Royal Society of London commissions reports of manuscripts received. This move will later be cited as the beginning of the peer-review process.

(no entry for this year)

1832

Gideon Mantell finds the first fossil Hylaeosaurus, an ankylosaur. He will formally name it the following year, making it the third identified dinosaur species.

image The first volume of the five-volume Recherches sur les poissons fossiles (Researches on Fossil Fishes) by Jean-Louis-Rodolphe Agassiz is published.

1833

Solicitor André Brouillet discovers a reindeer bone with an engraved illustration of two female deer in Chaffaud Cave. He assumes the carving was made by the Celts. Later research will show the artwork to be about 13,000 years old.

image The first volume of the five-volume Recherches sur les poissons fossiles (Researches on Fossil Fishes) by Jean-Louis-Rodolphe Agassiz is published.

image The English term SCIENTIST is coined by the philosopher William Whewell (1794-1866 ), during a meeting of the British Association for the Advancement of Science.

image image In correspondence, Michael Faraday and William Whewell introduce the terms ELECTRODE, ANODE, ION, CATHODE, ANION, CATION, ELECTROLYTE, and ELECTROLYSIS.

(no entry for this year)

1834

Based on a vertebrae and other fragments from Alabama, anatomist Richard Harlan identifies Basilosaurus as a fossil reptile. It will later be identified as a fossil whale.

Friedrich von Alberti names the Triassic System. This time period will later by identified with the first dinosaurs.

image Mathematician Carl Friedrich Gauss (1777-1855) shows that the origin of the Earth's magnetic field must lie deep inside the Earth. He makes use of the measurements of the magnetic field made by the physicist Paul Erman in 1828.

image While serving as scientific officer on the HMS Beagle, Charles Darwin visits the Galapagos Islands. He observes that the many varieties of finches on the islands seem to have developed from a common ancestor found on the mainland of South America.

1835

image While serving as scientific officer on the HMS Beagle, Charles Darwin visits the Galapagos Islands. He observes that the many varieties of finches on the islands seem to have developed from a common ancestor found on the mainland of South America.

Adam Sedgwick names the Cambrian System, recognizing the first rich assemblage of fossils in the rock record. Roderick Murchison names the Silurian System. He believes (not entirely accurately) that the Silurian predates the fossils of land plants, and consequently any economically valuable coal seams. Murchison and Sedgwick will later develop a bitter priority dispute over these systems.

image Gustave-Gaspard Coriolis's Mémoire sur les equations du mouvement relatif des sytèms de corps (Memoir on the equations of relative movement of systems of bodies) describes the Coriolis effect: the deflection of a moving body caused by Earth's rotation. The Coriolis effect is important in the study of wind. However, the claim that the Coriolis effect determines the direction water rotates when going down a drain is a myth.

(no entry for this year)

1836

image image Mappa Selenographica, a map of the moon's surface, is produced by the astronomers Wilhelm Beer (1797-1850) and Johann Heinrich von Mädler (1794-1874). The two will also be the first to map Mars.

Henry Riley and Samuel Stutchbury name Thecodontosaurus, the fourth named dinosaur species.

image Elements of Botany, by the naturalist Asa Gray (1810-1888), is published. It is the first botanical textbook.

image German biologist Theodor Schwann discovers the enzyme pepsin — the first known animal enzyme. He reports the discovery in Über das Wesen der Verdauungsprozesses (On the essence of digestion).

image John Frederic Danielle invents the Daniell cell, the first reliable source of electric current, based on the interactions of copper and zinc.

Charles Darwin formulates the theory of natural selection to explain evolution. Fearful of the reaction his theory will cause, he delays publishing.

1837

Charles Darwin formulates the theory of natural selection to explain evolution. Fearful of the reaction his theory will cause, he delays publishing.

Hermann von Meyer names Plateosaurus, the fifth named dinosaur species.

Louis Agassiz presents the theory of the Ice Age at a meeting of the Swiss Society of Natural Sciences. The shocked audience reacts with hostility.

image Mathematician Semèon Denis Poisson (1781-1840) publishes Recherches sur la Probabilitè des Jugements. Poisson's book described what is now known as the Poisson Distribution, for the first time.

image image M. J. Schleiden and T. Schwann develop the cell theory. Schleiden notes nucleoli within nuclei.

1838

image image M. J. Schleiden and T. Schwann develop the cell theory. Schleiden notes nucleoli within nuclei.

image Chemist Jöns Jakob Berzelius (1779-1848) shows that the presence of iron is what enables blood to absorb as much oxygen as it does.

image image The word PROTEIN first appears in the chemical literature in a paper by G. J. Mulder. The term, however, was invented by J. J. Berzelius.

(no entry for this year)

1839

image Czech scientist Jan Evangelista Purkyně (also written Johannes Evangelist Purkinje) coins the word PROTOPLASM to describe the contents of a cell.

Roderick Murchison and Adam Sedgwick name the Devonian System.

The English scientist Michael Faraday concludes from his work on electromagnetism that, contrary to scientific opinion of the time, the divisions between the various kinds of electricity are illusory. He also establishes that magnetism can affect rays of light, and that there is an underlying relationship between the two phenomena.

image Charles Darwin's Zoology of the Voyage of the Beagle appears.

Martin Barry expressed the belief that the spermatozoon enters the egg.

1840

image Charles Darwin's Zoology of the Voyage of the Beagle appears.

Martin Barry expressed the belief that the spermatozoon enters the egg.

image Alexandre-Edmond Becquerel shows that light can initiate chemical reactions that produce an electric current.

(no entry for this year)

1841

Roderick Murchison names the Permian System.

William Smith's nephew John Phillips formally proposes the geologic eras Paleozoic, Mesozoic and Cainozoic (Cenozoic).

image Charles Thomas Jackson (1805-1880) discovers the anesthetic properties of ether.

image Charles Darwin's book The Structure and Distribution of Coral Reefs being the first part of the geology of the voyage of the Beagle, is published. During the year Darwin composes an abstract of his theory of species evolution.

image Carl Wilhelm von Nägeli (1817-1891) publishes Zur Entwicklungsgeschichte des Pollens. His paper describes cell division in plants with remarkable accuracy, and discusses seed formation in flowering plants.

1842

image Charles Darwin's book The Structure and Distribution of Coral Reefs being the first part of the geology of the voyage of the Beagle, is published. During the year Darwin composes an abstract of his theory of species evolution.

image Carl Wilhelm von Nägeli (1817-1891) publishes Zur Entwicklungsgeschichte des Pollens. His paper describes cell division in plants with remarkable accuracy, and discusses seed formation in flowering plants.

Richard Owen names Cetiosaurus, the sixth named dinosaur species.

image Die Thierchemie, by chemist Baron Justus von Liebig (1803-1873), is published, and the science of biochemistry begins.

image The term DINOSAUR is coined by Richard Owen (1804-1892) to describe a class of animals that we now believe were dominant on the Earth for approximately 175 million years.

Based on Agassiz's Ice Age theory, self-taught science enthusiast Charles MacLaren publishes a newspaper article explaining that substantial ice sheets in the northern hemisphere would have lowered global sea level.

image German physician and physicist Julius Robert Mayer is the first to state the law of conservation of energy, noting specifically that heat and mechanical energy are two aspects of the same thing.

image On the uniform motion of heat in homogeneous solid bodies, by William Thomson, aka Lord Kelvin (1824-1907), is published. Thomson's concern with the physics of cooling bodies will draw him into debates concerning the age of the Earth. In 1846 he calculates that the Earth can be no more than 100 million years old.

image The change in the observed frequency of waves emitted from a source, moving relative to the observer, is described by Christian Johann Doppler (1803-1853). This phenomenon is now known as the Doppler Effect.

(no entry for this year)

1843

Louis Agassiz completes Les Poissons Fossiles describing fossil fish of the world. This single monograph increases tenfold the formally described vertebrates known to science.

image That the nervous system uses electricity in communicating between different parts of the body is demonstrated by Emil Heinrich du Bois-Reymond (1818-1896). He founds the field of electrophysiology.

image John Stuart Mill publishes Logic.

image James Prescott Joule determines the mechanical equivalent of heat by measuring the rise in temperature produced in water by stirring it.

image Charles Darwin first outlines his thoughts on natural selection in an unpublished essay.

image Robert Chambers, a Scottish journalist, publishes (anonymously) his Vestiges of the Natural History of Creation, an early book outlining an evolutionary view of the natural world.

image The second part of the Geology of the Beagle, Charles Darwin's Geological Observations on Volcanic Islands Visited During the Voyage of H.M.S. Beagle, is published. Darwin's book claims to supply evidence for the geological theories of Charles Lyell (1797-1875), from areas that Lyell himself had never seen.

image That all the cells in an organism are generated from successive divisions of the egg cell is described by Rudolf Albert von Kölliker (1817-1905). Kölliker shows that the egg is itself a cell.

1844

image Charles Darwin first outlines his thoughts on natural selection in an unpublished essay.

image Robert Chambers, a Scottish journalist, publishes (anonymously) his Vestiges of the Natural History of Creation, an early book outlining an evolutionary view of the natural world.

image The second part of the Geology of the Beagle, Charles Darwin's Geological Observations on Volcanic Islands Visited During the Voyage of H.M.S. Beagle, is published. Darwin's book claims to supply evidence for the geological theories of Charles Lyell (1797-1875), from areas that Lyell himself had never seen.

image That all the cells in an organism are generated from successive divisions of the egg cell is described by Rudolf Albert von Kölliker (1817-1905). Kölliker shows that the egg is itself a cell.

(no entry for this year)

1845

The School of Medicine in Paris creates a gallery of comparative anatomy.

image Michael Faraday relates magnetism to light after finding the magnetic field effects the polarization of light in crystals. He proposes that light may be waves of electromagnetism. He also describes the phenomena of diamagnetism and paramagnetism, which he explains in terms of his concept of a magnetic field.

(no entry for this year)

1846

image Karl Wilhelm Von Nägeli shows that plant cells are not formed as buds from the surfaces of existing cells, as was proposed by Theodore Schwann.

Joseph Leidy identifies in pork the parasite that causes trichinosis, a potentially fatal human disease.

image James Prescott Joule discovers that the length of an iron bar changes slightly when the bar is magnetized.

Jakob Mathias Schleiden and Theodor Schwann announce that cells are the basic units of all living structures.

1847

Jakob Mathias Schleiden and Theodor Schwann announce that cells are the basic units of all living structures.

image In his Account of a New Anesthetic Agent, obstetrician Sir James Simpson (1811-1870) argues that chloroform, a substance he discovered, is a better anesthetic than nitrous oxide or ether. Simpson has begun to use chloroform as an anesthetic in childbirth.

image Über die Erhaltung der Kraft ("On the Conservation of Force"), by Hermann Ludwig von Helmholtz (1821-1894), is published. It articulates what later becomes known as the Conservation of Energy.

image On the archetype and homologies of the vertebrate skeleton, by Richard Owen (1804-1892), is published. In the book Owen argues that the skull, and other parts of the body, are formed by the modification of the vertebra of different animals.

Richard Owen describes "homologies" — similarities of design in bird wings, fish fins and human hands.

1848

image On the archetype and homologies of the vertebrate skeleton, by Richard Owen (1804-1892), is published. In the book Owen argues that the skull, and other parts of the body, are formed by the modification of the vertebra of different animals.

Richard Owen describes "homologies" — similarities of design in bird wings, fish fins and human hands.

A Neanderthal skull is excavated from Forbes Quarry on the northern side of the Rock of Gibraltar. Over the next few decades, the skull will be stashed in a library cabinet in Gibraltar, dusted off and sent to London, accurately likened to the ancient skullcap from Neander Valley in Germany, nearly named Homo calpicus, and finally stored and largely forgotten in the Royal College of Surgeons.

The American Medical Association is founded in Philadelphia, with a mission "to promote the science and art of medicine and the betterment of public health."

image An absolute scale of temperatures is proposed by William Thomson (1824-1907). Thomson will become Baron Kelvin of Largs, in 1892, and the scale will come to bear his name.

image Armand Hippolyte Louis Fizeau suggests that light from a source of moving away from the observer will be shifted toward the red end of the spectrum, a phenomenon known as redshift. This is closely related to, but not exactly the same as, the Doppler effect.

image The American Association for the Advancement of Science is founded. Joseph Henry (1797-1898), who had been appointed the first secretary of the Smithsonian in 1846, is the first secretary of the AAAS, which is modeled after The British Association for the Advancement of Science. The British Association has been in existence for 17 years.

The American Association for the Advancement of Science is established.

image Botanist Carl Friedrich von Gärtner (1772-1850) publishes Versuche und Beobachtungen über die Bastarderzeugung im Pflanzenreiche. The book describes thousands of experiments, many involving the production of hybrids, on more than 500 species of plants. Mendel will study this book in detail when he attends the University of Vienna in the early 1850s, and will cite the book in the opening of his paper of 1865.

1849

image Botanist Carl Friedrich von Gärtner (1772-1850) publishes Versuche und Beobachtungen über die Bastarderzeugung im Pflanzenreiche. The book describes thousands of experiments, many involving the production of hybrids, on more than 500 species of plants. Mendel will study this book in detail when he attends the University of Vienna in the early 1850s, and will cite the book in the opening of his paper of 1865.

Based on a humerus 58 inches in circumference, Mantell names a new dinosaur species: Pelorosaurus, the first recognized sauropod.

image Armand Hippolyte Louis Fizeau measures the velocity of light in error by measuring the time it takes for a beam of light to pass between the teeth of a rotating gear. The light is reflected by a mirror and stopped by the next tooth of the gear. The result, 315,000 km/se4c (196,000 miles/sec), is within 5% of today's accepted value.

image In describing Sadi Carnot's theory of heat, published in 1824, William Thomson (1824-1907) uses the term THERMODYNAMICS.

image The speed of light is measured by physicist Armand Hippolyte Louis Fizeau (1819-1896) to be approximately 186,000 miles per second.

(no entry for this year)

1850

image German physicist Gustav Theodor Fechner discovers that an increase in the intensity of a stimulus does not produce a one-to-one increase in the intensity of sensation. Instead, the sensation seems to increase as the logarithm of the excitation.

image Mathematician Bernard Bolzano's Paradoxien des Unendlichen is published, two years after the Bolzano's death. It is the first work to use the word "set" in a modern mathematical sense, and also treats infinite sets.

image In Über die bewegende Kraft der Wärme, mathematical physicist Rudolf Julius Emanuel Clausius articulates what comes to be known as the Second Law of Thermodynamics. The law states that heat can only be transferred from a warmer body to a colder body. In 1865, he'll restate the Law, saying that in the closed system entropy always increases.

(no entry for this year)

1851

image Mathematician Joseph Liouville demonstrates the existence of transcendental numbers (transcendentals are numbers that are not the solution to any algebraic equation).

image Léon Foucault demonstrates that the Earth rotates using a pendulum, suspended from the ceiling of a church.

image Physicist William Thomson proposes a concept of "absolute zero", at which the energy of molecules is zero. He draws on Charles' Law to show that such a condition would hold at -273 degrees Celsius.

(no entry for this year)

1852

image Albrecht von Kölliker publishes the first textbook of histology, Handbuch der Gewebelehre.

image Hermann Ludwig von Helmholtz becomes the first to discover how fast a message travels along a nerve, measuring the speed of transmission in a frog nerve cell.

image image James Prescott Joule and William Thompson, later Lord Kelvin, establish that an expanding gas becomes cooler. This is now known as the Joule-Thompson effect.

(no entry for this year)

1853

image Rudolph Albert von Kölliker discovers the cellular origin of spermatozoa, which were believed by some to originate from a fermentation process.

In Britain, vaccination against small pox is made compulsory.

image Léon Foucault demonstrates that the velocity of light is lesson water than in air, tending to confirm the wave theory of light.

image William John Macquorn Rankine introduces the concept of potential energy, or energy of position.

(no entry for this year)

1854

image Mathematician George Boole, whose "Calculus of Logic," appeared in 1848, publishes An Investigation of the Laws of Thought, on Which are Founded the Mathematical Theories of Logic and Probabilities, which articulates a system of "symbolic logic".

image Alfred Russel Wallace publishes "On the Law which has Regulated the Introduction of New Species," anticipating Darwin's theory of evolution by natural selection.

image Rudolf Virchow states the principle that new cells come into being only by division of previously existing cells: Omnis cellula e cellula.

1855

image Alfred Russel Wallace publishes "On the Law which has Regulated the Introduction of New Species," anticipating Darwin's theory of evolution by natural selection.

image Rudolf Virchow states the principle that new cells come into being only by division of previously existing cells: Omnis cellula e cellula.

image Recherches sur la putréfaction, by Louis Pasteur, is published. The book describes how fermentation is caused by microorganisms.

image The remains of the first known example of what come to be known as the "Neanderthals" is found in a cave near Düsseldorf, in the Neander Valley. The discovery was made by limestone quarry miners and consists of a skullcap, two femora, the three right arm bones, two of the left arm bones, ilium, and fragments of a scapula and ribs. The fossils were given to Johann Carl Fuhlrott, a local teacher and amateur naturalist. The first description of the remains was made by anatomist Hermann Schaaffhausen and the find was announced jointly in 1857.In 1997, the specimen was the first to yield Neanderthal mitochondrial DNA fragments. The description of this discovery represents the beginning of paleoanthropology as a scientific discipline.

Louis Agassiz publishes Essay on Classification advocating a theory of multiple creations and contradicting both evolution and Noah's ark.

image Gregor Mendel, a monk at the Augustinian monastery of St. Thomas in Brünn, Austria (now Brno, Czechoslovakia), begins breeding experiments with the garden pea, Pisum sativum.

1856

image The remains of the first known example of what come to be known as the "Neanderthals" is found in a cave near Düsseldorf, in the Neander Valley. The discovery was made by limestone quarry miners and consists of a skullcap, two femora, the three right arm bones, two of the left arm bones, ilium, and fragments of a scapula and ribs. The fossils were given to Johann Carl Fuhlrott, a local teacher and amateur naturalist. The first description of the remains was made by anatomist Hermann Schaaffhausen and the find was announced jointly in 1857.In 1997, the specimen was the first to yield Neanderthal mitochondrial DNA fragments. The description of this discovery represents the beginning of paleoanthropology as a scientific discipline.

Louis Agassiz publishes Essay on Classification advocating a theory of multiple creations and contradicting both evolution and Noah's ark.

image Gregor Mendel, a monk at the Augustinian monastery of St. Thomas in Brünn, Austria (now Brno, Czechoslovakia), begins breeding experiments with the garden pea, Pisum sativum.

Heinz Christian Pander describes conodonts — toothy microfossils that will puzzle paleontologists for many years.

(no entry for this year)

1857

image Über die Art der Bewegung, welche wir Wäe nennen (On the type of motion turned heat) by Rudolf Clausius is establishes his kinetic theory of heat of the mathematical basis. It also explains how evaporation occurs.

Rudolf Virchow finalizes the cell theory originally announced by Schleiden and Schwann 11 years earlier by declaring that cells are the basic units of all living things, and all cells are formed by the division of existing cells.

image Alfred Russel Wallace sends to Darwin a manuscript — "On the Tendency of Varieties to Depart Indefinitely from the Original Type" — that shows clearly that Wallace has independently formulated a model of evolution by natural selection.

image image Darwin's and Wallace's ideas are jointly presented to the Linnaean Society of London.

1858

Rudolf Virchow finalizes the cell theory originally announced by Schleiden and Schwann 11 years earlier by declaring that cells are the basic units of all living things, and all cells are formed by the division of existing cells.

image Alfred Russel Wallace sends to Darwin a manuscript — "On the Tendency of Varieties to Depart Indefinitely from the Original Type" — that shows clearly that Wallace has independently formulated a model of evolution by natural selection.

image image Darwin's and Wallace's ideas are jointly presented to the Linnaean Society of London.

The first relatively complete dinosaur skeleton, of Hadrosaurus foulkii, is found in New Jersey.

image Physician Henry Gray publishes Anatomy of the Human Body, Descriptive and Surgical. Gray's Anatomy will be a standard textbook of anatomy for more than a century.

image The concept of "bonds" is introduced by chemist Archibald Scott Couper, who believes that carbon atoms are the fundamental building blocks of organic compounds.

image Julius Plücker shows that cathode rays bend under the influence of a magnet, suggesting they are connected in some way with charge. This is an early step along the path that will lead in 1897 to the discovery that cathode rays are composed of electrons.

image Charles Darwin publishes On the Origin of Species.

1859

image Charles Darwin publishes On the Origin of Species.

An exceptionally well-preserved skeleton is discovered in Bavaria. Two years later, this bird-like, bipedal dinosaur will be named Compsognathus, meaning "dainty jaw."

Catholic priest Jean-Jacques Pouech describes fossil eggshell fragments. They will eventually prove to be the first described dinosaur eggs.

image Matrix algebra begins, as mathematician Arthur Cayley discusses the matrix in the context of a theory of invariant transformations.

image Gustav Kirchoff recognizes that sodium is found on the sun and discovers his black-body radiation law.

image image Physicist Gustav Robert Kirchhoff and chemist R. W. Bunsen explain that when light passes through a gas, or heated material, only certain wavelengths of the light are absorbed. Therefore, an analysis of the spectrum of the light can reveal the chemical makeup of the gas or material.

image Louis Agassiz attacks Darwin's the origin of species, rejecting the idea of evolution of the species and arguing that each species was created separately.

image Thomas Henry Huxley (sometimes known as Darwin's bulldog) clashes with Bishop "Soapy Sam" Wilberforce about evolution at the annual meeting of The British Association for the Advancement of Science, in what has come to be known as the Huxley-Wilberforce debate.

Bishop Wilberforce is supposed to have asked Huxley sarcastically whether "it was through his grandfather or his grandmother that he claimed descent from a monkey." Huxley responded, "If then the question is put to me whether I would rather have a miserable ape for a grandfather or a man highly endowed by nature and possessed of great means of influence and yet employs these faculties and that influence for the mere purpose of introducing ridicule into a grave scientific discussion, I unhesitatingly affirm my preference for the ape." Or words to that effect.

1860

image Louis Agassiz attacks Darwin's the origin of species, rejecting the idea of evolution of the species and arguing that each species was created separately.

image Thomas Henry Huxley (sometimes known as Darwin's bulldog) clashes with Bishop "Soapy Sam" Wilberforce about evolution at the annual meeting of The British Association for the Advancement of Science, in what has come to be known as the Huxley-Wilberforce debate.

Bishop Wilberforce is supposed to have asked Huxley sarcastically whether "it was through his grandfather or his grandmother that he claimed descent from a monkey." Huxley responded, "If then the question is put to me whether I would rather have a miserable ape for a grandfather or a man highly endowed by nature and possessed of great means of influence and yet employs these faculties and that influence for the mere purpose of introducing ridicule into a grave scientific discussion, I unhesitatingly affirm my preference for the ape." Or words to that effect.

John Phillips diagrams the progressive but fluctuating diversity of life on Earth based on the fossil record. His work evidences massive extinctions at the end of the Paleozoic and Mesozoic, and increased diversity in each subsequent age.

image Louis Pasteur becomes significantly involved in biological research with the publication of "Mémoir sur la fermentation alcoolique" in which he showed that alcoholic fermentation seemed to be carried out by yeast, which were themselves living organisms.

image image Between 1861 and 1862, Max Johann Sigismund Schultze (Germany) and Heinrich Anton de Bary (Germany) establish the essential unity of protoplasm in all living cells.

1861

image image Between 1861 and 1862, Max Johann Sigismund Schultze (Germany) and Heinrich Anton de Bary (Germany) establish the essential unity of protoplasm in all living cells.

image First recognized fossil Archaeopteryx lithographica skeleton is found in the stone quarries of Solnhofen.

image In "Mémoires sur les corpuscles organisés qui existent dans l'atmosphère," Pasteur applies heat to bent-neck flasks to show unequivocally that the "organized bodies" (microbes) which drive fermentation originate from "organized bodies" that exist in the atmosphere. In this elegant series of experiments, Pasteur laid to rest the long-held belief in spontaneous generation."

In his presidential address to the Geological Society of London, Leonard Horner proposes removing the world's "creation" date of 4004 BC from the English Bible, citing geological evidence of a much older planet.

(no entry for this year)

1862

Lord Kelvin asserts that the Earth and sun are cooling from their initial formation, between 20 and 400 million years ago. He will later adopt the smaller number.

Alfred Russel Wallace describes the "Wallace line," the dividing line between Indo-Malayan and Austro-Malayan fauna, in Proceedings of the Royal Geographical Society of London.

image image Dominique Alexandre Godron and Charles Victor Naudin (France) independently report experiments in plant hybridization. Naudin confirmed Sageret's work, in general discussed work of the early hybridizers, and reported dominance and segregation in Datura (jimsonweed) hybrids. He did not deal with single characters and reported no statistical observations on the second generation. His theoretical explanation of his facts was a forerunner of Mendel's ideas, but inferred rather than deduced.

1863

Anti-evolutionist James Hunt, founder of the Anthropological Society of London, gives a presidential address to the society stating that human races were created separately. He further argues that the African species is closer in ability to apes than to Europeans.

Alfred Russel Wallace describes the "Wallace line," the dividing line between Indo-Malayan and Austro-Malayan fauna, in Proceedings of the Royal Geographical Society of London.

image image Dominique Alexandre Godron and Charles Victor Naudin (France) independently report experiments in plant hybridization. Naudin confirmed Sageret's work, in general discussed work of the early hybridizers, and reported dominance and segregation in Datura (jimsonweed) hybrids. He did not deal with single characters and reported no statistical observations on the second generation. His theoretical explanation of his facts was a forerunner of Mendel's ideas, but inferred rather than deduced.

T. H. Huxley publishes Man's Place in Nature discussing human and primate paleontology, and showing similarities between humans and other animals.

image Father-and-son glassworkers Leopold and Rudolf Blaschka begin making glass models of marine invertebrates. Marine biologists will refer to their exquisitely detailed, accurate models 150 years later while trying to see how many of the depicted species can still be found in the wild.

Abraham Lincoln forms the National Academy of Sciences.

(no entry for this year)

1864

image Ernst Haeckel (Häckel) outlines the essential elements of modern zoological classification.

image James Clerk Maxwell's A dynamical theory of the electromagnetic field is the first of his publications to use Michael Faraday's concept of a field as the basis of the mathematical treatment of electricity and magnetism. It introduces Maxwell's equations to describe electromagnetism.

Franz Schweigger-Seidel and A. von la Valette St. George (Germany) independently prove that a spermatozoon is a single cell and contains nucleus and cytoplasm

image Gregor Mendel presents his work on inheritance in peas to the Brünn Natural History Society. The results are published the following year.

1865

John Lubbock publishes Prehistoric Times dividing what has previously been understood to be the Stone Age into two parts: the older Paleolithic and the newer Neolithic. In the same book, he also argues that modern Tasmanians and Fuegians are throwbacks to archaic humans.

Franz Schweigger-Seidel and A. von la Valette St. George (Germany) independently prove that a spermatozoon is a single cell and contains nucleus and cytoplasm

image Gregor Mendel presents his work on inheritance in peas to the Brünn Natural History Society. The results are published the following year.

Sir John William Dawson of McGill University identifies "shells" of huge foraminiferal protozoans. Known as Eozoön or "dawn animal," this find is used as an argument against evolution because it shows a relatively "modern" animal early in the fossil record. It will prove, however, to be a geologically young pseudofossil formed by heat and pressure on limestone.

Paolo Mantegazza publishes Degli Innesti Animali e della Produzione Artificiale delle Cellule (On Animal Grafts and Artificial Cell Production) describing the results of a series of interspecies animal grafts, such as the transplant of a cockspur onto a cow ear. Grafts described include transplants between dogs, frogs and rodents. Mantegazza reports that some grafts decomposed while others became "pathological tumours."

image Rudolf Clausius invents the term ENTROPY to describe the degradation of energy in the closed system.

German zoologist Ernst Haeckel publishes General Morphology of Organisms, the first detailed genealogical tree relating all known organisms, incorporating the principles of Darwinian evolution.

image Ernst Heinrich Haeckel (Häckel) hypothesizes that the nucleus of a cell transmits its hereditary information.

image Mendel publishes his work on heredity, Versuche über Pflanzen Hybriden.

1866

German zoologist Ernst Haeckel publishes General Morphology of Organisms, the first detailed genealogical tree relating all known organisms, incorporating the principles of Darwinian evolution.

image Ernst Heinrich Haeckel (Häckel) hypothesizes that the nucleus of a cell transmits its hereditary information.

image Mendel publishes his work on heredity, Versuche über Pflanzen Hybriden.

image Ernst Heinrich Haeckel (Häckel) first used the term ECOLOGY to describe the study of living organisms and their interactions with other organisms and with their environment.

H. S. Bidwell (United States) reports controlled pollination in maize.

1867

Orléans Railway Company employee Peccadeau de l'Isle presents a paper to the French Academy of Sciences on his recent discoveries at Montastruc, including a mammoth carved from a reindeer antler, and two reindeer (found in separate pieces) carved from a mammoth tusk. The finds will eventually be dated at about 13,000 years old.

H. S. Bidwell (United States) reports controlled pollination in maize.

image Charles Darwin publishes The Variation of Animals and Plants under Domestication, in which he offers his own theory of heredity, which he called the "Provisional Hypothesis of Pangenesis."

Ernst Haeckel publishes Natürliche Schöpfungsgeschichte, subdividing humanity into 12 separate species. He also asserts that evolution consists of 22 phases, the 21st being the "missing link" between apes and humans.

Thomas Henry Huxley publishes "On the Animals which are Most Nearly Intermediate between Birds and Reptiles," arguing that birds are descendants of dinosaurs. This suggestion will not be taken very seriously for another century.

1868

image Charles Darwin publishes The Variation of Animals and Plants under Domestication, in which he offers his own theory of heredity, which he called the "Provisional Hypothesis of Pangenesis."

Ernst Haeckel publishes Natürliche Schöpfungsgeschichte, subdividing humanity into 12 separate species. He also asserts that evolution consists of 22 phases, the 21st being the "missing link" between apes and humans.

Thomas Henry Huxley publishes "On the Animals which are Most Nearly Intermediate between Birds and Reptiles," arguing that birds are descendants of dinosaurs. This suggestion will not be taken very seriously for another century.

Three human skulls and other skeletal remains, roughly 30,000 years old, are discovered at a rock shelter called Cro-Magnon (old French for "big hole").

image Francis Galton publishes Hereditary Genius. In it he describes a scientific study of human pedigrees from which he concludes that intelligence has a genetic basis.

1869

image Francis Galton publishes Hereditary Genius. In it he describes a scientific study of human pedigrees from which he concludes that intelligence has a genetic basis.

Huxley, Norman Lockyer and others found Nature Magazine, which becomes one of the world's two most important scientific journals. (The other journal is Science.)

(no entry for this year)

1870

O. C. Marsh discovers the first North American pterosaur, from chalk deposits in Kansas. He calculates the wingspan at 20 feet. The following year, he will collect more fossils that confirm this calculation.

Quarry workers in the Valley Forge area discover the Port Kennedy Bone Cave, under roughly the same site where the Continental Army wintered over a century earlier. The site proves rich in Pleistocene plant and animal fossils, but will be accidentally flooded decades later. The site will be lost to science until its rediscovery after the turn of the 21st century.

The rivalry between fossil collectors O. C. Marsh and E. D. Cope turns ugly when Marsh publicly points out Cope's error in reconstructing a fossil marine reptile (putting its head on the tip of its tail). Their rivalry is the public's gain as they try to outdo each other in identifying new dinosaur species — over 130.

image Publication of Charles Darwin's Descent of Man, in which the role of sexual selection in evolution is described for the first time.

Lord Kelvin suggests that "the germs of life might have been brought to the Earth by some meteorite," an idea that will enjoy support a century later.

image Johann Friedrich Miescher isolates a substance which he calls NUCLEIN from the nuclei of white blood cells. The substance was soluble in alkalis but not in acids and came to be known as nucleic acid.

image Lambert Adolphe Jacques Quetelet showed the importance of statistical analysis for biologists and laid the foundation of biometry.

1871

image Publication of Charles Darwin's Descent of Man, in which the role of sexual selection in evolution is described for the first time.

Lord Kelvin suggests that "the germs of life might have been brought to the Earth by some meteorite," an idea that will enjoy support a century later.

image Johann Friedrich Miescher isolates a substance which he calls NUCLEIN from the nuclei of white blood cells. The substance was soluble in alkalis but not in acids and came to be known as nucleic acid.

image Lambert Adolphe Jacques Quetelet showed the importance of statistical analysis for biologists and laid the foundation of biometry.

image George Johnstone Stoney notes that the wavelengths of three lines in the hydrogen spectrum are found to have simple ratios, and anticipation of Balmer's formula, an important step towards understanding the structure of the atom.

image James Clerk Maxwell explains how his statistical theory of heat works by inventing MAXWELL'S DEMON, a mythical creature that can see and handle individual molecules. By opening a gate between two vessels containing a gas only one of fast molecules passing into one, the demon would make heat flow from cold to hot.

image Ferdinand Julius Cohn coined the term BACTERIUM and founded the study of bacteriology.

1872

image Ferdinand Julius Cohn coined the term BACTERIUM and founded the study of bacteriology.

image Anton Schneider observed and described the behavior of nuclear filaments (chromosomes) during cell division in his study of the platyhelminth Mesostoma. His account was the first accurate description of the process of mitosis in animal cells.

1873

image Anton Schneider observed and described the behavior of nuclear filaments (chromosomes) during cell division in his study of the platyhelminth Mesostoma. His account was the first accurate description of the process of mitosis in animal cells.

Francis Galton publishes a paper entitled "Hereditary Improvement" arguing that people "of really good breed" should be encouraged to reproduce while their inferiors should be discouraged from doing so. This, he argues, will improve humanity the way selective breeding improves livestock.

image James Clerk Maxwell's Electricity and Magnetism contains the basic laws of electromagnetism and predicts, in great detail, such phenomena as radio waves and pressure caused by light rays.

(no entry for this year)

1874

The Hamburg Tierpark features an "anthropological-zoological" display of Lapps acting out "daily life" with reindeer. The show draws enthusiastic crowds.

The Mütter Museum buys 139 human skulls from Viennese anatomist Joseph Hyrtl. Hyrtl has compiled the collection to show the remarkable variation within European populations, and to debunk the claims of phrenologists. The collection is unusual for the time, when most skull assemblages are aimed at emphasizing differences between ethnic groups.

image Irish physicist George J. Stoney estimates the charge of the then unknown electron to be about 10-20 coulomb, close to the modern value of 1.6021892 x 10-19. He also introduces the term ELECTRON.

image The Cavendish laboratory at Cambridge is completed. Although widely believed to have been named after the 18th-century physicist Henry Cavendish, it is, in fact, named after the entire Cavendish family, because the 19th century steel-making descendent of Henry, William Cavendish, financed the laboratory. The structure of DNA was worked out at the Cavendish many years later by Watson and Crick.

image Eduard Strasburger accurately described the processes of mitotic cell division in plants.

image Francis Galton demonstrates the usefulness of twin studies for elucidating the relative influence of nature (heredity) and nurture (environment) upon behavioral traits.

image Oscar Hertwig concludes from a study on sea urchins that fertilization in both animals and plants consists of the physical union of the two nuclei contributed by the male and female parents.

1875

image Eduard Strasburger accurately described the processes of mitotic cell division in plants.

image Francis Galton demonstrates the usefulness of twin studies for elucidating the relative influence of nature (heredity) and nurture (environment) upon behavioral traits.

image Oscar Hertwig concludes from a study on sea urchins that fertilization in both animals and plants consists of the physical union of the two nuclei contributed by the male and female parents.

Paleontologist Roberto Lawley collects a badly eroded Pliocene whale bone near Pisa, Italy, and donates it to the paleontology museum of Florence. In the 21st century, close examination will indicate boreholes of Osedax, mouthless, gutless marine worms (nicknamed zombie worms) that extract nutrients by drilling into bones.

(no entry for this year)

1876

Charles Doolittle Walcott becomes the first to successfully find and describe elusive trilobite legs, ending speculation about how the animals moved.

image Eugen Goldstein shows that the radiation in a vacuum tube produced when an electric current is forced through the tube starts at the cathode. Goldstein introduces the term CATHODE RAY to describe the light emitted.

image Hermann Fol reports watching the spermatozoan of a starfish penetrate the egg. He was able to see the transfer of the intact nucleus of the sperm into the egg, where it became the male pronucleus.

1877

image Hermann Fol reports watching the spermatozoan of a starfish penetrate the egg. He was able to see the transfer of the intact nucleus of the sperm into the egg, where it became the male pronucleus.

image A new Archaeopteryx fossil is discovered in Solnhofen, complete with a toothy jaw. This well-preserved fossil, which will become known as the Berlin Archaeopteryx, supports Huxley's previous observations about its reptilian affinities.

Comparative anatomy professor François Louis Paul Gervais undertakes thin-section microscopy studies of fossil eggs. His work will be largely forgotten until Roy Chapman Andrews discovers dinosaur eggs in Mongolia in the 1920s.

image Germ Theory of Disease: Louis Pasteur presented his Germ Theory of disease. Joseph Lister went on to initiate the practice of insuring that surgeons were clean before they conducted surgery.

image Wilhelm Friedrich Kühne proposed the term ENZYME (meaning "in yeast") and distinguished enzymes from the micro-organisms that produce them.

1878

image Wilhelm Friedrich Kühne proposed the term ENZYME (meaning "in yeast") and distinguished enzymes from the micro-organisms that produce them.

Charlotte Hill collects a well-preserved fossil butterfly, later named Prodryas persephone, from the Florissant Formation in Colorado. The fossil is about 35 million years old.

Entire skeletons of Iguanodon are discovered in Belgium, enabling a more accurate reconstruction of this dinosaur than those of Owen and Waterhouse Hawkins in the 1850s. Engineer-turned-paleontologist Louis Dollo will publish the first of several papers on these fossils in 1882.

image From 1879 through 1882, Walther Flemming describes and names CHROMATIN, MITOSIS, and the SPIREME. He makes the first accurate counts of chromosome numbers and accurately drew the "longitudinal splitting" of chromosomes.

1879

image From 1879 through 1882, Walther Flemming describes and names CHROMATIN, MITOSIS, and the SPIREME. He makes the first accurate counts of chromosome numbers and accurately drew the "longitudinal splitting" of chromosomes.

Eight-year-old Maria de Sautuola finds a Paleolithic cave drawing of bison on her father's property in Spain. It is the oldest artwork yet discovered, but it will be dismissed as a forgery for years, considered too beautiful to be the work of prehistoric savages.

Charles Lapworth resolves a priority dispute between Adam Sedgwick and Roderick Murchison by assigning older rocks to the Cambrian (named by Sedgwick), younger rocks to the Silurian (named by Murchison), and naming the Ordivician System in between.

The United States Geological Survey is formed.

image image image Throughout the decade of 1880-1890, Walther Flemming, Eduard Strasburger, Edouard van Beneden, and others elucidate the essential facts of cell division and stressed the importance of the qualitative and quantitative equality of chromosome distribution to daughter cells.

1880

image image image Throughout the decade of 1880-1890, Walther Flemming, Eduard Strasburger, Edouard van Beneden, and others elucidate the essential facts of cell division and stressed the importance of the qualitative and quantitative equality of chromosome distribution to daughter cells.

Charles Darwin and his son Francis publish the results of their studies on plant responses to light, explaining that phototropism (bending toward the light) results from light reaching the top of a plant's shoot.

image Pierre Curie discovers the piezoelectric effect: certain substances produce an electric current when they are physically distorted, and conversely they are physically distorted when an electric current is applied to them. This effect has many applications, including, in the 21st century, the construction of high-end tweeters in stereo systems.

(no entry for this year)

1881

image Hermann Ludwig von Helmholtz shows that the electrical charges in atoms are divided into definite integral portions, suggesting the idea that there is a smallest unit of electricity.

Walther Flemming publishes accurate depictions of cell division (mitosis) in Zellsubstanz, Kern und Zelltheilung.

image Eduard Strasburger coins the terms CYTOPLASM and NUCLEOPLASM.

image W. Flemming discovers lampbrush chromosomes and coins the term MITOSIS.

1882

Walther Flemming publishes accurate depictions of cell division (mitosis) in Zellsubstanz, Kern und Zelltheilung.

image Eduard Strasburger coins the terms CYTOPLASM and NUCLEOPLASM.

image W. Flemming discovers lampbrush chromosomes and coins the term MITOSIS.

Karl Alfred von Zittel describes an exceptionally well-preserved pterosaur wing showing flight membranes in detail.

Charles Darwin publishes his final letter to Nature, on the dispersal of freshwater bivalves. His obituary appears the same month. In this paper, Darwin acknowledges the assistance of W. D. Crick or Northampton. Later, Crick's grandson — Francis Crick — will be one of the co- discoverers of the structure of DNA.

image John William Strutt, Lord Rayleigh, discovers that the ratio of the atomic mass of oxygen to that of hydrogen is not 16 exactly, as had been assumed, but 15.882.

image August Weismann points out the distinction in animals between the somatic cell line and the germ cells, stressing that only changes in germ cells are transmitted to further generations.

image Edouard van Beneden announced the principles of genetic continuity of chromosomes and reported the occurrence of chromosome reduction at germ cell formation. The sperm and egg are haploid and fertilization restores the diploid chromosome number.

image Wilhelm Roux offers a possible explanation for the function of mitosis.

image William Keith Brooks, a professor at The Johns Hopkins University, publishes The Law of Heredity: A Study of the Cause of Variation and the Origin of Living Organisms. Although this speculative work did not significantly advance the understanding of heredity, brooks' thinking is important because during his career he provided instruction to and supervised the early research of Thomas H. Morgan, Edmund Beecher Wilson, and William Bateson — ultimately some of the most important contributors to the new science of genetics.

1883

image August Weismann points out the distinction in animals between the somatic cell line and the germ cells, stressing that only changes in germ cells are transmitted to further generations.

image Edouard van Beneden announced the principles of genetic continuity of chromosomes and reported the occurrence of chromosome reduction at germ cell formation. The sperm and egg are haploid and fertilization restores the diploid chromosome number.

image Wilhelm Roux offers a possible explanation for the function of mitosis.

image William Keith Brooks, a professor at The Johns Hopkins University, publishes The Law of Heredity: A Study of the Cause of Variation and the Origin of Living Organisms. Although this speculative work did not significantly advance the understanding of heredity, brooks' thinking is important because during his career he provided instruction to and supervised the early research of Thomas H. Morgan, Edmund Beecher Wilson, and William Bateson — ultimately some of the most important contributors to the new science of genetics.

image Pierre Émile Duclaux introduces the custom of designating an enzyme by the by the name of the substrate on which its action was first reported and adding the suffix -ase.

Geologist James Hall names Cryptozoon, based on cabbagelike rocks up to meter across. Although Hall's biologic interpretation of these structures will be heavily criticized, it will ultimately prove correct.

image image image image During 1884-88, identification of the cell nucleus as the basis for inheritance was independently reported by Oscar Hertwig, Eduard Strasburger, Albrecht von Kölliker, and August Weismann.

image Gregor Mendel dies on January 6th, without ever knowing that his work on peas would lead to the transformation of biological research.

image image image Walther Flemming, Eduard Strasburger and Edouard van Beneden demonstrate that chromosome doubling occurs by a process of longitudinal splitting. Strasburger describes and names the PROPHASE, METAPHASE, and ANAPHASEstages of chromosomal division.

1884

image image image image During 1884-88, identification of the cell nucleus as the basis for inheritance was independently reported by Oscar Hertwig, Eduard Strasburger, Albrecht von Kölliker, and August Weismann.

image Gregor Mendel dies on January 6th, without ever knowing that his work on peas would lead to the transformation of biological research.

image image image Walther Flemming, Eduard Strasburger and Edouard van Beneden demonstrate that chromosome doubling occurs by a process of longitudinal splitting. Strasburger describes and names the PROPHASE, METAPHASE, and ANAPHASEstages of chromosomal division.

image August Weismann formulates the germ-plasm theory which held that the germ plasm was separate from the somatoplasm and was continuous from generation to generation.

image Carl Rabl theorized the individuality of chromosomes in all stages of the cell cycle.

image Walther Flemming observed sister chromatids passing to opposite poles of the cell during mitosis.

1885

image August Weismann formulates the germ-plasm theory which held that the germ plasm was separate from the somatoplasm and was continuous from generation to generation.

image Carl Rabl theorized the individuality of chromosomes in all stages of the cell cycle.

image Walther Flemming observed sister chromatids passing to opposite poles of the cell during mitosis.

Johann Jakob Balmer discovers the formula for the hydrogen spectrum that will later inspire Niels Bohr to develop his model of the atom.

image Francis Galton devised a new useful statistical tool, the correlation table.

image Hugo de Vries (Holland) discovers aberrant evening primrose plants at Hilversum, Holland. Experiments with these extending over 15 years formed the basis for his mutation theory of evolution.

1886

image Francis Galton devised a new useful statistical tool, the correlation table.

image Hugo de Vries (Holland) discovers aberrant evening primrose plants at Hilversum, Holland. Experiments with these extending over 15 years formed the basis for his mutation theory of evolution.

image A. Ficatier publishes an account of the discovery of a trilobite perforated with two holes (perhaps to hang on a thread) at a Magdalenian- age site in France. The fossil lends the site its name of La Grotte du Trilobite.

John Bell Hatcher develops the "ant hill method of collecting minute fossils," collecting hundreds of tiny fossil teeth and jaws pushed to the surface by ants. He even carries shovelfuls of ants and sediment to other fossil localities in need of excavation by the arthropods.

image William Crookes proposes that atomic weights measured by chemists are averages of the weights of different kinds of atoms of the same element (although it will not be until 1910 that Frederick Soddy identifies these different kinds of atoms as isotopes).

image August Weismann elaborated an all-encompassing theory of chromosome behavior during cell division and fertilization and predicted the occurrence of a reduction division (meiosis) in all sexual organisms.

image Edouard van Beneden demonstrated chromosome reduction in gamete maturation, thereby confirming August Weismann's predictions.

image Wilhelm Roux put forth the suggestion that the linearly arranged qualities of the chromosomes were equally transmitted to both daughter cells at meiosis.

1887

Worthington George Smith excavates a Bronze Age grave of a mother and child, surrounded by at least 200 fossil sea urchins, on Dunstable Downs. He nicknames the mother Maud.

image August Weismann elaborated an all-encompassing theory of chromosome behavior during cell division and fertilization and predicted the occurrence of a reduction division (meiosis) in all sexual organisms.

image Edouard van Beneden demonstrated chromosome reduction in gamete maturation, thereby confirming August Weismann's predictions.

image Wilhelm Roux put forth the suggestion that the linearly arranged qualities of the chromosomes were equally transmitted to both daughter cells at meiosis.

image Harry Govier Seeley determines that dinosaurs consist of "lizard- hipped" (saurischian) and "bird-hipped" (ornithischian) branches.

image image Albert Michelson and Edward Morley measure the velocity of light in two directions, attempting to detect the proper motion of Earth through the ether (a hypothesized fluid that was assumed to fill all space, providing a medium for the transport of electromagnetic waves). The Michelson Morley experiment reveals no evidence of motion.

image Ernst Mach notes that airflow becomes disturbed at the speed of sound.

German anatomist W. von Waldeyer names chromosomes.

image Heinrich Wilhelm Gottfried von Waldeyer names the CHROMOSOME.

image Theodor Boveri verifies August Weismann's predictions of chromosome reduction by direct observation in Ascaris.

1888

German anatomist W. von Waldeyer names chromosomes.

image Heinrich Wilhelm Gottfried von Waldeyer names the CHROMOSOME.

image Theodor Boveri verifies August Weismann's predictions of chromosome reduction by direct observation in Ascaris.

image Heinrich Rudolf Hertz produces and detects radio waves for the first time. Radio waves will be called Hertzian waves until renamed by Marconi, who calls them radiotelegraphy waves.

image Francis Galton publishes Natural Inheritance. In it he describes the quantitative measurement of metric traits in populations. He thus founds biometry and the statistical study of variation. Ultimately, he formulates the Law of Ancestral Inheritance, a statistical description of the relative contributions to heredity made by one's ancestors.

1889

image Francis Galton publishes Natural Inheritance. In it he describes the quantitative measurement of metric traits in populations. He thus founds biometry and the statistical study of variation. Ultimately, he formulates the Law of Ancestral Inheritance, a statistical description of the relative contributions to heredity made by one's ancestors.

image George Francis Fitzgerald formulates the principle that objects shrink slightly in the direction they are traveling, now known as the Fitzgerald-Lorenz contraction, since Hendrik Antoon Lorentz reaches the same conclusion a few years later.

image The numerical equality of paternal and maternal chromosomes at fertilization was established by Theodor Boveri and Jean-Louis-Léon Guignard.

1890

image The numerical equality of paternal and maternal chromosomes at fertilization was established by Theodor Boveri and Jean-Louis-Léon Guignard.

(no entry for this year)

1891

(no entry for this year)

image Publication of August Weismann's book Das Keimplasma (The Germ Plasm) emphasized meiosis as an exact mechanism of chromosome distribution.

1892

image Publication of August Weismann's book Das Keimplasma (The Germ Plasm) emphasized meiosis as an exact mechanism of chromosome distribution.

Joseph Whiteaves describes Anomalocaris, meaning "anomalous shrimp," from the Cambrian. The fossil that Whiteaves identifies as a shrimp will later prove to be part of a much larger animal.

(no entry for this year)

1893

Entomologist E.B. Poulton studies caterpillars from the species Gastropacha quercifolia, noting how siblings look different depending on where they live and what they eat. His discovery will become known as phenotypic plasticity.

image Wilhelm Wien discovers that the maximum wavelength emitted by hot body varies inversely with its absolute temperature. Wien's law becomes useful in establishing the temperature of stars. The problems he has with deriving an equation to describe black-body radiation lead to Max Planck's introduction of the quantum in 1900.

image Hans Driesch expounded the view that all nuclei of an organism were equipotential but varied in their activity in accordance with the differentiation of tissues.

image Karl Pearson published the first in a long series of contributions to the mathematical theory of evolution. Methods for analyzing statistical frequency distributions were developed in detail.

image William Bateson's Materials for the Study of Variation emphasized the importance of discontinuous variations, foreshadowing the rediscovery of Mendel's work.

1894

image Hans Driesch expounded the view that all nuclei of an organism were equipotential but varied in their activity in accordance with the differentiation of tissues.

image Karl Pearson published the first in a long series of contributions to the mathematical theory of evolution. Methods for analyzing statistical frequency distributions were developed in detail.

image William Bateson's Materials for the Study of Variation emphasized the importance of discontinuous variations, foreshadowing the rediscovery of Mendel's work.

Eugène Dubois publishes his monograph of Pithecanthropus erectus, or Java Man, a missing link between humans and apes.

French paleontologist Charles Brongniart describes a fossil dragonfly from the Carboniferous with a 2-foot (63-centimeter) wingspan. The find implies a higher oxygen content in the Earth's ancient atmosphere.

image The intricately carved mammoth ivory figurine known as the Lady (or Venus) of Brassempouy is discovered in France. At roughly 25,000 years old, it ranks among the earliest known depictions of a human face.

image Joseph John (J.J.) Thomson announces that he has found that the velocity of cathode rays is much lower than that of light.

(no entry for this year)

1895

A team of paleontologists, including Samuel Williston, Elmer Riggs and Barnum Brown, successfully excavates a Triceratops fossil in Wyoming.

image Charles Thomson Rees Wilson develops the CLOUD CHAMBER, a box containing a gas that is saturated. When a charged particle passes through the gas, small droplets are formed that make the track of the particle visible. The cloud chamber becomes a powerful tool in particle physics.

image Pierre Curie shows that as the temperature of the magnet is increased, there is a level at which the magnetism is disrupted and ceases to exist. This temperature is still called the Curie point.

image Wilhelm Konrad Röntgen (Roentgen) discovers X-rays, which will soon be applied in the visualization of bodily structures and in the induction of genetic mutations (both intentionally and accidentally).

image E. B. Wilson publishes The Cell in Development and Heredity. This influential treatise (ultimately reprinted in several editions) distills the information compiled concerning cytology in the half-century since Schleiden and Schwann put forth the cell theory.

1896

image E. B. Wilson publishes The Cell in Development and Heredity. This influential treatise (ultimately reprinted in several editions) distills the information compiled concerning cytology in the half-century since Schleiden and Schwann put forth the cell theory.

Dublin anatomist Daniel Cunningham concludes that Neanderthals represent an intermediate step between Pithecanthropus erectus and modern humans.

J. de Morgan describes nine pierced fossil urchins found in a Chalcolithic tomb at Toukh.

image Less than three months after the discovery of x-rays, Dartmouth College Professor of Physics Edwin Frost and his brother, the then physician in chief of Mary Hitchcock Hospital, Gilman Frost, MD, take the first clinical X-ray in the US — an image of Eddie McCarthy's fractured left wrist.

image Antoine-Henri Becquerel discovers rays produced by uranium — the first observation of natural radioactivity.

(no entry for this year)

1897

image Gabriel Bertrand coined the term COENZYME to designate inorganic substances which were necessary to activate certain enzymes.

Renowned physicist Lord Kelvin gives a lecture at London's Victoria Institute claiming that the sun, which is cooling from its initial formation, can be no more than 20 million years old.

image Joseph John Thomson discovers the electron, the first known particle that is smaller than an atom, in part because he has better vacuum pumps that were previously available. He, and independently, Emil Wiechert, determine the ratio of mass to charge of the particles by deflecting them by electric and magnetic fields.

Marie Curie begins research of "uranium rays" that will lead to the discovery of radioactivity.

(no entry for this year)

1898

image image Marie and Pierre Curie discovered that thorium, gives off "uranium rays", which Marie renames RADIOACTIVITY.

image image L. Cuénot (France) working with animals, and Strasburger (Germany) working with plants, advance theory that sex is controlled within the germ cell, not by environment.

Richard Altmann renames "nuclein" as NUCLEIC ACID.

The First International Congress of Genetics held in London.

image William Bateson writes a paper on hybridisation and cross-breeding as a method of scientific investigation that anticipates Mendel's rediscovery.

1899

image British physicist Ernest Rutherford discovers the radioactivity from uranium has at least two different forms, which he calls alpha and beta rays.

image image image Fritz Geisel, Antoine-Henri Becquerel, and Marie Curie proved the beta rays consist of high-speed electrons.

image image L. Cuénot (France) working with animals, and Strasburger (Germany) working with plants, advance theory that sex is controlled within the germ cell, not by environment.

Richard Altmann renames "nuclein" as NUCLEIC ACID.

The First International Congress of Genetics held in London.

image William Bateson writes a paper on hybridisation and cross-breeding as a method of scientific investigation that anticipates Mendel's rediscovery.

1900

image image image H. de Vries, C. Correns, and E. Tschermak independently rediscover Mendel's paper. Using several plant species, de Vries and Correns had performed breeding experiments that paralleled Mendel's earlier studies and had independently arrived at similar interpretations of their results. Therefore, upon reading Mendel's publication they immediately recognized its significance. W. Bateson also stresses the importance of Mendel's contribution in an address to the Royal Society of London.

image K. Landsteiner discovers the blood-agglutination phenomenon in man.

image Karl Pearson develops the chi-square test.

image Paul Karl Ludwig Drude shows that moving electrons conduct electricity in metals.

image Paul Ulrich Villard is the first to observe a radiation that is more penetrating than X-rays, now called gamma rays.

image On December 14, Max Planck announces the first step toward quantum theory. He states that substances can emit light only at certain energies, which implies that some physical processes are not continuous, but occur only in specified amounts called quanta.

image H. de Vries adopts the term MUTATION to describe sudden, spontaneous, drastic alterations in the hereditary material of Oenothera.

T. H. Montgomery studies spermatogenesis in various species of Hemiptera. He concludes that maternal chromosomes only pair with paternal chromosomes during meiosis.

1901

image H. de Vries adopts the term MUTATION to describe sudden, spontaneous, drastic alterations in the hereditary material of Oenothera.

T. H. Montgomery studies spermatogenesis in various species of Hemiptera. He concludes that maternal chromosomes only pair with paternal chromosomes during meiosis.

image Harry Govier Seeley publishes Dragons of the Air, the first popular book on pterosaurs, arguing that they were warm-blooded and should be classified parallel to birds, in between reptiles and mammals. This is in direct opposition to Richard Owen's classification of pterosaurs as cold-blooded and poor flyers.

image Archibald Garrod, a British physician, reports that alkaptonuria (a human disease) seems to be inherited as a Mendelian recessive.

image C. E. McClung argues that particular chromosomes determine the sex of the individual carrying them, not just in insects, but perhaps in other species (including man).

image Walter Sutton concludes that (a) chromosomes have individuality, (b) that they occur in pairs, with one member of each pair contributed by each parent, and (c) that the paired chromosomes separate from each other during meiosis.

image T. Boveri studies sea urchin embryos and finds that in order to develop normally, the organism must have a full set of chromosomes, and from this he concludes that the individual chromosomes must carry different essential hereditary determinants.

image William Bateson coins terms that will become essential to describing findings in the new science of heredity: GENETICS, F1, F2, ALLELOMORPH (later shortened to ALLELE), HOMOZYGOTE, HETEROZYGOTE, and EPISTASIS.

1902

image Archibald Garrod, a British physician, reports that alkaptonuria (a human disease) seems to be inherited as a Mendelian recessive.

image C. E. McClung argues that particular chromosomes determine the sex of the individual carrying them, not just in insects, but perhaps in other species (including man).

image Walter Sutton concludes that (a) chromosomes have individuality, (b) that they occur in pairs, with one member of each pair contributed by each parent, and (c) that the paired chromosomes separate from each other during meiosis.

image T. Boveri studies sea urchin embryos and finds that in order to develop normally, the organism must have a full set of chromosomes, and from this he concludes that the individual chromosomes must carry different essential hereditary determinants.

image William Bateson coins terms that will become essential to describing findings in the new science of heredity: GENETICS, F1, F2, ALLELOMORPH (later shortened to ALLELE), HOMOZYGOTE, HETEROZYGOTE, and EPISTASIS.

Barnum Brown of the American Museum of Natural History discovers Tyrannosaurus rex.

image The concepts of PHENOTYPE, GENOTYPE, and SELECTION were introduced and clearly defined by Wilhelm Ludwig Johannsen.

1903

image Cheddar Man, a human male fossil, is discovered at Gough's Cave in Cheddar Gorge, England. Sometimes referred to as the earliest Englishman, Cheddar Man turns out to be only about 15,000 years old. it appears that he died a violent death. A large crater-like lesion just above the skull's right orbit suggests that the man may have also been suffering from a bone infection at the time. It is Britain’s oldest complete human skeleton.

image The concepts of PHENOTYPE, GENOTYPE, and SELECTION were introduced and clearly defined by Wilhelm Ludwig Johannsen.

L. de Vesly describes first- to third-century remains at Gallo Roman temples and wells near Rouen, France. Finds there include a cache of Neolithic axes and fossil sea urchins — evidence of association of axes and urchins over thousands of years.

image Carl Neuberg first used the term BIOCHEMISTRY.

Physicist Ernest Rutherford lectures the British Association that radioactivity could power the sun and maintain its heat, meaning the sun and Earth could be much older than Lord Kelvin's estimate.

(no entry for this year)

1904

image Entomologist George Willis Kirkaldy publishes species descriptions of a series of insects whose names all end in "-chisme" (pronounced "kiss me"), such as Ohchisme, Dolichisme, Elachisme, Florichisme, Isachisme, Marichisme, Nanichisme, Peggichisme, and Polychisme. Kirkaldy's proposed names preface -chisme with the names of various women from alleged romantic conquests. In 1912 a letter to the International Entomological Congress from Lord Walsingham sought to make these names invalid on the basis of their being non-classical in their derivation. Kirkaldy himself had been a firm adherent to the principle of priority and was against any form of orthographic emendation to the spelling proposed by the original authors.

K. S. Merezhkovsky suggests that chloroplasts originated as a cyanobacterium swallowed by a protozoan, i.e., algal and plant cells result from two independent organisms that became symbionts. The idea will be largely forgotten until it is suggested again in the 1960s.

image Lucien Claude Cuénot performs crosses between mice carrying a gene that gives them yellow fur. Since they always produce yellow furred and agouti offspring in a 2:1 ratio, he concludes they are heterozygous. (In 1910, W. E. Castle and C. C. Little will show that yellow homozygotes die in utero. This dominant allele is thus the first gene shown to behave as a homozygous lethal.)

1905

K. S. Merezhkovsky suggests that chloroplasts originated as a cyanobacterium swallowed by a protozoan, i.e., algal and plant cells result from two independent organisms that became symbionts. The idea will be largely forgotten until it is suggested again in the 1960s.

image Lucien Claude Cuénot performs crosses between mice carrying a gene that gives them yellow fur. Since they always produce yellow furred and agouti offspring in a 2:1 ratio, he concludes they are heterozygous. (In 1910, W. E. Castle and C. C. Little will show that yellow homozygotes die in utero. This dominant allele is thus the first gene shown to behave as a homozygous lethal.)

image The Swimming Reindeer — the largest ivory carving from the late Ice Age yet found — is pieced together by Abbé Henri Breuil from two reindeer carved from mammoth ivory found decades earlier by Peccadeau de l'Isle.

Albert Einstein proposes the special theory of relativity (E=mc2).

image image William Bateson and Reginald Crundall Punnett report the discovery of two new genetic principles: LINKAGE and GENE INTERACTION.

1906

image image William Bateson and Reginald Crundall Punnett report the discovery of two new genetic principles: LINKAGE and GENE INTERACTION.

In his presidential address to the Geological Society of America, Raphael Pumpelly claims that the end of the Pleistocene started the Neolithic Revolution.

(no entry for this year)

1907

Chemist Bertram Boltwood measures the ratio of isotopes of uranium and lead in a mineral from Connecticut. He concludes the mineral formed 410 million years ago. His estimate will later be changed to 265 million, but this experiment lays the groundwork for radiometric dating techniques.

P. Raymond describes a Neolithic deposit in Saône-et-Loire in France containing an axe with three fossil sea urchins.

image The Mauer jaw is discovered in Germany. On October 21, 1907, Daniel Hartmann, a worker at a sand mine in the Grafenrain open field system of the Mauer community unearthed a mandible at a depth of 24.63 m (80.81 ft), which he recognized as of human origin.[4] He was aware of the likelihood of finds, as for 20 years the Heidelberg scholar Otto Schoetensack had asked that the workers at the sand mine be encouraged to look out for fossils, after the well-preserved skull of a straight-tusked elephant had come to light there in 1887. Schoetensack had the workers taught the characteristics of human bones based on recent examples on his regular visits to the sand mine in search for "traces of mankind". The mandible will become the type specimen for Homo heidelbergensis (Archaic Homo sapiens, precursors to Neanderthals).

image Godfrey Harold Hardy, a Cambridge mathematician, writes a letter to the editor of Science, suggesting that Mendelian mechanisms acting alone have no effect on allele frequencies. The letter begins, I am reluctant to intrude in a discussion concerning matters of which I have no expert knowledge, and I should have expected the very simple point which I wish to make to have been familiar to biologists. However,... This short (less than one page) letter constitutes Hardy's entire lifetime contribution to the field of biology, yet still forms the mathematical basis for population genetics.

1908

image Godfrey Harold Hardy, a Cambridge mathematician, writes a letter to the editor of Science, suggesting that Mendelian mechanisms acting alone have no effect on allele frequencies. The letter begins, I am reluctant to intrude in a discussion concerning matters of which I have no expert knowledge, and I should have expected the very simple point which I wish to make to have been familiar to biologists. However,... This short (less than one page) letter constitutes Hardy's entire lifetime contribution to the field of biology, yet still forms the mathematical basis for population genetics.

Amadee and Jean Bouyssonie find a Neanderthal skeleton in a pit at La Chapelle-aux-Saints. The find spurs hypotheses of intentional Neanderthal burial of the dead, although some anthropologists will dispute this interpretation several decades later.

Charles and George Sternberg discover a dinosaur mummy, a duckbill dinosaur with skin, tendons and bits of flesh all fossilized.

image T. H. Morgan, later to become the first recipient of the Nobel Prize for work in genetics, writes a paper expressing doubts about the profusion of Mendelian explanations for inherited properties.

image A. E. Garrod publishes Inborn Errors of Metabolism, the earliest discussion of the biochemical genetics of man (or any other species).

image George H. Shull advocates the use of self-fertilized lines in production of commercial seed corn. The hybrid corn program that resulted, created an abundance of foodstuffs worth billions of dollars.

H. Nilsson Ehle puts forward the multiple-factor hypothesis to explain the quantitative inheritance of seed-coat color in wheat.

image W. Johannsen's studies of the inheritance of seed size in self-fertilized lines of beans leads him to realize the necessity of distinguishing between the appearance of an organism and its genetic constitution. He invents the terms PHENOTYOPE and GENOTYPE to serve this purpose, and he also coins the word GENE.

1909

image T. H. Morgan, later to become the first recipient of the Nobel Prize for work in genetics, writes a paper expressing doubts about the profusion of Mendelian explanations for inherited properties.

image A. E. Garrod publishes Inborn Errors of Metabolism, the earliest discussion of the biochemical genetics of man (or any other species).

image George H. Shull advocates the use of self-fertilized lines in production of commercial seed corn. The hybrid corn program that resulted, created an abundance of foodstuffs worth billions of dollars.

H. Nilsson Ehle puts forward the multiple-factor hypothesis to explain the quantitative inheritance of seed-coat color in wheat.

image W. Johannsen's studies of the inheritance of seed size in self-fertilized lines of beans leads him to realize the necessity of distinguishing between the appearance of an organism and its genetic constitution. He invents the terms PHENOTYOPE and GENOTYPE to serve this purpose, and he also coins the word GENE.

Abbé Breuil depicts a presumed Neanderthal burial at La Ferrassie.

Arthur Smith Woodward lectures the British Association for the Advancement of Science on "excess growth" and tooth loss in dinosaurs, citing these things as evidence of "racial senility" that doomed the dinosaurs to extinction.

Charles Doolittle Walcott starts digging fossils of soft-bodied animals in the Burgess Shale in the Canadian Rockies. He proceeds to publish several papers in which he describes these animals, which lived over 500 million years ago, as primitive ancestors of modern groups.

1910

image T. H. Morgan discovers white eye and consequently sex linkage in Drosophila. Drosophila genetics begins.

image A few years after the find of some isolated teeth from the same species, British paleontologist Clive Forster Cooper finds better specimens of what will later be identified as Paraceratherium in an area that will later be part of Pakistan. A century later, Paraceratherium will still hold the title of the biggest land mammal yet discovered.

While digging the foundation for an imposing home, two laborers, Mercer and Crittenden, discover the remains of a cremation from the Iron Age, including a Neolithic axe and a fossil echinoid.

1911

image A chance discovery turns up the astonishingly well-preserved Clacton Spear. Made of yew and over 400,000 years old, it's one of the world's oldest wooden artifacts.

image T. H. Morgan proposes that the genes for white eyes, yellow body, and miniature wings in Drosophila are linked together on the X chromosome.

image A hand axe, possibly 200,000 years old and of Neanderthal design, is found in Norfolk, England. The axe has been fashioned to give prominence to a fossil bivalve.

Charles Dawson discovers the Piltdown skull in southern England. Excavations of faked fossils will continue for years.

(no entry for this year)

1912

Alfred Wegener proposes the theory of continental drift. His ideas will be almost completely ignored until the late 1960s.

image A. H. Sturtevant, an undergraduate working with Morgan at Columbia, provides the experimental basis for the linkage concept in Drosophila and produces the first GENETIC MAP.

1913

image A. H. Sturtevant, an undergraduate working with Morgan at Columbia, provides the experimental basis for the linkage concept in Drosophila and produces the first GENETIC MAP.

Geologist-physicist Arthur Holmes concludes that the breakdown of radioactive isotopes in igneous rocks can be used to determine when the rocks solidified. The ability to determine the absolute ages of rocks will enable scientists to better date fossils.

1914

image Calvin Blackman Bridges reports nondisjunction of sex chromosomes as PROOF of the chromosome theory of heredity.

Charles Doolittle Walcott identifies fossil bacteria in Cryptozoon-like structures (stromatolites).

Peyrony finds the remains of Neanderthal baby in southwestern France. Because no one knows the bones are Neanderthal, they are not examined closely and are later believed lost. They will be rediscovered and described nearly 90 years later.

image Calvin Bridges identifies strains of mutant fruit flies with extra pairs of wings. Decades later, these strains will help biologists understand Hox genes that control the head-to-toe anatomy of widely varying animals.

image Frederick Twort discovers a virus capable of infecting and destroying bacteria.

image image image image Thomas Hunt Morgan, Alfred Henry Sturtevant, Calvin Blackman Bridges, and Hermann Joseph Muller publish The Mechanism of Mendelian Heredity. This monograph provides the first systematic description of the actual mechanisms that control inheritance as evidenced in the Mendelian model. Here, for the first time, the gene is made real.

1915

image Calvin Bridges identifies strains of mutant fruit flies with extra pairs of wings. Decades later, these strains will help biologists understand Hox genes that control the head-to-toe anatomy of widely varying animals.

image Frederick Twort discovers a virus capable of infecting and destroying bacteria.

image image image image Thomas Hunt Morgan, Alfred Henry Sturtevant, Calvin Blackman Bridges, and Hermann Joseph Muller publish The Mechanism of Mendelian Heredity. This monograph provides the first systematic description of the actual mechanisms that control inheritance as evidenced in the Mendelian model. Here, for the first time, the gene is made real.

(no entry for this year)

1916

Two duckbill dinosaur fossils, with extremely rare skin impressions, sink to the bottom of the Atlantic when the ship carrying them to London — the SS Mount Temple — is stopped by the German military vessel, the SMS Möwe. The German ship takes the passengers prisoner and then sinks the Mount Temple.

image British polymath D'Arcy Wentworth Thompson publishes On Growth and Form arguing that the forms Darwinian natural selection can produce through evolution are constrained by physical and mathematical laws, and that organic structures often emulate inorganic natural structures. His analysis led the way for the scientific explanation of morphogenesis, the process by which patterns and body structures are formed in plants and animals. Thompson's description of the mathematical beauty of nature and the mathematical basis of the forms of animals stimulated thinkers as diverse as Julian Huxley, Conrad Hal Waddington, Alan Turing, Claude LTvi-Strauss, Eduardo Paolozzi, Le Corbusier, and Mies van der Rohe.

image C. B. Bridges discovers the first chromosome deficiency in Drosophila.

image Felix Hubert D'Herelle, independently of Frederick Twort, discovers a virus capable of infecting and destroying bacteria, which he calls a BACTERIOPHAGE.

1917

Stone tools discovered at Bir el Ater in eastern Algeria include triangular objects that might have been arrowheads or spear points. The tools will be dubbed Aterian, but their age will be underestimated for decades.

image British polymath D'Arcy Wentworth Thompson publishes On Growth and Form arguing that the forms Darwinian natural selection can produce through evolution are constrained by physical and mathematical laws, and that organic structures often emulate inorganic natural structures. His analysis led the way for the scientific explanation of morphogenesis, the process by which patterns and body structures are formed in plants and animals. Thompson's description of the mathematical beauty of nature and the mathematical basis of the forms of animals stimulated thinkers as diverse as Julian Huxley, Conrad Hal Waddington, Alan Turing, Claude LTvi-Strauss, Eduardo Paolozzi, Le Corbusier, and Mies van der Rohe.

image C. B. Bridges discovers the first chromosome deficiency in Drosophila.

image Felix Hubert D'Herelle, independently of Frederick Twort, discovers a virus capable of infecting and destroying bacteria, which he calls a BACTERIOPHAGE.

(no entry for this year)

1918

(no entry for this year)

image Thomas Hunt Morgan and coworkers publish The Physical Basis of Heredity, a book-length summary of the rapidly growing findings in genetics.

image C. B. Bridges discovers chromosomal duplications in Drosophila.

image T. H. Morgan calls attention to the equality in Drosophila melanogaster between the number of linkage groups and the haploid number of chromosomes.

1919

image Thomas Hunt Morgan and coworkers publish The Physical Basis of Heredity, a book-length summary of the rapidly growing findings in genetics.

image C. B. Bridges discovers chromosomal duplications in Drosophila.

image T. H. Morgan calls attention to the equality in Drosophila melanogaster between the number of linkage groups and the haploid number of chromosomes.

Swedish geologist Johann Andersson discovers a major "dragon bone works" in northern China. Otto Zdansky also examines the works several years later, discovering that the fossils are referred to as dragons even though the workers recognize them as more pedestrian species such as horses and deer.

(no entry for this year)

1920

(no entry for this year)

(no entry for this year)

1921

Fossil mammal expert William Diller Matthew suggests dinosaurs were driven extinct by mountain building, continental uplift and replacement by mammals.

Miners at Broken Hill in the British colony of Northern Rhodesia, Africa, find leg bones and a skull that will later be classified as Homo heidelbergensis.

Lillian V. Morgan discovers attached-X chromosomes in Drosophila.

1922

Lillian V. Morgan discovers attached-X chromosomes in Drosophila.

The American Museum of Natural History begins a series of excavations in central Mongolia, led by Roy Chapman Andrews. Hoping to find fossil human remains, Chapman's team instead finds dinosaurs.

A. E. Boycott and C. Diver describe "delayed" Mendelian inheritance controlling the direction of the coiling of the shell in the snail Limnea peregra. A. H. Sturtevant suggests that the direction of coiling of the Limnea shell is determined by the character of the ooplasm, which is in turn controlled by the mother's genotype.

image C. B. Bridges discovers chromosomal translocations in Drosophila.

1923

A. E. Boycott and C. Diver describe "delayed" Mendelian inheritance controlling the direction of the coiling of the shell in the snail Limnea peregra. A. H. Sturtevant suggests that the direction of coiling of the Limnea shell is determined by the character of the ooplasm, which is in turn controlled by the mother's genotype.

image C. B. Bridges discovers chromosomal translocations in Drosophila.

Jesuit priests Émile Lincent and Pierre Teilhard de Chardin discover ancient stone tools at Shuidonggou, China. Their discoveries resemble those of the Middle Paleolithic industry in Europe.

(no entry for this year)

1924

Winifred Goldring publishes a description of a fossil forest discovered during excavations for the Gilboa Dam. Dating from the Devonian Period, the site will become known as the world's oldest fossil forest.

Tennessee schoolteacher John Thomas Scopes is tried for teaching evolution in the famous "Scopes Monkey Trial." Two-time presidential candidate William Jennings Bryan leads the prosecution. Labor lawyer Clarence Darrow leads the defense and goads Bryan into declaring that humans are not mammals. The conviction will be overturned on a technicality, and the anti- evolution law will remain on the books for decades.

image A. H. Sturtevant analyzes the Bar-eye phenomenon in Drosophila and discovers position effect.

1925

Tennessee schoolteacher John Thomas Scopes is tried for teaching evolution in the famous "Scopes Monkey Trial." Two-time presidential candidate William Jennings Bryan leads the prosecution. Labor lawyer Clarence Darrow leads the defense and goads Bryan into declaring that humans are not mammals. The conviction will be overturned on a technicality, and the anti- evolution law will remain on the books for decades.

image A. H. Sturtevant analyzes the Bar-eye phenomenon in Drosophila and discovers position effect.

Francis Turville-Petre finds Galilee Man, the first fossil hominid discovered in Western Asia. The fossil will later be dated to more than 250,000 years old, and classified as neither modern Homo sapiens nor Neanderthal.

Raymond Dart publishes a description of the "Taung Child," a hominid child's skull from Africa. He classifies it as Australopithecus africanus and concludes that it's the missing link between humans and apes.

A. H. Sturtevant finds the first inversion in Drosophila.

1926

A. H. Sturtevant finds the first inversion in Drosophila.

Harvard geology professor William Morris Davis publishes a paper entitled The Value of Outrageous Geological Hypotheses warning against quick dismissal of new ideas. The paper will become famous.

image Bernard O. Dodge initiates genetic studies on Neurospora.

image H. J. Muller reports the artificial induction of mutations in Drosophila by x-rays.

image J. B. S. Haldane suggests that the genes known to control certain coat colors in various rodents and carnivores may be evolutionarily homologous.

1927

image Bernard O. Dodge initiates genetic studies on Neurospora.

image H. J. Muller reports the artificial induction of mutations in Drosophila by x-rays.

image J. B. S. Haldane suggests that the genes known to control certain coat colors in various rodents and carnivores may be evolutionarily homologous.

Excavations in Kent's Cavern in southern England turn up a fragment of a human upper jaw, roughly 43,000 years old. Arthur Keith will provisionally identify it as anatomically modern human, and this finding will be confirmed in a 2011 study.

Johns Hopkins University biologist Raymond Pearl publishes an article entitled "Why Lazy People Live the Longest." He will expand on this rate- of-living hypothesis in a book the next year, arguing that a faster rate of biochemical reactions leads to a shorter lifespan. This hypothesis is quickly dismissed and generally considered buncombe. Later, however, Donald Trump, the 45th president of the United States will be discovered to hold similar views.

image Frederick Griffith discovers type-transformation of pneumococci. This lays the foundation for the work of Avery, MacLeod, and McCarthy (1944).

image L. J. Stadler reports the artificial induction of mutations in maize, and demonstrates that the dose-frequency curve is linear.

1928

image Frederick Griffith discovers type-transformation of pneumococci. This lays the foundation for the work of Avery, MacLeod, and McCarthy (1944).

image L. J. Stadler reports the artificial induction of mutations in maize, and demonstrates that the dose-frequency curve is linear.

In a letter to Science, Louise Sudbury states that fossil plants, Cycadeoidea Etrusca, were collected by Etruscans over 4,000 years ago.

In trying to piece together a Burgess Shale organism over 500 million years old, Danish zoologist K. L. Henriksen glues an Anomalocaris appendage to a Tuzoia carapace to make what he thinks is a reasonable looking shrimp-like animal. This mistaken interpretation will persist for years.

John Henry Pull, a postman and amateur archaeologist, finds fossil urchins in two separate Neolithic burial sites. His efforts to publish on his findings, however, will be thwarted due to his pedestrian background.

(no entry for this year)

1929

Davidson Black announces the find of Sinanthropus pekinensis, or Peking Man, discovered at Zhoukoudian, China. Over the next several years, five nearly-complete skulls will be recovered from the same site. Peking Man will be lost, however, during World War II.

Estonian paleobiologist Alexander Audova publishes a paper rejecting racial senility as the cause of dinosaur extinction and instead pointing to environmental change.

image R. A. Fisher publishes Genetical Theory of Natural Selection, a formal analysis of the mathematics of selection.

1930

image R. A. Fisher publishes Genetical Theory of Natural Selection, a formal analysis of the mathematics of selection.

Themistocles Zammit publishes Prehistoric Malta: The Tarxien Temples about excavations showing fossil sea urchins in Bronze Age temples.

C. Stern, and independently H. B. Creighton and B. McClintock, provide the cytological proof of crossing over.

1931

C. Stern, and independently H. B. Creighton and B. McClintock, provide the cytological proof of crossing over.

The highly influential paleobotanist Sir Albert Charles Seward rejects the biologic interpretation of Cryptozoon fossils (stromatolites). This rejection will become known among paleontologists as "Seward's folly."

(no entry for this year)

1932

image A Harvard expedition to Australia collects Kronosaurus queenslandicus, a 135-million-year-old marine reptile fossil with a 9- foot skull and banana-sized teeth. Researchers excavate the fossil from a limestone quarry with the aid of explosives.

Fossil diggers discover a 25-million-year-old toothed, dwarf whale in Australia. Seven years later it will be named Mammalodon. More than 70 years later, it will be described as a "bottom-feeding mud-sucker."

Robert Broom publishes The Coming of Man: Was it Accident or Design? arguing that evolution is really driven by spiritual agencies, some with conflicting priorities, and that mankind is the ultimate aim of all evolution.

image T. H. Morgan receives a Nobel Prize in Medicine for his development of the theory of the gene. He is the first geneticist to receive this award.

image Barbara McClintock demonstrates in maize that a single exchange within the inversion loop of a paracentric inversion heterozygote generates an acentric and a dicentric chromatid.

T. S. Painter initiates cytogenetic studies on the salivary gland chromosomes of Drosophila.

1933

Robert Broom publishes The Coming of Man: Was it Accident or Design? arguing that evolution is really driven by spiritual agencies, some with conflicting priorities, and that mankind is the ultimate aim of all evolution.

image T. H. Morgan receives a Nobel Prize in Medicine for his development of the theory of the gene. He is the first geneticist to receive this award.

image Barbara McClintock demonstrates in maize that a single exchange within the inversion loop of a paracentric inversion heterozygote generates an acentric and a dicentric chromatid.

T. S. Painter initiates cytogenetic studies on the salivary gland chromosomes of Drosophila.

(no entry for this year)

1934

With funding from Sinclair Oil, Barnum Brown begins excavating in Wyoming's Howe Quarry. His finds will lead to the green dinosaur logo for Sinclair's gas stations. Many of them will simply be named "Dino."

image C. B. Bridges publishes the salivary gland chromosome maps for Drosophila melanogaster.

G. W. Beadle and B. Ephrussi and A. Kuhn and A. Butenandt work out the biochemical genetics of eye-pigment synthesis in Drosophila and Ephestia, respectively.

image J. B. S. Haldane is the first to calculate the spontaneous mutation frequency of a human gene.

1935

image C. B. Bridges publishes the salivary gland chromosome maps for Drosophila melanogaster.

G. W. Beadle and B. Ephrussi and A. Kuhn and A. Butenandt work out the biochemical genetics of eye-pigment synthesis in Drosophila and Ephestia, respectively.

image J. B. S. Haldane is the first to calculate the spontaneous mutation frequency of a human gene.

M. Baudouin describes more than 80 fossil sea urchins drilled for use as jewelry, some worked as long as 35,000 years ago.

A. H. Sturtevant and T. Dobzhansky publish the first account of the use of inversions in constructing a chromosomal phylogenetic tree.

1936

A. H. Sturtevant and T. Dobzhansky publish the first account of the use of inversions in constructing a chromosomal phylogenetic tree.

Robert Broom finds the first skull of an adult australopithecine near Johannesburg.

T. Dobzhansky publishes Genetics and the Origin of Species — a milestone in evolutionary genetics.

1937

T. Dobzhansky publishes Genetics and the Origin of Species — a milestone in evolutionary genetics.

(no entry for this year)

1938

image Fishermen find a coelacanth, a fish long believed to be extinct, off the coast of South Africa. Margaret Courtney-Latimer, a curator at the East London Museum in South Africa, keeps the fish preserved long enough for its identity to be confirmed by ichthyologist J.L.B. Smith.

E. L. Ellis and M. Delbrück perform studies on coliphage growth that mark the beginning of modem phage work. They devise the "one-step growth" experiment, which demonstrates that after the phage adsorbs onto the bacterium, it replicates within the bacterium during the "latent period," and finally the progeny are released in a "burst."

1939

E. L. Ellis and M. Delbrück perform studies on coliphage growth that mark the beginning of modem phage work. They devise the "one-step growth" experiment, which demonstrates that after the phage adsorbs onto the bacterium, it replicates within the bacterium during the "latent period," and finally the progeny are released in a "burst."

About 200 worked ivory fragments, roughly 32,000 years old, are found in the Hohlenstein-Stadel Cave in Germany. Three decades later, the pieces will be reassembled as statue of a lion-headed man.

(no entry for this year)

1940

Frank Morton Carpenter collects a 2.5-foot wing from a dragonfly-like giant insect that lived in Oklahoma during the Permian Period.

G. W. Beadle and E. L. Tatum publish their classic study on the biochemical genetics of Neurospora and promulgate the ONE-GENE, ONE-ENZYME theory.

K. Mather coins the term polygenes and describes polygenic traits in various organisms.

1941

G. W. Beadle and E. L. Tatum publish their classic study on the biochemical genetics of Neurospora and promulgate the ONE-GENE, ONE-ENZYME theory.

K. Mather coins the term polygenes and describes polygenic traits in various organisms.

Anthropologist E. T. Hall excavates the ruins of a dwelling in New Mexico occupied between 700 and 900 AD. He finds two fossil jawbones of Eocene mammals that were deliberately carried to the dwelling by Paleo- Indians.

German paleontologist H. Kirchner suggests that dinosaur tracks in the Rhine Valley might have inspired the legend of Siegfried slaying the dragon Fafnir.

Ernst Mayr publishes Systematics and the Origin of Species, and Julian Huxley publishes Evolution: The Modern Synthesis. Both books are significant contributions to the neo darwinian synthesis combining elements of natural selection, genetics, mutation, population biology and paleontology.

S. E. Luria and T. F. Anderson publish the first electron micrographs of bacterial viruses. T2 has a polyhedral body and a tail.

1942

Ernst Mayr publishes Systematics and the Origin of Species, and Julian Huxley publishes Evolution: The Modern Synthesis. Both books are significant contributions to the neo darwinian synthesis combining elements of natural selection, genetics, mutation, population biology and paleontology.

S. E. Luria and T. F. Anderson publish the first electron micrographs of bacterial viruses. T2 has a polyhedral body and a tail.

Theoretical physicist Erwin Schrödinger publishes What is Life? arguing that living organisms store and pass along information, perhaps using something like Morse code. This book will inspire James Watson, Francis Crick and Maurice Wilkins, who will share the Nobel prize for discovering the structure of DNA.

O. T. Avery, C. M. MacLeod, and M. McCarty describe the pneumococcus transforming principle. The fact that it is rich in DNA suggests that DNA and not protein is the hereditary chemical.

1944

Theoretical physicist Erwin Schrödinger publishes What is Life? arguing that living organisms store and pass along information, perhaps using something like Morse code. This book will inspire James Watson, Francis Crick and Maurice Wilkins, who will share the Nobel prize for discovering the structure of DNA.

O. T. Avery, C. M. MacLeod, and M. McCarty describe the pneumococcus transforming principle. The fact that it is rich in DNA suggests that DNA and not protein is the hereditary chemical.

image S. E. Luria demonstrates that mutations occur in bacterial viruses.

1945

image S. E. Luria demonstrates that mutations occur in bacterial viruses.

1946

James B. Sumner, John H. Northrop, and Wendell M. Stanley share a Nobel Prize in Chemistry for Sumner's discovery that enzymes can be crystallized and for Northrop and Stanley's preparation of enzymes and virus proteins in a pure form.

image Nobel Prize in Medicine awarded to H. J. Muller for his contributions to radiation genetics

Genetic recombination in bacteriophage is demonstrated by M. Delbrück and W. T. Bailey and by A. D. Hershey.

J. Lederberg and E. L. Tatum demonstrate genetic recombination in bacteria.

Along the Kolyma River in northeastern Siberia, Gulag prisoners discover a nest with three frozen, mummified ground squirrel carcasses. They turn the carcasses over to the Gulag camp geologist, Yuriy Popov, who relays them to other Soviet scientists. Seventy years later, radiocarbon dating and DNA analysis of the ground squirrel mummies will identify their age at over 30,000 years old, and indicate that they are not direct ancestors of modern ground squirrels in the region.

Geologist Reg Sprigg discovers fossils near the Ediacara Hills in Australia. The fossils are of multicellular organisms that predated the Cambrian Period, making them the oldest complex fossils yet discovered. At least some of the fossils are generally assumed to be related to modern cnidarians like jellyfish and corals.

(no entry for this year)

1947

American Museum of Natural History curator Edwin Colbert finds a massive quarry of Coelophysis dinosaurs in New Mexico and concludes from their skeletons that these Triassic dinosaurs were swift runners with a bird- like posture. Later examination of two fossils will lead Colbert to conclude they were also cannibals, but the "last meals of juvenile coelophyses" will eventually prove to be crocodilian.

Rudolph Zallinger completes The Age of Reptiles mural in the Yale Peabody Museum. His image of slow-moving dinosaurs will prevail until the 1960s.

image H. J. Muller coins the term dosage compensation.

J. Lederberg and N. Zinder, and, independently, B. D. Davis develop the penicillin selection technique for isolating biochemically deficient bacterial mutants.

1948

image H. J. Muller coins the term dosage compensation.

J. Lederberg and N. Zinder, and, independently, B. D. Davis develop the penicillin selection technique for isolating biochemically deficient bacterial mutants.

Mary Leakey finds the skull of the ape Proconsul, about 16 million years old. Although a very significant find, it does little to bolster Louis and Mary Leakey's meager research funding.

A. D. Hershey and R. Rotman demonstrate that genetic recombination occurs in bacteriophage.

J. V. Neel provides genetic evidence that the sickle-cell disease is inherited as a simple Mendelian autosomal recessive.

1949

A. D. Hershey and R. Rotman demonstrate that genetic recombination occurs in bacteriophage.

J. V. Neel provides genetic evidence that the sickle-cell disease is inherited as a simple Mendelian autosomal recessive.

French prehistorian André Leroi-Gourhan discovers the Cave of the Reindeer near the village of Arcy-sur-Cure where he will conduct a 15-year excavation. Discoveries at Arcy will suggest to some researchers an artistic sense among Neanderthals, including the collection of fossil mollusk shells and fossil coral. Doubts about ages of objects, however, will leave the subject open to debate.

At a Cold Spring Harbor Symposium, Ernst Mayr argues that all hominid specimens so far found should be categorized in the genus Homo: H. transvaalensis, H. erectus, and H. sapiens.

E. Chargaff lays the foundations for nucleic acid structural studies by his analytical work. He demonstrates for DNA that the numbers of adenine and thymine groups are always equal and so are the numbers of guanine and cytosine groups. These findings later suggest to Watson and Crick that DNA consists of two polynucleotide strands joined by hydrogen bonding between A and T and between G and C.

E. M. Lederberg discovers lambda, the first viral episome of E. coli.

1950

At a Cold Spring Harbor Symposium, Ernst Mayr argues that all hominid specimens so far found should be categorized in the genus Homo: H. transvaalensis, H. erectus, and H. sapiens.

E. Chargaff lays the foundations for nucleic acid structural studies by his analytical work. He demonstrates for DNA that the numbers of adenine and thymine groups are always equal and so are the numbers of guanine and cytosine groups. These findings later suggest to Watson and Crick that DNA consists of two polynucleotide strands joined by hydrogen bonding between A and T and between G and C.

E. M. Lederberg discovers lambda, the first viral episome of E. coli.

Barbara McClintock publishes a paper describing "jumping" genes that can move around within an organism's genome.

1951

Barbara McClintock publishes a paper describing "jumping" genes that can move around within an organism's genome.

A. D. Hershey and M. Chase demonstrate that the DNA of phage enters the host, whereas most of the protein remains behind.

F. Sanger and his colleagues work out the complete amino acid sequence for the protein hormone insulin, and show that it contains two polypeptide chains held together by disulfide bridges.

J. Lederberg and E. M. Lederberg invent the replica plating technique.

N. D. Zinder and J. Lederberg describe transduction in Salmonella.

1952

A. D. Hershey and M. Chase demonstrate that the DNA of phage enters the host, whereas most of the protein remains behind.

F. Sanger and his colleagues work out the complete amino acid sequence for the protein hormone insulin, and show that it contains two polypeptide chains held together by disulfide bridges.

J. Lederberg and E. M. Lederberg invent the replica plating technique.

N. D. Zinder and J. Lederberg describe transduction in Salmonella.

Russian geologist Boris Sokolov establishes the term Vendian. Based on rock strata in the Soviet Union, it designates the period immediately preceding the Cambrian, coinciding with fossils found near the Ediacara Hills.

image image J. D. Watson and F. H. C. Crick propose a model for DNA comprised of two helically intertwined chains tied together by hydrogen bonds between the purines and pyrimidines.

W. Hayes discovers polarized behavior in bacterial recombinations. He isolates the Hfr H strain of E. coli and shows that certain genes are readily transferred from Hfr to F- bacteria, whereas others are not.

1953

image image J. D. Watson and F. H. C. Crick propose a model for DNA comprised of two helically intertwined chains tied together by hydrogen bonds between the purines and pyrimidines.

W. Hayes discovers polarized behavior in bacterial recombinations. He isolates the Hfr H strain of E. coli and shows that certain genes are readily transferred from Hfr to F- bacteria, whereas others are not.

Piltdown Man is determined to be a hoax: the jaw of an ape and a human skull.

Fiesel Houtermans and Clair Patterson publish independent estimates inferring the age of the Earth through radiometric dating of meteorites. Both estimates are over 4.5 billion years.

(no entry for this year)

1954

Elso Barghoorn and Stanley Tyler report the discovery of bacterial cells in Canadian rock formations that are nearly 2 billion years old.

Philip Abelson and his team detect amino acids in fish that are over 300 million years old.

image S. Benzer works out the fine structure of the rII region of phage T4 of E. coli, and coins the terms CISTRON,RECON, and MUTON.

1955

image S. Benzer works out the fine structure of the rII region of phage T4 of E. coli, and coins the terms CISTRON,RECON, and MUTON.

image Professional pipefitter and amateur paleontologist Francis Tully finds an enigmatic fossil near Morris, Illinois. Dating from about 300 million years ago, the fossil will be formally named Tullimonstrum gregarium and nicknamed the Tully monster. Although it will defy classification for decades, it will nevertheless be named the state fossil of Illinois.

F. Jacob and E. L. Wollman are able experimentally to interrupt the mating process in E. coli and show that a piece of DNA is inserted from the donor bacterium into the recipient.

1956

F. Jacob and E. L. Wollman are able experimentally to interrupt the mating process in E. coli and show that a piece of DNA is inserted from the donor bacterium into the recipient.

Fifteen-year-old English schoolgirl Tina Negus finds a specimen of the fossil species that will later be named Charnia masoni, from the geologic period that will later be named the Ediacaran. Unfortunately, Negus can't convince her geography teacher that the fossil she has found is Precambrian and gives up, leaving the fossil to be extracted by local schoolboy Roger Mason the next year.

Keith Runcorn publishes a paper describing polar wandering based on paleomagnetic studies of Europe and North America. He suggests continental drift, but his paper attracts little attention.

Paleontologist M. W. de Laubenfels publishes a paper suggesting that the dinosaurs were driven to extinction by a meteorite impact. His paper will not be taken seriously, but this hypothesis will be presented again in 1980 with more compelling evidence.

Brian Logan and fellow geologists find living stromatolites in Shark Bay, Australia. The find is somewhat surprising as stromatolites have no defenses against mouth-bearing organisms and have probably been relatively rare since the Cambrian Period.

Francis Crick proposes the "central dogma" of genetic information transfer: DNA specifies RNA and RNA specifies cell proteins.

V. M. Ingram reports that normal and sickle-cell hemoglobin differ by a single amino acid substitution.

1957

Francis Crick proposes the "central dogma" of genetic information transfer: DNA specifies RNA and RNA specifies cell proteins.

V. M. Ingram reports that normal and sickle-cell hemoglobin differ by a single amino acid substitution.

The Soviet Union launches Sputnik.

Frederick Sanger receives a Nobel Prize in Chemistry for his work on the structure of proteins, especially that of insulin.

George W. Beadle, Edward L. Tatum, and Joshua Lederberg share a Nobel Prize in Medicine for Beadle and Tatum's discovery that genes act by regulating definite chemical events, and for Lederberg's discoveries concerning genetic recombination and the organization of the genetic material of bacteria.

image F. H. C. Crick suggests that during protein formation the amino acid is carried to the template by an adaptor molecule containing nucleotides and that the adaptor is the part that actually fits on the RNA template. Crick thus predicts the discovery of transfer RNA.

F. Jacob and E. L. Wollman demonstrate that the single linkage group of E. coli is circular and suggest that the different linkage groups found in different Hfr strains result from the insertion at different points of a factor in the circular linkage group that determines the rupture of the circle.

M. Meselson and F. W. Stahl use the density gradient equilibrium centrifugation technique to demonstrate the semiconservative distribution of density label during DNA replication in E. coli.

1958

Frederick Sanger receives a Nobel Prize in Chemistry for his work on the structure of proteins, especially that of insulin.

George W. Beadle, Edward L. Tatum, and Joshua Lederberg share a Nobel Prize in Medicine for Beadle and Tatum's discovery that genes act by regulating definite chemical events, and for Lederberg's discoveries concerning genetic recombination and the organization of the genetic material of bacteria.

image F. H. C. Crick suggests that during protein formation the amino acid is carried to the template by an adaptor molecule containing nucleotides and that the adaptor is the part that actually fits on the RNA template. Crick thus predicts the discovery of transfer RNA.

F. Jacob and E. L. Wollman demonstrate that the single linkage group of E. coli is circular and suggest that the different linkage groups found in different Hfr strains result from the insertion at different points of a factor in the circular linkage group that determines the rupture of the circle.

M. Meselson and F. W. Stahl use the density gradient equilibrium centrifugation technique to demonstrate the semiconservative distribution of density label during DNA replication in E. coli.

Severo Ochoa and Arthur Kornberg share a Nobel Prize in Medicine for their discovery of the mechanisms in the biological synthesis of ribonucleic acid and deoxiribonucleic acid.

J. Lejeune, M. Gautier, and R. Turpin show that Down syndrome is a chromosomal aberration involving trisomy of a small telocentric chromosome.

R. L. Sinsheimer demonstrates that bacteriophage phiX174 of E. coli contains a single-stranded DNA molecule.

1959

Severo Ochoa and Arthur Kornberg share a Nobel Prize in Medicine for their discovery of the mechanisms in the biological synthesis of ribonucleic acid and deoxiribonucleic acid.

J. Lejeune, M. Gautier, and R. Turpin show that Down syndrome is a chromosomal aberration involving trisomy of a small telocentric chromosome.

R. L. Sinsheimer demonstrates that bacteriophage phiX174 of E. coli contains a single-stranded DNA molecule.

Mary Leakey finds hominid skull belonging to Paranthropus boisei.

Alister Hardy promotes his Homo aquaticus or "aquatic ape" hypothesis to the British Sub Aqua Club. He will follow up this announcement with several magazine articles.

1960

Alister Hardy promotes his Homo aquaticus or "aquatic ape" hypothesis to the British Sub Aqua Club. He will follow up this announcement with several magazine articles.

image image F. Jacob and J. Monod publish "Genetic regulatory mechanisms in the synthesis of proteins," a paper in which the theory of the OPERON is developed.

1961

Gene Shoemaker and E.C.T. Chao publish a paper characterizing the Ries Basin in Bavaria as the result of a meteorite impact. This will help pave the way for eventual acceptance of asteroid and comet impacts as potential causes of mass extinction.

image image F. Jacob and J. Monod publish "Genetic regulatory mechanisms in the synthesis of proteins," a paper in which the theory of the OPERON is developed.

Martin Glaessner determines fossils in the Ediacara Hills of South Australia (Ediacaran fauna) to be Precambrian in age (approximately 600 million years old), making them the oldest-known multicelled organisms.

Human geneticist James Neel develops the "thrifty genotype" hypothesis that human ancestors endured feast-famine cycles that made the human body very effective in storing fat for lean times.

image image image James Watson, Francis Crick, and Maurice Wilkins share a Nobel Prize in Medicine for their work in elucidating the structure of DNA.

1962

Human geneticist James Neel develops the "thrifty genotype" hypothesis that human ancestors endured feast-famine cycles that made the human body very effective in storing fat for lean times.

image image image James Watson, Francis Crick, and Maurice Wilkins share a Nobel Prize in Medicine for their work in elucidating the structure of DNA.

(no entry for this year)

1963

Lantian Man, a 500,000-year-old Homo erectus specimen, is found in Lantian County, China, just north of Xi'an.

Fred Vine and Drum Matthews publish a paper describing magnetic stripes formed at ocean ridges. Their findings will pave the way for the acceptance of continental drift over the next decade.

(no entry for this year)

1964

Louis Leakey describes Homo habilis, meaning "handy." The new species designation is not well received by the scientific community.

Two deciduous molars, roughly 44,000 years old, are collected at Grotta del Cavallo in southeastern Italy. After an initial classification as Neanderthal, they will be assigned to modern humans in a 2011 study.

Vincent Dethier publishes "Microscopic Brains," an article on insect behavior, in Science. He calls for a more empathetic approach to animal subjects, even tiny invertebrates.

W. Brian Harland and Martin J. S. Rudwick publish a theory that the Earth experienced a great ice age in the Neoproterozoic (late Precambrian). Rudwick suggests that the climate's return to moderate conditions paved the way for the evolution of multicelluar life.

1965

image image image François Jacob, André Lwoff, and Jacques Monod share a Nobel Prize in Medicine for their discoveries concerning genetic control of enzyme and virus synthesis.

N.H. Field publishes "Fossil sea-echinoids from a Romano-British site" describing the centuries-long occupation of a Romano-British settlement in Dorset. Newer buildings have been built upon older ones, with fossil urchins in each.

Willi Hennig works on a new approach to assessing evolutionary relationships, known as cladistics. Although it will be hotly debated, this technique will eventually become standard practice in paleontology, botany and zoology.

1966

Willi Hennig works on a new approach to assessing evolutionary relationships, known as cladistics. Although it will be hotly debated, this technique will eventually become standard practice in paleontology, botany and zoology.

Harry Whittington begins reexamining Burgess Shale fossils originally identified by Charles Walcott starting in 1909. Over the next two decades, Whittington (with the assistance of his graduate students Simon Conway Morris and Derek Briggs), will eventually overturn some of Walcott's theories and propose that most of the animals left no living relatives.

Lynn Sagan (later Lynn Margulis) hypothesizes that chloroplasts originated as cyanobacteria, and that mitochondria originated as bacteria. She suggests that both were engulfed by other cells and began functioning as symbionts.

1967

Lynn Sagan (later Lynn Margulis) hypothesizes that chloroplasts originated as cyanobacteria, and that mitochondria originated as bacteria. She suggests that both were engulfed by other cells and began functioning as symbionts.

Graduate student S.B. Misra discovers a well-preserved sea floor with numerous fossils dating from the late Precambrian (later to be dubbed the Ediacaran Period) at Mistaken Point, Newfoundland.

P. S. Martin suggests that fast-moving bands of human hunters caused the extinctions of Pleistocene big-game species.

Richard Leakey finds two fossil skulls, Omo I and Omo II, in Ethiopia. Though initially dated at 130,000 years, the fossils will later be dated (using argon decay) at 195,000 years, and designated as the oldest examples so far found of Homo sapiens.

Daniel Janzen argues that, because they live under "easy" conditions, tropical plants cannot likely survive a wide range of temperature, light, or hydrologic conditions.

A.G. Cairns-Smith publishes a paper suggesting that the first life on Earth might have been fine-grained clay crystals. He will publish on this topic several more times before his death, but the experimental evidence will remain scant, perhaps in part because sufficient technology doesn't yet exist to test the hypothesis.

Robert W. Holley, Har Gobind Khorana, and Marshall W. Nirenberg share a Nobel Prize in Medicine for their interpretation of the genetic code and its function in protein synthesis.

1968

A.G. Cairns-Smith publishes a paper suggesting that the first life on Earth might have been fine-grained clay crystals. He will publish on this topic several more times before his death, but the experimental evidence will remain scant, perhaps in part because sufficient technology doesn't yet exist to test the hypothesis.

Robert W. Holley, Har Gobind Khorana, and Marshall W. Nirenberg share a Nobel Prize in Medicine for their interpretation of the genetic code and its function in protein synthesis.

Richard Fox describes a Paleocene mammal, Prothryptacodon albertensis, retrieved from a well dug in Alberta, Canada. This find eerily resembles that of another Paleocene mammal recovered from a Louisiana oil well and described in 1932 by George Gaylord Simpson.

Teenaged fossil enthusiast Tadashi Suzuki finds a plesiosaur fossil in his hometown of Iwaki City, Japan. The fossil turns out to be a new species, but it won't be identified as such for nearly 40 years.

1969

R. H. Whittaker proposes to divide all living things into five kingdoms: Animalia, Plantae, Fungi, Protista and Monera.

Max Delbrück, Alfred D. Hershey, and Salvador E. Luria share a Nobel Prize in Medicine for their discoveries concerning the replication mechanism and the genetic structure of viruses.

Archaeologist Joachim Hahn pieces together the fragments of the lion- headed man found 30 years earlier the Hohlenstein-Stadel Cave in Germany.

image John Ostrom publishes Osteology of Deinonychus antirrhopus, an Unusual Theropod from the Lower Cretaceous of Montana — a description of Deinonychus with a frontispiece illustration by Bob Bakker, suggesting that the dinosaur is alert, agile and intelligent.

Americans land the first man on the moon.

(no entry for this year)

1970

(no entry for this year)

Five pairs of adult wall lizards are moved between two islands in Croatia. Over the next few decades, the lizards on the new island will evolve larger heads, stronger bites, and a greater tolerance for an herbivorous diet than the original lizard population.

1971

Five pairs of adult wall lizards are moved between two islands in Croatia. Over the next few decades, the lizards on the new island will evolve larger heads, stronger bites, and a greater tolerance for an herbivorous diet than the original lizard population.

A. G. Sharov describes a pterosaur with fossil "hair" impressions as Sordes pilosus (hairy devil).

Grad student Douglas Lawson discovers the humerus of a giant pterosaur in Texas. Over the next four years, he will continue collecting and finally publish a description of Quetzalcoatlus northropi, the largest flying animal ever found, with an estimated wingspan of 39 feet.

Polish and Mongolian paleontologists discover the entwined skeletons of a Protoceratops and a juvenile Velociraptor in the Gobi Desert, most likely locked in mortal combat.

1972

Stephen Jay Gould and Niles Eldredge publish their theory of punctuated equilibrium, stating that evolution often occurs in short bursts, followed by long periods of stability.

Christian B. Anfinsen, Stanford Moore, and William H. Stein share a Nobel Prize in Chemistry, with Anfinsen cited for his work on ribonuclease, especially concerning the connection between the amino acid sequence and the biologically active conformation, and Moore and Stein cited for their contribution to the understanding of the connection between chemical structure and catalytic activity of the active centre of the ribonuclease molecule.

Bob Bakker publishes "Anatomical and Ecological Evidence of Endothermy in Dinosaurs" in Nature, arguing that dinosaurs were warm-blooded animals.

Harry Whittington shows a preliminary reconstruction of the Burgess Shale species Opabinia at a Palaeontological Association meeting, and the crowd roars with laughter.

Half in jest, Francis Crick and Leslie Orgel suggest that ancient aliens may have seeded the early Earth with DNA, and all life on this planet arose from that.

Peter and Rosemary Grant begin a long-term study of finches on the Galápagos Islands. In succeeding years, as they watch finches adapt to alternating wet and dry conditions, the Grants will uncover evidence that evolution proceeds more rapidly than what Darwin estimated.

Taking a line from Through the Looking Glass, Leigh Van Valen establishes the "Red Queen" hypothesis of coevolution between predator and prey: "it takes all the running you can do, to keep in the same place. If you want to get somewhere else, you must run at least twice as fast as that!"

1973

Half in jest, Francis Crick and Leslie Orgel suggest that ancient aliens may have seeded the early Earth with DNA, and all life on this planet arose from that.

Peter and Rosemary Grant begin a long-term study of finches on the Galápagos Islands. In succeeding years, as they watch finches adapt to alternating wet and dry conditions, the Grants will uncover evidence that evolution proceeds more rapidly than what Darwin estimated.

Taking a line from Through the Looking Glass, Leigh Van Valen establishes the "Red Queen" hypothesis of coevolution between predator and prey: "it takes all the running you can do, to keep in the same place. If you want to get somewhere else, you must run at least twice as fast as that!"

Heinz Tobien collects a primate tooth fragment from limestone rocks in southern Germany. Studies published decades later, in 2001 and 2011, will suggest that the fossil is 17 million years old, and that a hominoid migration into Eurasia occurred 3 million years earlier than previously thought.

(no entry for this year)

1974

Donald Johanson and his team discover a female fossil hominid (to be later named Australopithecus afarensis) and call her Lucy. Lucy's discovery establishes that hominids walked upright before developing large brains, overturning some long-held beliefs about hominid evolution. Her status as a direct ancestor of modern humans, however, will remain controversial.

Heavy equipment operator Porky Hansen accidentally uncovers a mammoth tusk while leveling ground for a building. The site will reveal many more mammoths, becoming a tourist attraction for Hot Springs, South Dakota.

John Ostrom publishes a paper titled "Archaeopteryx and the Origin of Flight" reviving Thomas Henry Huxley's arguments from the 1860s.

Mary-Claire King and Allan Wilson publish their finding that human and chimpanzee DNA sequences differ by roughly 1 percent, meaning humans have more in common with chimps than chimps do with gorillas. King and Wilson suggest that humans and chimps differ largely in the DNA that switches on and off genes.

David Baltimore, Renato Dulbecco, and Howard Temin share Nobel Prize in Medicine for their discoveries concerning the interaction between tumour viruses and the genetic material of the cell.

1975

Mary-Claire King and Allan Wilson publish their finding that human and chimpanzee DNA sequences differ by roughly 1 percent, meaning humans have more in common with chimps than chimps do with gorillas. King and Wilson suggest that humans and chimps differ largely in the DNA that switches on and off genes.

David Baltimore, Renato Dulbecco, and Howard Temin share Nobel Prize in Medicine for their discoveries concerning the interaction between tumour viruses and the genetic material of the cell.

Armed with an old geological map, selt-taught fossil hunter Joan Wiffin finds New Zealand's first recognized dinosaur fossil, a theropod tail vertebra, in the Maungahouanga Valley.

Overturning the classifications introduced by R. H. Whittaker seven years earlier, Carl Woese proposes to divide all living things into three categories: Bacteria, Archaea and Eukarya.

1976

Overturning the classifications introduced by R. H. Whittaker seven years earlier, Carl Woese proposes to divide all living things into three categories: Bacteria, Archaea and Eukarya.

Paleontologists looking for cave bear remains explore Sima de los Huesos ("Pit of the Bones") at Atapuerca, Spain. For many years afterwards, it will remain the densest accumulation of fossil human bones ever discovered, including the remains of more than 30 Homo heidelbergensis individuals.

Submersible vehicle Alvin reveals deep sea vents on the ocean floor that give rise to an ecosystem owing nothing to photosynthesis. This finding prompts speculation that life on Earth first arose in deep-sea, not shallow-water, ecosystems.

Fred Sanger and collaborators publish the first complete DNA sequence of an organism, a bacteriophage, or virus infecting bacteria.

1977

Submersible vehicle Alvin reveals deep sea vents on the ocean floor that give rise to an ecosystem owing nothing to photosynthesis. This finding prompts speculation that life on Earth first arose in deep-sea, not shallow-water, ecosystems.

Fred Sanger and collaborators publish the first complete DNA sequence of an organism, a bacteriophage, or virus infecting bacteria.

1978

F. Metzger-Krahé describes a ninth-century Viking settlement in southern Jutland — perhaps the first city-like settlement in Northern Europe — holding 185 fossils, most of them sea urchins.

Werner Arber, Dan Nathans, and Hamilton Smith share a Nobel Prize in Medicine for the discovery of restriction enzymes and their application to problems of molecular genetics.

J. W. Kitching discovers a clutch of prosauropod eggs in South Africa, the oldest dinosaur embryos yet found. They will show that sauropods walked on all fours as small animals, but the significance of this find will be overlooked for nearly three decades.

Mary Leakey announces the discovery of fossil footprints at Laetoli demonstrating that hominids walked upright 3.6 million years ago.

image Fresh out of law school and short on cash, Robert Heggestad buys an antique cabinet on an installment plan from a Virginia antique shop. The cabinet turns out to contain some 1,700 plant and invertebrate specimens from the personal collection of Alfred Russel Wallace.

1979

image Fresh out of law school and short on cash, Robert Heggestad buys an antique cabinet on an installment plan from a Virginia antique shop. The cabinet turns out to contain some 1,700 plant and invertebrate specimens from the personal collection of Alfred Russel Wallace.

Crystal Bennett finds a human-altered sea urchin fossil in Islamic (Fatimid) deposits dating from the 10th to 12th centuries in the Amman Citadel.

The Geological Society of America awards 96-year-old Harlen Bretz the Penrose Medal for identifying the cause of the Channeled Scablands in the northwestern United States: a massive flood from Glacial Lake Missoula after it broke through its ice dam. The recognition is somewhat late as Bretz first hypothesized a megaflood in the 1920s.

Christiane Nüsslein-Volhard and Eric Wieschaus describe genetic mutations affecting the body plan of the fruit fly Drosophila, and identify genes controlling the basic body plans of all animals. These genes will eventually be known as Hox genes.

Paul Berg, Walter Gilbert, and Frederick Sanger share a Nobel Prize in Chemistry, with Berg cited for his fundamental studies of the biochemistry of nucleic acids, with particular regard to recombinant-DNA, and Gilbert and Sanger cited for their contributions concerning the determination of base sequences in nucleic acids. This is Sanger's second Nobel, the first having come in 1958 for his work on the structure of insulin.

1980

Christiane Nüsslein-Volhard and Eric Wieschaus describe genetic mutations affecting the body plan of the fruit fly Drosophila, and identify genes controlling the basic body plans of all animals. These genes will eventually be known as Hox genes.

Paul Berg, Walter Gilbert, and Frederick Sanger share a Nobel Prize in Chemistry, with Berg cited for his fundamental studies of the biochemistry of nucleic acids, with particular regard to recombinant-DNA, and Gilbert and Sanger cited for their contributions concerning the determination of base sequences in nucleic acids. This is Sanger's second Nobel, the first having come in 1958 for his work on the structure of insulin.

image Louis W. Alvarez, Walter Alvarez, Frank Asaro and Helen V. Michel publish their asteroid impact theory of dinosaur extinction. The theory will not gain widespread acceptance among scientists for several years.

(no entry for this year)

1981

(no entry for this year)

(no entry for this year)

1982

(no entry for this year)

1983

Barbara McClintock receives the Nobel Prize in Medicine for her discovery of mobile genetic elements.

German paleobiologist Adolf Seilacher suggests that most of the Ediacaran fossils discovered in the 1940s are not related to any modern forms. Calling them vendobionts, he argues that they went extinct after the emergence of large predators. Seilacher's interpretation, however, will remain in dispute.

David Raup and Jack Sepkoski publish the controversial claim that mass extinctions are regularly spaced at 26 million years.

1984

David Raup and Jack Sepkoski publish the controversial claim that mass extinctions are regularly spaced at 26 million years.

Richard Leakey and his team discover Turkana Boy, the most complete Homo erectus fossil yet discovered.

(no entry for this year)

1985

Kenneth Oakley publishes Decorative and Symbolic Uses of Fossils describing, among other things, a hand axe crafted by Homo heidelbergensis featuring a fossil sea urchin, and a fossil urchin set within a bronze locket from a Gallo-Roman temple.

Paleoanthropologists excavate an artifact-rich portion of Cueva de los Aviones in Iberia. Fifty-thousand-year-old perforated and pigment-stained shells from the cave will prompt researchers to argue, 25 years later, that Neanderthals wore both makeup and jewelry.

(no entry for this year)

1986

Norman H. Sleep submits a paper calculating the probability of life forms surviving an extraterrestrial impact in the Hadean Period (first 700 million years of Earth's existence). The paper is rejected on the grounds there would have been no life on Earth yet.

Allan Wilson and Rebecca Cann announce that all humans share a common ancestor who lived in Africa as recently as 150,000 years ago. Because the discovery is based on examination of mitochondrial DNA, the ancestral entity will be given the popular (and somewhat misleading) name of "Mitochondrial Eve." The controversial finding will be supported by another discovery in 2000.

1987

Allan Wilson and Rebecca Cann announce that all humans share a common ancestor who lived in Africa as recently as 150,000 years ago. Because the discovery is based on examination of mitochondrial DNA, the ancestral entity will be given the popular (and somewhat misleading) name of "Mitochondrial Eve." The controversial finding will be supported by another discovery in 2000.

Jenny Clack finds Acanthostega, the most complete Devonian tetrapod yet discovered. It has evidence for functional gills as well as legs, strongly suggesting that animals evolved legs while still living in the water.

Kansas rancher Charles Bonner collects a plesiosaur mother-and-fetus fossil. Nearly 25 years later, O'Keefe and Chiappe will describe this as evidence that that plesiosaurs gave live birth and might have been attentive mothers.

Dhananjay Mohabey discovers what looks like a simple clutch of dinosaur eggs in India. Twenty-three years later, he, Jeffrey Wilson and colleagues will report that the fossil find includes not just sauropod eggs, but a predatory Cretaceous snake that apparently snacked on hapless sauropod hatchlings.

Molecular biologist John Cairns describes experiments suggesting that bacteria facing environmental stress can "direct" their mutations to produce favorable adaptations. Directed mutation will remain a controversial idea, but the possibility that organisms mutate at a greater rate (hypermutation) under environmental stress will gain more acceptance.

1988

Molecular biologist John Cairns describes experiments suggesting that bacteria facing environmental stress can "direct" their mutations to produce favorable adaptations. Directed mutation will remain a controversial idea, but the possibility that organisms mutate at a greater rate (hypermutation) under environmental stress will gain more acceptance.

1989

Sidney Altman and Thomas R. Cech share a Nobel Prize in Chemistry for their discovery of catalytic properties of RNA.

Ned Colbert finally completes his definitive species description of the Coelophysis dinosaurs he found in 1947.

Philip Gingerich finds a fossil whale, Basilosaurus in Egypt. It has tiny legs, just inches long, retaining all five toes. Five years later, he will discover an even more primitive whale ancestor, Rodhocetus, with even bigger hind legs, in Pakistan. Eighteen years later, Hans Thewissen will announce the discovery of another missing link in cetacean evolution: fox- like Indohyus found in Kashmir.

The Human Genome Project is launched with the goal of sequencing all 3 billion base pairs of human DNA by 2005.

1990

The Human Genome Project is launched with the goal of sequencing all 3 billion base pairs of human DNA by 2005.

Mongolia invites the American Museum of Natural History to reinstate excavations in the Gobi desert.

Scott Wing of the Smithsonian Institution discovers the Big Cedar Ridge fossil plant site in Wyoming. The locality will become known as the Pompeii of Cretaceous plants.

Chicxulub crater is discovered in the Yucatán Peninsula, supporting the asteroid impact theory first suggested in 1980.

1991

Chicxulub crater is discovered in the Yucatán Peninsula, supporting the asteroid impact theory first suggested in 1980.

(no entry for this year)

1992

A team led by Tim White finds the first traces of a hominid fossil that will later be named Ardipithecus ramidus. Seventeen years later, the team will publish a detailed description of a 4.4-million-year-old, 120-centimeter-tall, nearly complete adult female, along with fossils from 35 other individuals. The team will argue that "Ardi" should supplant Lucy at the base of the hominid tree.

Ian Campbell and collaborators publish a paper pointing to the Siberian Traps, an area of massive volcanic activity, as the cause of the Permo- Triassic mass extinction 251 million years ago.

Paleontologists led by Jim Kirkland discover Utahraptor, a super-sized velociraptor that conveniently supports the super-sized velociraptors that will appear in the screen version of Jurassic Park a year later.

Suburban San Diego roadwork uncovers mastodon bones and broken rocks at what becomes known as the (Richard) Cerutti Mastodon site. Roadwork halts while paleontologist Tom Deméré examines the find. Twenty-five years later, Deméré, Cerutti and nine other researchers will contend that the site is evidence of human presence in North America 130,000 years ago.

Joe Kirschvink publishes "Late Proterozoic Low-latitude Glaciation: The Snowball Earth," a short book section in a specialized monograph. This snowball Earth hypothesis will attract little attention until expanded by Paul Hoffman and his collaborators several years later.

1993

Kary Mullis and Michael Smith share a Nobel Prize in Chemistry, with Mullis cited for his contributions to the developments of methods within DNA-based chemistry and Smith for his fundamental contributions to the establishment of oligonucleiotide-based, site-directed mutagenesis and its development for protein studies.

Richard J. Roberts, and Phillip A. Sharp share a Nobel Prize in Medicine for their discoveries of split genes.

A calcite-encrusted hominid skeleton is discovered in a karst cave near Altamura, Italy. About two decades later, researchers will date the rock layers and test a scapula fragment, eventually concluding that the skeleton is probably 128,000 to 187,000 years old, and ranks among so- called "early Neanderthals."

Geology student Iwan Stossel stumbles across a nearly 400-million-year-old tetrapod fossil trackway on the island of Valentia, County Kerry, Ireland.

J. William Schopf publishes a description of microfossils of the Apex Basalt in Australia. His claims that they are 3.5-billion-year-old microbes that could photosynthesize and produce oxygen will later be challenged. One of his challengers, Martin Brasier, will coauthor a 2011 study on microfossils from a nearby outcrop, claiming that the 3.4-billion- year-old microbes fed off sulfur.

On an expedition in the Gobi desert, paleontologists from the American Museum of Natural History discover the skeleton of an Oviraptor dinosaur crouching over a nest of eggs, apparently incubating them in the same fashion as modern birds.

Roland Anderson and Jennifer Mather publish "Personalities of Octopuses" in the Journal of Comparative Psychology.

(no entry for this year)

1994

Anthropologist Ron Clarke finds previously overlooked foot bones, showing both ape and human qualities, from Sterkfontein. Future finds will associate these bones with a skeleton nicknamed Little Foot.

image In what will later be named Chauvet Cave, French cavers discover 32,000-year-old paintings showing 400 animal images.

Using "molecular clock" estimates of mutation rates, Greg Wray and collaborators hypothesize that metazoan phyla diverged from each other 1 billion years ago, or even earlier. In other words, they argue that metazoans existed hundreds of millions of years before the earliest metazoan fossils (about 600 million years old) yet found.

1996

Using "molecular clock" estimates of mutation rates, Greg Wray and collaborators hypothesize that metazoan phyla diverged from each other 1 billion years ago, or even earlier. In other words, they argue that metazoans existed hundreds of millions of years before the earliest metazoan fossils (about 600 million years old) yet found.

Alan Walker and Pat Shipman publish a description of advanced Vitamin A poisoning in a 1.7-million-year-old Homo erectus skeleton. They assert that it is evidence of both meat eating, caused by consuming the liver of a large carnivore, and sufficient sociability in Homo erectus to care for an ill and incapacitated individual.

image Chen Pei Ji unveils Sinosauropteryx prima from Liaoning, China, the first feathered dinosaur discovered, at the Society of Vertebrate Paleontology's annual meeting. Fourteen years later, a team of Chinese and British paleontologists will argue that this animal had a striped tail, a reddish color alternating with white, based on pigment-rich microscopic spheres in the fossilized feathers.

The roughly 9,000-year-old Kennewick Man skeleton is found in the northwestern United States. Craniometric analysis initially suggests an affiliation to Ainu and Polynesian groups. Better DNA sampling methods will finally allow genetic analysis nearly 20 years later, and that will indicate a relationship closest to modern Native Americans.

Tim White's team discovers horse, antelope and other mammal bones with cut marks from stone tools — evidence of tool use 2.5 million years ago.

(no entry for this year)

1997

A team of archaeologists finds evidence of human occupation 14,000 years ago at Monte Verde, Chile, pushing back the arrival date of humans in the Americas.

Excavations near Koblenz in northern Germany turn up a Neanderthal skullcap, estimated at 170,000 years old, that was apparently used as a bowl.

Paleontologist Karen Chin receives a 17-inch coprolite excavated in Saskatchewan. Estimated at 65 million years old and full of crunched bone, it is likely the calling card of a T. rex.

Paleontologist Paul Sereno discovers the delicate Darth Vader-like skull of a dinosaur he will later name Nigersaurus taqueti and nickname the "Mesozoic Cow."

Two 5-foot-long Humboldt squid in the Sea of Cortez "mug" a diver working on a PBS documentary, making off with the gold chain hanging around the diver's neck, and demonstrating that Humboldt squid have bad manners but good taste.

(no entry for this year)

1998

Andrew Parker publishes a paper suggesting that some Cambrian animals (Wiwaxia, Canadia and Marella) developed flickering displays of iridescent color at about the same time that eyes evolved.

Aterian artifacts (named for stone tools discovered in Algeria in 1917) are estimated at 70,000 years old at sites in Libya. Over the next dozen years, the age of artifacts found at various sites in northern Africa will be pushed back to at least 110,000 years old.

Xiao, Zhang and Knoll describe fossilized animal embryos in Nature. Li, Chen and Hua simultaneously describe embryos in Science. The fossils all come from the Doushantuo phosphorites in southern China, and all are estimated to be about 570 million years old, making them the oldest fossil embryos so far discovered. Nine years later, however, Bailey and collaborators will challenge this interpretation, arguing the "fossil embryos" could just as easily be large bacteria. That challenge will be answered by the announcement of fossil embryos inside egg cysts.

Paul Hoffman, Alan Kaufman, Galen Halverson and Daniel Schrag publish a Neoproterozoic snowball Earth theory arguing that in the late Precambrian, the Earth underwent global glaciations followed by extreme greenhouse conditions, spurring the evolution of multicellular life forms.

(no entry for this year)

1999

Pierre-Jean Texier and colleagues begin studying etched ostrich shells from Diepkloof Rock Shelter in Western Cape, South Africa. Eleven years later, they will argue that the artifacts, numbering roughly 280, show evidence of graphic communication dating back 60,000 years.

Chinese paleontologists discover an exceptionally well-preserved feathered dinosaur, probably a juvenile dromaeosaur. Citing the confusion caused by language barriers and jet lag, the paleontologists' American collaborators nickname the fossil "Dave the fuzzy raptor," after a character alluded to in a Cheech and Chong routine. This fossil will be assigned to the genus Sinornithosaurus. (The next fuzzy discovery will be nicknamed "Chong.")

Based on studies of Y chromosomes, Peter Underhill publishes his finding that all modern humans share a common ancestor, bolstering the 1987 announcement from Cann and Wilson. This suggests a "bottleneck" event (population crash) among human ancestors living in Africa roughly 150,000 years ago.

Sally McBearty and Alison Brooks publish "The Revolution that Wasn't" challenging the long-held notion of a "big bang" in human intellectual evolution approximately 40,000 years ago. Instead, they cite evidence for earlier appearances of modern behavior.

2000

Based on studies of Y chromosomes, Peter Underhill publishes his finding that all modern humans share a common ancestor, bolstering the 1987 announcement from Cann and Wilson. This suggests a "bottleneck" event (population crash) among human ancestors living in Africa roughly 150,000 years ago.

Sally McBearty and Alison Brooks publish "The Revolution that Wasn't" challenging the long-held notion of a "big bang" in human intellectual evolution approximately 40,000 years ago. Instead, they cite evidence for earlier appearances of modern behavior.

A research team led by Paul Sereno discovers Rugops primus ("first wrinkle face") in the Sahara. This dinosaur's resemblance to South American fossils suggests that Africa separated from the ancient landmass of Gondwana more recently than previously thought.

Phil Currie publishes a paper suggesting that T. rex was a social animal that hunted in packs.

image Alfred Sturtevant's A History of Genetics is republished jointly by the Electronic Scholarly Publishing Project and the Cold Spring Harbor Laboratory Press. Sturtevant provides an insider's perspective (he created the FIRST GENETIC MAP ) to this first-rate summary of the foundations of classical genetics.

CLICK HERE TO BUY THIS BOOK

The International Human Genome Sequencing Consortium (Human Genome Project) publishes the initial sequence and analysis of the human genome in Nature Magazine. Celera Genomics simultaneously publishes a draft human genome sequence in Science Magazine.

Leland H. Hartwell, R. Timothy Hunt, and Sir Paul M. Nurse share a Nobel Prize in Medicine for their discoveries of key regulators of the cell cycle.

2001

image Alfred Sturtevant's A History of Genetics is republished jointly by the Electronic Scholarly Publishing Project and the Cold Spring Harbor Laboratory Press. Sturtevant provides an insider's perspective (he created the FIRST GENETIC MAP ) to this first-rate summary of the foundations of classical genetics.

CLICK HERE TO BUY THIS BOOK

The International Human Genome Sequencing Consortium (Human Genome Project) publishes the initial sequence and analysis of the human genome in Nature Magazine. Celera Genomics simultaneously publishes a draft human genome sequence in Science Magazine.

Leland H. Hartwell, R. Timothy Hunt, and Sir Paul M. Nurse share a Nobel Prize in Medicine for their discoveries of key regulators of the cell cycle.

image Chris Henshilwood and collaborators discover and describe 77,000-year-old artwork: stones carved with lines and triangles, from Blombos Cave on the Southern Cape coast of Africa. Three years later, Henshilwood and collaborators will describe more Blombos artifacts: tiny snail shells that were apparently pierced and worn as jewelry about 76,000 years ago. A few years after that, another research team will describe similar shell beads, at least 100,000 years old, in Israel and Algeria.

Joshua Smith and collaborators publish a description of a giant sauropod from Egypt, possibly the largest Cretaceous sauropod yet discovered. It is considered a possible food source for three large carnivorous dinosaur species discovered decades earlier by Ernst Stromer.

Luann Becker and collaborators publish a paper describing carbon fullerenes (buckyballs) at the Permo-Triassic boundary in China, Japan and Hungary. Because they can occur in meteorites, the fullerenes are cited as evidence of a meteorite impact at the end of the Permian. Other scientists will have difficulty reproducing their results, however, and the researchers' claim will remain controversial.

Odin and Néraudeau publish a description of a Neanderthal flint tool found in southwestern France with a fossil sea urchin on one side.

2002

Sydney Brenner, H. Robert Horvitz, and John E. Sulston share a Nobel Prize in Medicine for their discoveries concerning genetic regulation of organ development and programmed cell death.

David Lordkipanidze and collaborators excavate a 1.77-million-year-old Homo erectus skull of a "toothless old man" in Dmanisi. New bone growth after the loss of his teeth suggests that he was cared for by others, the oldest evidence yet found of care for the sick in fossil hominids.

Michel Brunet and collaborators publish a description of Sahelanthropus tchadensis, a hominid fossil from western central Africa. Suspected to be 6 to 7 million years old, it is possibly the oldest hominid fossil yet found. Its location, in Chad, is expected to spur hominid fossil hunting west of Africa's Rift Valley.

(no entry for this year)

2003

M.R. Sánchez-Villagra, O. Aguilera and I. Horovitz publish a description of Phoberomys, a fossil rodent from Venezuela the size of a buffalo.

Paleontologists in Germany identify the world's oldest pantry: an underground burrow system probably dug by an extinct species of ground squirrel or hamster. Estimated at 17 million years old, the food stash is stuffed with more than 1,800 fossilized nuts.

Paleontologists led by John Horner find a T. rex fossil that will later yield evidence of blood vessels and blood cells. The fossil will also prove to be an egg-laying female.

Two separate teams, digging 2,000 miles apart, find two new Antarctic dinosaurs in the same week. One appears to be a Jurassic sauropod, the other a Cretaceous theropod.

Peter Brown, Mike Morwood and collaborators announce the find of a 1-meter- tall hominid skeleton on the Indonesian island of Flores. Found near the remains of giant lizards and pygmy elephants, the new species is formally named Homo floresiensis and nicknamed the "hobbit." Though some suspect it's a kind of malformed, small-brained midget, this interpretation will be answered by braincase scans, wrist bones too primitive to be Homo sapiens, and the announcement of several more individuals of the same species. Later studies will suggest direct ancestry from Homo erectus, although another study will argue the remains really indicate Down syndrome. The species is initially given an estimated age as young as 11,000 years, but later research will indicate an age of at least 50,000 years.

2004

Peter Brown, Mike Morwood and collaborators announce the find of a 1-meter- tall hominid skeleton on the Indonesian island of Flores. Found near the remains of giant lizards and pygmy elephants, the new species is formally named Homo floresiensis and nicknamed the "hobbit." Though some suspect it's a kind of malformed, small-brained midget, this interpretation will be answered by braincase scans, wrist bones too primitive to be Homo sapiens, and the announcement of several more individuals of the same species. Later studies will suggest direct ancestry from Homo erectus, although another study will argue the remains really indicate Down syndrome. The species is initially given an estimated age as young as 11,000 years, but later research will indicate an age of at least 50,000 years.

A 70-million-year-old mammal jaw is found in Pui, Romania, some 100 miles from Vlad Dracula's castle. Eleven years later, the animal will be formally named Barbatodon transylvanicus by scientists who note that strengthening iron, not blood drinking, gives the teeth their bright red color.

D. Néraudeau describes deposits in western France revealing hundreds of Acheulian and Mousterian tools, 12 of them bearing fossils.

Heather Wilson and Lyall Anderson publish a paper describing the oldest land animal fossil yet discovered: Pneumodesmus newmani, a 428-million- year-old, centimeter-long millipede found by amateur fossil hunter Mike Newman.

M.-Y. Zhu and collaborators publish a description of munched trilobite parts inside another arthropod, confirming earlier suspicions that other animals snacked on the little water bugs.

Naama Goren-Inbar and her team announce the discovery of controlled fire use by hominids at a 790,000-year-old site in Israel, pushing the earliest known use of fire back 300,000 years from previous estimates.

Qingjin Meng and collaborators publish a description of an adult Psittacosaurus dinosaur associated with 34 juveniles, apparent evidence of parental care.

The British Museum begins an excavation project at Happisburgh in Norfolk. Over the next six years, researchers will uncover artifacts pushing back the earliest evidence of human activity at such a high latitude — 45 degrees — to perhaps as much as 950,000 years ago.

Using CT scans on femurs of the early hominid Orrorin tugenensis discovered in Kenya, Galik and collaborators push back the development of bipedalism in hominids to 6 million years ago (2 million years earlier than in Australopithecus anamensis).

X. Wang and Z. Zhou publish a description of the first known pterosaur egg containing an exquisitely preserved embryo. Though the egg is slightly smaller than the average chicken egg, the embryo sports a 27-centimeter wingspan. Several months later, Z. Zhou and F. Zhang publish a description of a Cretaceous bird embryo, the first found with feathers.

image A team of Japanese researchers take the first photograph ever of a giant squid in the wild. Unfortunately, they rip off one of the poor creature's tentacles in the process.

The International Union of Geological Sciences adds a new period to the Earth's geologic timescale: the Ediacaran. Ranging from approximately 600 million years ago to 542 million years ago, it begins after the last Snowball Earth ice age and precedes the Cambrian. It's the first new geologic period designated in 120 years.

(no entry for this year)

2005

M.A. Whyte announces the discovery of a 330-million-year-old trackway of a 5-foot-long, six-legged water scorpion (eurypterid) that could walk on land while the first tetrapods tried to do the same thing. Two years later, Simon Braddy, Markus Poschmann and collaborators will announce the find of fossil claw from an 8-foot eurypterid.

Yaoming Hu, Jin Meng, Yuanqing Wang and Chuankui Li publish a description of two large carnivorous mammals from the Cretaceous, one of which appears to have the remains of a diminutive dinosaur in its stomach. These fossils overturn long-held notions that Mesozoic mammals were all rat-sized plebeians scurrying around dinosaur feet.

Yohannes Haile-Selassie and colleagues announce the find of a nearly 4- million-year-old hominid from Ethiopia, possibly the remains of Australopithecus anamensis.

image Adrian Glover and Thomas Dahlgren announce the discovery of a new species of marine worm, discovered off the Swedish coast, that lives on whale bones on the sea floor. They name the species Osedax mucofloris.

Jean Moliner, Gerhard Ries, Cyril Zipfel and Barbara Hohn publish their findings on stressed plants that not only mutate at a greater rate, but also pass an increased mutation tendency to their offspring.

Andrew Z. Fine and Craig C. Mello share a Nobel Prize in Medicine for their discovery of RNA interference — gene silencing by double-stranded RNA.

Roger D. Kornberg was awarded a Nobel Prize in Chemistry for his studies of the molecular basis of eukaryotic transcription.

2006

Jean Moliner, Gerhard Ries, Cyril Zipfel and Barbara Hohn publish their findings on stressed plants that not only mutate at a greater rate, but also pass an increased mutation tendency to their offspring.

Andrew Z. Fine and Craig C. Mello share a Nobel Prize in Medicine for their discovery of RNA interference — gene silencing by double-stranded RNA.

Roger D. Kornberg was awarded a Nobel Prize in Chemistry for his studies of the molecular basis of eukaryotic transcription.

Jin Meng and collaborators describe a Mesozoic gliding mammal that pushes back the origin of mammalian flight by 70 million years, and suggests mammals maybe dabbled in flight earlier than birds.

Qiang Li and colleagues describe Castorocauda lutrasimilis, a Jurassic mammal that looked something like a mix between a beaver, otter, and platypus. Their discovery pushes back mammalian adaptation to an aquatic lifestyle by more than 100 million years.

The Research Council of Norway announces that oil drillers have struck a piece of dinosaur bone off the country's coast. At 1.4 miles below the North Sea, the bone fragment obtains the status of the world's deepest dinosaur.

Zeresenay Alemseged and collaborators publish a description of a 3.3- million-year-old partial skeleton from a juvenile Australopithecus afarensis from Ethiopia. The remains indicate that the australopithecene toddler walked upright and climbed trees.

Paleontologist Neil Clark suggests that some Loch Ness "sightings" may have been inspired by partial glimpses of traveling circus elephants taking dips in the lake.

2007

Divers find a submerged cavern in the Yucatán and name it Hoyo Negro. The cavern contains the remains of a teenage female who likely died between 12,000 and 13,000 years ago.

Mario R. Capecchi, Sir Martin J. Evans, and Oliver Smithies share a Nobel Prize in Medicine for their discoveries of principles for introducing specific gene modifications in mice by the use of embryonic stem cells.

Fred Spoor, Meave Leakey and collaborators describe remains of Homo habilis and Homo erectus from the same rock layer a short distance apart. The finds suggest that the two species coexisted in the same area for up to 500,000 years, and that H. erectus probably did not descend from H. habilis as previously thought.

John Kappelman and collaborators announce the find of a 500,000-year-old hominid skull from Turkey showing signs of tuberculosis. The researchers argue that condition could be induced by a Vitamin D deficiency resulting from a dark-skinned individual migrating to an area with less sunlight.

Kate Trinajstic and collaborators announce the discovery of 380-million- year-old Australian fossil fish sporting fossilized muscle.

Xing Xu and collaborators describe Gigantoraptor erlianensis, a 25- foot-long, 3,000-pound, bird-like dinosaur from Inner Mongolia. The find runs counter to earlier assumptions that dinosaurs necessarily got smaller as they acquired more features resembling those of birds.

After studying grunting fish, Andrew Bass and colleagues report that the part of the brain controlling volcalization is extremely primitive, and propose that vertebrates evolved the ability to communicate through sound some 400 million years ago.

2008

After studying grunting fish, Andrew Bass and colleagues report that the part of the brain controlling volcalization is extremely primitive, and propose that vertebrates evolved the ability to communicate through sound some 400 million years ago.

Based on studies of fossils and extant carnivores, Chris Carbone and collaborators suggest that sabertooth cats were sociable animals that hunted in packs.

Chinese and Brazilian researchers describe a sparrow-sized pterosaur from northeastern China. Although a juvenile, the pterosaur is no hatchling, and it's more mature than any of the smaller pterosaurs so far found. The researchers name the species Nemicolopterus crypticus meaning "hidden flying forest dweller."

Susan Evans, Marc Jones and David Krause describe a bowling-ball-sized fossil frog from Madagascar. Because the Cretaceous creature's closest living relative is in South America, the scientists posit a land link connecting South America, Antarctica and Madagascar. The frog is named Beelzebufo ampinga, translated loosely as "armored devil toad" or more loosely as "fossil frog from hell."

Gabriele Gentile and colleagues describe a previously overlooked pink iguana, referred to as "rosada," on the Galápagos Islands. The pink lizard species may represent the earliest divergence of land animals on the island chain that Charles Darwin made famous.

Elizabeth H. Blackburn, Carol W. Greider, and Jack W. Szostak share a Nobel Prize in Medicine for their discovery of how chromosomes are protected by telomeres and the enzyme telomerase.

Venkatraman Ramakrishnan, Thomas A. Steitz, and Ada E. Yonath share a Nobel Prize in Chemistry for their studies of the structure and function of the ribosome.

2009

Gabriele Gentile and colleagues describe a previously overlooked pink iguana, referred to as "rosada," on the Galápagos Islands. The pink lizard species may represent the earliest divergence of land animals on the island chain that Charles Darwin made famous.

Elizabeth H. Blackburn, Carol W. Greider, and Jack W. Szostak share a Nobel Prize in Medicine for their discovery of how chromosomes are protected by telomeres and the enzyme telomerase.

Venkatraman Ramakrishnan, Thomas A. Steitz, and Ada E. Yonath share a Nobel Prize in Chemistry for their studies of the structure and function of the ribosome.

Anthony Martin and colleagues announce the discovery of three 106-million- year-old burrows in Australia that they identify as dinosaur burrows, perhaps used by the ancient reptiles to keep warm during the winter when Australia was closer to the South Pole.

Australian paleontologists announce the find of Zac, a plant-munching sauropod, on a sheep farm — the same sheep farm where paleontologists discovered Cooper, an armor-plated titanosaur, in 2004.

Chris Henshilwood and collaborators describe 13 engraved ochre artifacts from South Africa's Blombos Cave, some dating back 100,000 years. This discovery supplements earlier finds pushing back the advent of human artwork.

Erik Seiffert and coauthors argue that "missing link" Darwinius masillae described earlier in the year is not an ancestor of modern apes and monkeys but instead of modern lemurs and lorises.

image Nicholas Conard and collaborators describe 35,000-year-old flutes, one nearly complete flute carved from bird bone, and flute fragments carved from ivory, discovered in Hohle Fels Cave in Ulm, Germany.

Ryan Kerney announces the discovery of algae (Oophila amblystomatis) living inside spotted salamander (Ambystoma maculatum) embryo cells — the first discovery of a photosynthetic symbiont living inside vertebrate cells.

Candy makers Hershey and Mars finance competing genomic sequences for cacao (the primary ingredient of chocolate).

Robert G. Edwards receives the Nobel prize in Medicine "for the development of in vitro fertilization"

2010

Ryan Kerney announces the discovery of algae (Oophila amblystomatis) living inside spotted salamander (Ambystoma maculatum) embryo cells — the first discovery of a photosynthetic symbiont living inside vertebrate cells.

Candy makers Hershey and Mars finance competing genomic sequences for cacao (the primary ingredient of chocolate).

Robert G. Edwards receives the Nobel prize in Medicine "for the development of in vitro fertilization"

Abderrazak El Albani and colleagues describe 2.1-billion-year-old macroscopic fossils from Gabon. The authors argue that the fossils are multicellular, pushing back the record of macroscopic life by more than 200 million years. The team also contends that the complex shapes of the fossils suggest cell signaling and coordinated growth.

Adam Brumm, Mike Morwood and colleagues publish a paper arguing that more than 40 stone artifacts found in situ and dated to approximately 1 million years ago indicate that the ancestors of Homo floresiensis (the "hobbits") arrived on Flores some 120,000 years earlier than previously thought.

Bulldozer operator Jesse Steele uncovers bones while digging a reservoir in Snowmass, Colorado. Excavations at the site will turn up more than 40 kinds of Ice Age animals.

Grzegorz Niedzwiedzki and colleagues publish a description of 395-million- year-old tetrapod tracks from Poland — 18 million years before tetrapods were thought to exist. The tracks' early date, large size and marine environment cause some skepticism about the find.

In the same week, separate research teams announce the finds of a 100- million-year-old mammal hair preserved in amber, and a 30-million-year- old pelican fossil with a 30-centimeter-long beak.

Meijer and Due announce the discovery of a 1.8-meter-tall, 16-kilogram, likely landlubbing, carnivorous stork (Leptoptilos robustus) on the island of Flores. Whether the storks ate Homo floresiensis juveniles, the hobbits hunted the storks, or everybody left each other alone is unresolved.

Nicholas Longrich describes a new dinosaur species from previously misidentified fossils at the American Museum of Natural History. Perhaps nudged by drinking buddies, he names the ceratopsian — with pretty heart shapes in its crest — Mojoceratops.

Scott Sampson and colleagues describe two species of exuberantly horned ceratopsian dinosaurs from late Cretaceous sediments in Utah: Utahceratops gettyi and Kosmoceratops richardsoni.

The Smithsonian opens its new human origins hall. A week later, Johannes Krause and colleagues announce the find of a fossil finger fragment from an unknown hominid from Siberia coincident with Neanderthals and modern humans (later dubbed Denisovans, and found distantly related to modern New Guineans). A few weeks after that, Lee Berger and colleagues announce the find of a new hominid from South Africa, Australopithecus sediba. Several weeks later, an international team announces a small DNA overlap between modern humans and Neanderthals that suggests interbreeding.

Two studies released in the same week indicate that modern Melanesians and Aboriginal Australians descended from an earlier migration out of Africa than did other populations. Further, the studies suggest that participants in the earlier migration interbred with Denisovans.

Bruce A. Beutler and Jules A. Hoffmann share the Nobel Prize in Medicine "for their discoveries concerning the activation of innate immunity"

2011

Two studies released in the same week indicate that modern Melanesians and Aboriginal Australians descended from an earlier migration out of Africa than did other populations. Further, the studies suggest that participants in the earlier migration interbred with Denisovans.

Bruce A. Beutler and Jules A. Hoffmann share the Nobel Prize in Medicine "for their discoveries concerning the activation of innate immunity"

Bruce Archibald and coauthors describe a hummingbird-sized flying ant species that hopped continents during the early Eocene.

Darren Naish and coauthors describe a 27.5-centimeter bird jaw from the Late Cretaceous found in Kazakhstan. With only the jaw, the paleontologists can't be sure whether it loped like an ostrich, or pelted unfortunate land lubbers with effluvia missiles from above.

Jianni Liu and colleagues describe Diania cactiformis, or "walking cactus." It's a kind of leggy worm known as a lobopodian that lived in the Cambrian Period some 520 million years ago. The authors indicate that it might be close to the ancestral line for arthropods — jointed animals ranging from lobsters to ladybugs.

John Paterson and coauthors report their findings on Anomalocaris, a meter- long Cambrian predator so weird its remains were once mistaken for a shrimp and a jellyfish. They find that its eyes, mounted on the ends of stalks, were compound eyes, each with 16,000 separate lenses. Like dragonfly eyes but supersized.

Junchang Lü and colleagues announce the find of a Jurassic fossil from China, a probable female pterosaur who died while laying an egg. The egg is tiny compared to the mother, and has a parchment-like eggshell. The find suggests that pterosaurs buried their eggs, and that females lacked head crests.

Lee Berger and coauthors publish several papers on Australopithecus sediba arguing that the species is a direct ancestor of modern humans and the family tree will need to be redrawn. Other paleoanthropologists aren't so sure. They do agree that the Sediba's weird mix of primitive and advanced features demonstrates remarkable hominid diversity.

Longrich and Olson describe a newly discovered wing feature on an extinct, flightless Jamaican bird named Xenicibis: built-in nunchucks.

Michael Waters and coauthors describe a stone tool assemblage at the Buttermilk Creek Complex in Texas documenting the presence of humans in the New World about 15,500 years ago — more than 2,000 years before the earliest Clovis sites.

On the sesquicentennial of its discovery, a new study challenges the status of Archaeopteryx as the earliest known bird. Xing Xu and coauthors argue that Archaeopteryx and newly discovered Xiaotingia are closer to nonavian dinosaurs. Reactions to the paper are mixed.

Relying on molecular dating and some (literally) lousy fossils, Vincent Smith and colleagues assert that lice have been rapidly evolving since well before the end of the Cretaceous, and may have hung out on feathered dinosaurs before annoying other species.

Esther Ullrich-Lüter and colleagues describe photoreceptors in sea urchin tube feet, meaning the animals may have functioned as big, compound eyes.

2012

Sir John B. Gurdon and Shinya Yamanaka share the Novbel Prize in Medicine "for the discovery that mature cells can be reprogrammed to become pluripotent"

A boy named Evgeniy Solinder discovers a well-preserved mammoth in the Siberian Arctic. Later examination will show evidence that the mammoth was killed by spear-wielding humans, and radiocarbon dating will indicate that the animal is 45,000 years old, pushing back the earliest known human occupation of the region by 10,000 years.

After examining fossil feathers with an electron microscope and comparing them to modern feathers, a team of American and Chinese scientists announces that Microraptor, a four-winged dinosaur from China probably had an iridescent sheen to its feathers.

Chinese and Canadian researchers announce the discovery of Yutyrannus huali, a distant T. rex relative in which the 1.5-ton adult still sported long filamentous feathers.

Clive Finlayson and coauthors argue that Neanderthals collected bird feathers for use in personal adornment.

Extrapolating from contemporary cows, a team of British scientists contends that sauropod flatulence, releasing the potent greenhouse gas methane, played a significant role in the Mesozoic's warm, moist climate.

Gregory Retallack publishes a paper arguing that Ediacaran fossils long thought to be marine animals were actually land-based lichens. His argument pushes back the beginning of land-based life by 65 million years. Anticipating "sharp intakes of breath in the paleontological community," Nature sets up a comment forum at the same time it publishes Retallack's paper.

Two studies, released the same week in Science and Nature and done partly by the same researchers, describe two groups of ancient tools from South Africa. The studies say that one group, estimated to be about 71,000 years old, has small bladelets likely made from heat-treated stone, and the other group, estimated to be about 500,000 years old, has spear tips.

Walter Joyce and coauthors announce a new discovery in Germany's Messel Pit, a famous Eocene fossil site. The discovery includes multiple pairs of fossil turtles petrified in a state of indelicacy.

A team of British and U.S. scientists describe the color mechanism of a brilliant iridescent blue African fruit, Pollia condensata. Like some beetle shells, butterfly wings, and bird feathers, the fruit gets its color from microscopic structures rather than pigments, but the fruit's coiled strands of cellulose are like nothing before discovered in nature.

An international team of researchers publishes a study indicating that aphids might be able to engage in a photosynthesis-like process, using carotenoids for the "capture of light energy."

Eric Rittmeyer and coauthors describe Paedophryne amauensis, a 7.7- millimeter-long frog from New Guinea, "the smallest known vertebrate species."

Frank Glaw and coauthors describe several new species of miniature chameleons from Madagascar. Among the tiniest is Brookensia micra, with juveniles little enough to stand on the head of a match.

While sorting and relocating the Cambridge Herbarium, a university librarian finds fungi and seaweed collected by Charles Darwin on his Beagle voyage, still wrapped in newspaper from 1828.

Based on new genetic research, David Reich, Svante Pääbo and collaborators announce at a Royal Society of London meeting that Denisovans bred with Neanderthals, ancestors of people now living in East Asia and Oceania, and another group of extinct archaic humans who were genetically dissimilar to both Neanderthals and modern humans. A few weeks later, Matthias Meyer, Svante Pääbo and coauthors describe the oldest hominin DNA sequence to date, from a 400,000-year-old femur from Spain's Sima de los Huesos. The mitochondrial DNA indicate an unexpected link to Denisovans.

Using genetic material from more than 300 individuals, including aboriginal Australians from the Northern Territory, a team of geneticists argues that Australians — long believed isolated from other populations for some 45,000 years — received substantial gene flow from India about 4,230 years ago.

James E. Rothman, Randy W. Schekman and Thomas C. Südhof share the Nobel Prize in Medicine "for their discoveries of machinery regulating vesicle traffic, a major transport system in our cells"

2013

Based on new genetic research, David Reich, Svante Pääbo and collaborators announce at a Royal Society of London meeting that Denisovans bred with Neanderthals, ancestors of people now living in East Asia and Oceania, and another group of extinct archaic humans who were genetically dissimilar to both Neanderthals and modern humans. A few weeks later, Matthias Meyer, Svante Pääbo and coauthors describe the oldest hominin DNA sequence to date, from a 400,000-year-old femur from Spain's Sima de los Huesos. The mitochondrial DNA indicate an unexpected link to Denisovans.

Using genetic material from more than 300 individuals, including aboriginal Australians from the Northern Territory, a team of geneticists argues that Australians — long believed isolated from other populations for some 45,000 years — received substantial gene flow from India about 4,230 years ago.

James E. Rothman, Randy W. Schekman and Thomas C. Südhof share the Nobel Prize in Medicine "for their discoveries of machinery regulating vesicle traffic, a major transport system in our cells"

Dale Greenwalt and coauthors describe a 46-million-year-old fossil female mosquito from Montana with traces of her last bloody meal (iron and porphyrin) in her bloated abdomen — strong evidence that these bugs have been irritating nicer animals for tens of millions of years.

David Legg describes a Cambrian arthropod with scissor-like front appendages. He names the species Kootenichela deppi after Johnny Depp.

David Lordkipanidze and coauthors publish a new paper on the hominid fossils from Dmanisi, Georgia. They argue that all the fossils from the site are Homo erectus, and make the controversial claim that hominid species found worldwide from that period — Homo erectus, Homo habilis, and Homo rudolfensis — might all belong to one species with a lot of variability.

Marie Soressi and coauthors contend that Neanderthals made leather-working tools similar to modern-day lissoirs used on pricey handbags.

Reporting on some 12 years of research at La Chapelle-aux-Saints, William Rendu and coauthors support the original interpretation of intentional Neanderthal burials. They conclude that the burial pits are not explained by natural processes and, unlike the site's scavenged animal bones, the relatively undamaged human remains at the site must have been buried quickly.

Robert DePalma and coauthors describe a likely T. rex tooth lodged between hadrosaur vertebrae. The authors also describe regenerated bone that "massively overgrew" after the hadrosaur was bitten. They cite the find as evidence that T. rex hunted, at least some of the time, and that this lucky hadrosaur lived to munch leaves another day.

Robert Reisz and collaborators announce the "discovery of an embryonic dinosaur bone bed from the Lower Jurassic of China, the oldest such occurrence in the fossil record." The find includes the remains of many individual dinosaurs at different stages of development.

2014

John O’Keefe, May-Britt Moser and Edvard I. Moser share the Nobel Prize in Medicine "for their discoveries of cells that constitute a positioning system in the brain"

image After reexamining mussel shells collected by Eugène Dubois in Indonesia in the 1890s, a team of researchers announces that one of the shells bears the oldest-yet-known geometric engraving. They date the shell at around 500,000 years and attribute the handiwork to Homo erectus.

Ainara Sistiaga and colleagues describe what they contend is the oldest human coprolite yet positively identified: a roughly 50,000-year-old Neanderthal calling card from El Salt, Spain. Their analysis indicates that Neanderthals balanced their meaty diets with nuts, berries and vegetables. Other researchers find the study intriguing but hope for confirmation that the fossil turd is from a human and not, say, a bear.

An international research team announces the age of Indonesian cave art, originally discovered in the 1950s. The authors state that radiometric dating indicates the artwork is about 40,000 years old, making it comparable in age to the oldest reliably dated art found in Europe. The authors describe one hand stencil from Sulawesi's Maros karsts as "the oldest known hand stencil in the world."

Matt Lamanna and coauthors describe Anzu wyliei, an bipedal, bird- like feathered dinosaur found in North and South Dakota. Measuring 11 feet and 500 pounds, the oviraptorosaur is nicknamed the "chicken from hell."

Nick Ashton and coauthors describe human footprints discovered along England's east coast in May 2013 — exposed and eroded by ocean water in a matter of weeks. Based on the geologic setting, the researchers estimate the tracks at about 800,000 years old (making them the oldest hominid footprints yet found outside Africa), and suggest the footprints might have been left by Homo antecessor.

Nizar Ibrahim, Paul Sereno and collaborators describe the aquatic adaptations of Spinosaurus, a massive carnivorous dinosaur species first studied by Ernst Stromer around 1912. Citing the animal's tiny nostril high on the head, dense limb bones, long forelimbs and flat feet, the authors argue that the dinosaur lived a semiaquatic life.

Researchers affiliated with the Museum of Paleontlogy Egidio Feruglio announce the discovery of the biggest dinosaur yet discovered: a seven- storey-tall titanosaur from Patagonia. A few months later, an international research team names the species Dreadnoughtus schrani, and states that multiple aspects of the skeleton indicate the animal was still growing when it died.

Xiaoya Ma and coauthors describe a well preserved 520-million-year-old fossil arthropod of the species Fuxianhuia protensa. The team identifies the animal's circulatory system from dark carbon lines in the fossil. The researchers argue that this fossil preserves the oldest cardiovascular system yet known, and that complex cardiovascular systems evolved early in the Cambrian Period.

Bryan Sykes and colleagues publish their DNA analysis of 37 hair samples purported to be remains of Bigfoot or Yeti, collected from Russia, the Himalaya and the United States. They announce that two samples match the DNA of fossil polar bears, and the rest match animals such as dogs, cows, horses, raccoons, and goat-like serows.

Bhart-Anjan Bhullar, Arhat Abzhanov and colleagues announce that they have reverse engineered dinosaur snouts in chicken embryos by altering beak- building gene expressions.

Stephen Hackley publishes a review article arguing that human brains retain vestigial neural circuitry, the same circuitry that currently allows other mammals (and once allowed our ancient ancestors) to orient their ears toward novel stimuli.

William C. Campbell and Satoshi Omura share the Nobel prize in Medicine "for their discoveries concerning a novel therapy against infections caused by roundworm parasites" and Tu Youyou receives a Nobel {rize in Medicine "for her discoveries concerning a novel therapy against Malaria"

2015

Bhart-Anjan Bhullar, Arhat Abzhanov and colleagues announce that they have reverse engineered dinosaur snouts in chicken embryos by altering beak- building gene expressions.

Stephen Hackley publishes a review article arguing that human brains retain vestigial neural circuitry, the same circuitry that currently allows other mammals (and once allowed our ancient ancestors) to orient their ears toward novel stimuli.

William C. Campbell and Satoshi Omura share the Nobel prize in Medicine "for their discoveries concerning a novel therapy against infections caused by roundworm parasites" and Tu Youyou receives a Nobel {rize in Medicine "for her discoveries concerning a novel therapy against Malaria"

A team led by Sonia Harmand announces the discovery of stone tools at Lomekwi, Kenya, estimated to be 3.3 million years old, meaning older than the genus Homo. The heaviest of the tools prompt archaeologist David Braun to ask about their makers, "What the hell do these things look like if they can use 15-kilogram tools?"

After recruiting skinny spelunkers to excavate a cave he can't reach, and recruiting "early career scientists" to interpret the fossils, Lee Berger, with his coauthors, announces Homo naledi from South Africa. Berger and coauthors suggest that the hominid might be more than 2 million years old and that it might have intentionally disposed of its dead. In an accompanying commentary, Chris Stringer expresses surprise at "the apparent lack of attempts" to date the fossils.

After studying Chinle Formation rocks at Ghost Ranch, New Mexico, Jessica Whiteside and coauthors argue that weather extremes, drought and fires kept dinosaurs from dominating Earth's tropics for the first 30 million years of the Mesozoic Era.

An international research team announces that Sterkfontein Cave's "Little Foot," classified as Australopithecus prometheus, is 3.67 million years old, making the fossil older than the iconic Lucy.

An international research team describes Aegirocassis benmoulae, a 480- million-year-old arthropod similar to Anomalocaris that might have measured as much as 2 meters (6 feet) long. Found in Morocco, the fossils have been preserved in three dimensions, and indicate that the giant arthropod was a filter feeder.

Based on new specimens from Burgess Shale, Martin Smith and Jean-Bernard Caron describe the elusive head of the Cambrian animal Hallucigenia, noting that it is shaped like a spoon with "a really cheeky semicircular smile" next to multiple appendages. They also note that what had previously been mistaken for the head was at the other end of the body — "decay fluids" squeezed out of the gut during fossilization.

Caleb Brown and Donald Henderson describe Regaliceratops peterhewsi, a new species of ceratopsid dinosaur that they have nicknamed "Hellboy."

Emily Mitchell and coauthors hypothesize that Fractofusus, an Ediacaran Period rangeomorph (unlike a modern plant or animal, but big enough to leave a distinctive fossil), reproduced in two ways: by sprouting clones from its body, and by releasing propagules (akin to seeds) into the ocean water.

Fernando Novas and coauthors describe Chilesaurus diegosuarezi, a "bizarre herbivorous" theropod, i.e., a member of a group of typically carnivorous dinosaurs, from Jurassic-aged rocks in Chile. The dinosaur species is named for Diego Suárez, who found the first fossil bones in the rock formation when he was seven years old.

James Lamsdell and coauthors describe the oldest-yet-known sea scorpion (eurypterid), from 467-million-year-old rocks in Iowa. The researchers state that Pentecopterus decorahensis grew to over 5 feet long and, unlike any other arthropod known (living or extinct), radically changed limb shape during the growth process. The authors suggest that eurypterids either diversified very quickly, or originated much earlier than previously thought.

Nohemi Sala and coauthors describe a 430,000-year-old skull from Spain's Sima de los Huesos Cave bearing two fractures indicative of deadly blunt- force trauma. The authors describe the find as "the earliest evidence of lethal interpersonal violence in the hominin fossil record."

Silvia Danise and Nicholas Higgs describe trace fossils suggesting that the marine worm genus Osedax fed on the bones of Cretaceous plesiosaurs that fell to the ocean floor 100 million years ago. They hypothesize that the genus of the species Osedax mucofloris ("bone-eating snot flower" first described in 2005) ate the bones of Mesozoic marine reptiles and sea turtles before whales evolved into the worms' favorite food.

Xiaoya Ma and coauthors argue that brain tissue has been fossilized in seven specimens of the Cambrian arthropod Fuxianhuia protensa from the Chenjiang fossil beds in southwest China.

Xing Xu and colleagues describe Yi qi, a small Jurassic dinosaur with weird rod-like bones projecting from its wrists, and traces of membranes. The researchers assert that the rod-like bones might have supported membranes that might have been used in flight, but probably just gliding. They also note that the dinosaur had a relatively heavy behind and would have occasionally stalled.

A team of scientists describes Acmella nana collected from the forests of Borneo. The shells range in size from 0.60 to 0.79 millimeters, roughly 0.30 millimeters smaller than the previous tiniest-snail-species record holder identified just a month before.

Jérémie Teyssier and coauthors attribute panther chameleons' ability to quickly change color to their ability to rapidly tune a network of photonic crystals under their skin. The authors also argue that a deeper layer of larger crystals in the chameleons' skin reflects sunlight, especially in the near-infrared. In short, the crystals keep the chameleons both cool and colorful.

Nature publishes "Here Be Dragons" explaining that medieval dragons, who engaged in a centuries-long slumber encouraged by the Little Ice Age and "a bewildering lack of knights," might undergo a resurgence due to global warming since higher temperatures benefit "buccal and nasal furnaces." The article is published online on April 1 with the editorial note that "some of its content may merit a degree of scepticism."

2016

Yoshinori Ohsumi receives the Nobel prize in Medicine "for his discoveries of mechanisms for autophagy"

image A team led by Victoria McCoy publishes an analysis of Tullimonstrum gregarium (the Tully monster, originally found in 1955) concluding that the animal was a vertebrate related to lampreys. One of the paper authors, Carmen Soriano, remarks, "If you put in a box a worm, a mollusk, an arthropod and a fish, and you shake, then what you have at the end is a Tully monster."

Allen Nutman and colleagues argue that a group of metamorphic rocks from the Isua Supracrustal Belt in southwest Greenland preserve 3.7-billion- year-old stromatolites. If the claim is correct, the fossils are the oldest so far discovered, but other researchers express doubts.

Błażej Błażejowski and coauthors argue that Trimerocephalus chopini, 365-million-year-old eyeless Devonian trilobites, migrated by forming single-file lines, keeping their queues together through touch and/or chemical signals such as pungent urine.

David Norman and colleagues announce that a mineral lump found on a Sussex beach in 2004 is fossilized brain tissue from a 133-million-year-old dinosaur, perhaps an Iguanodon or related species.

Elizabeth Martin-Silverstone and coauthors describe fossil pterosaur fragments (an upper arm bone and some vertebrae) from Hornby Island, British Columbia. The researchers state that the internal structure of the humerus and the partially fused condition of the vertebrae suggest the individual was nearly full grown when it died, and had a wingspan of just 1.5 meters (5 feet). If the pterosaur was as little as the researchers suspect, then when it was perched, it would be about as short as a house cat.

Frido Welker and coauthors argue that 40,000-year-old jewelry, collected decades earlier from Arcy-sur-Cure, was made by Neanderthals. The researchers base their claim on the amino acids found in the collagen of bone fragments associated with the ancient bits of bling — amino acids indicative of Neanderthals as opposed to archaic humans.

Gerrit van den Bergh and coauthors announce the find of Homo floresiensis- like fossils from a new site on the island of Flores, about 50 miles east of the 2004 "hobbit" discovery site. The new find, including a partial mandible and some teeth, is estimated at 700,000 years old, more than half a million years older than the fossils found in 2004.

John Kappelman and colleagues claim that the Australopithecus africanus specimen Lucy fell from a tree more than 30 feet high, dying in the fall that left observable fractures in her fossil bones. The claim attracts skepticism from Donald Johanson and Tim White, members of the original Lucy discovery team.

Lida Xing and coauthors describe the feathered tail of a theropod dinosaur, perhaps a young coelurosaur. The fossil is preserved in Cretaceous amber from Myanmar (Burma).

Mary Higby Schweitzer and coauthors publish a study of medullary bone (known as a ready-to-use source of calcium for making eggshells in modern birds) in a Tyrannosaurus rex fossil. The researchers argue that the medullary tissue shows that this T. rex was not only female but also pregnant.

Mikkel Pedersen and coauthors argue that Beringia did not shed glaciers and gain vegetation early enough to support the ancestors of Clovis people, though later migrants to the Americas might have traveled that route.

Nichole Gunter and coauthors hypothesize that dung beetles probably evolved during the Cretaceous Period to eat dinosaur poo, and that "the switch in dinosaur diet to incorporate more nutritious and less fibrous angiosperm foliage provided a palatable dung source that ultimately created a new niche for diversification."

Julius Nielsen and coauthors publish an account of the longest-lived vertebrate so far discovered: a Greenland shark (Somniosus microcephalus) that ranges in age from 272 to 512 years old.

2017

Jeffrey C. Hall, Michael Rosbash and Michael W. Young share the Nobel Prize in Medicine "for their discoveries of molecular mechanisms controlling the circadian rhythm"

A Chinese-U.S. team announces the discovery of two hominid skullcaps, 105,000 to 125,000 years old, from eastern China. Although the researchers don't assign the crania to any species, some of their peers speculate that the fossils might be Denisovan.

After studying von Ebner lines (microscopic daily growth lines in teeth) from Protoceratops andrewsi and Hypacrosaurus stebingeri embryos, Gregory Erickson and coauthors argue that the dinosaurs had months-long gestation periods, developing more like slow-growing reptiles than fast-growing birds.

An international research team describes a well-preserved baby bird specimen in a 99-million-year-old piece of amber collected from Burma. The scientists classify the hatchling as a member of the enantiornithes, extinct relatives of modern birds that still had clawed wings and teeth.

An international team describes California's Cerutti Mastodon site, found in 1992. The researchers argue that the assemblage of broken mastodon bones and rocks comprises evidence of human activity. Based on measures of radioactive uranium and thorium in the bones, they argue that the site is 130,000 years old. Because this date is generally understood to precede modern Homo sapiens spreading beyond Africa, the paper suggests that Neanderthals, Denisovans or even late Homo erectus might have reached North America via the Bering Land Bridge and Pacific Coast. Nature, the paper's publisher, calls the study a "jaw-dropping claim." Parties to the announcement anticipate skepticism.

Darren Naish and Mark Witton describe a robust cervical verterbra from the Transylvanian azhdarchid pterosaur Hatzegopteryx. The researchers argue that the animal had a short, thick neck that could withstand torsion and compression, and could bear heavy loads. Considering the fossil locality (the Romanian town of Haţeg) was an island during the Cretaceous, and therefore lacked typical terrestrial predators, the authors contend that Hatzegopteryx might have occupied the top of the food chain. Witton describes these pterosaurs as "giraffe-sized, quadrupedal Panzer- storks."

Gerald Mayr and colleagues describe a 150-centimeter- (60-inch-) long, 61- million-year-old fossil penguin, almost the biggest fossil penguin ever found, and the oldest of that size. The researchers state that this fossil's differences from more primitive penguins implies that penguins arose earlier than previously thought, probably during the Mesozoic.

Thomas Hegna and coauthors describe possible eggs from a roughly 450- million-year-old pyritized trilobite, Triarthrus eatoni. The tiny eggs are clustered near the animal's head, indicating that the head was the gamete-ejection point.

(no entry for this year)

2019

(no entry for this year)

ESP Quick Facts

ESP Origins

In the early 1990's, Robert Robbins was a faculty member at Johns Hopkins, where he directed the informatics core of GDB — the human gene-mapping database of the international human genome project. To share papers with colleagues around the world, he set up a small paper-sharing section on his personal web page. This small project evolved into The Electronic Scholarly Publishing Project.

ESP Support

In 1995, Robbins became the VP/IT of the Fred Hutchinson Cancer Research Center in Seattle, WA. Soon after arriving in Seattle, Robbins secured funding, through the ELSI component of the US Human Genome Project, to create the original ESP.ORG web site, with the formal goal of providing free, world-wide access to the literature of classical genetics.

ESP Rationale

Although the methods of molecular biology can seem almost magical to the uninitiated, the original techniques of classical genetics are readily appreciated by one and all: cross individuals that differ in some inherited trait, collect all of the progeny, score their attributes, and propose mechanisms to explain the patterns of inheritance observed.

ESP Goal

In reading the early works of classical genetics, one is drawn, almost inexorably, into ever more complex models, until molecular explanations begin to seem both necessary and natural. At that point, the tools for understanding genome research are at hand. Assisting readers reach this point was the original goal of The Electronic Scholarly Publishing Project.

ESP Usage

Usage of the site grew rapidly and has remained high. Faculty began to use the site for their assigned readings. Other on-line publishers, ranging from The New York Times to Nature referenced ESP materials in their own publications. Nobel laureates (e.g., Joshua Lederberg) regularly used the site and even wrote to suggest changes and improvements.

ESP Content

When the site began, no journals were making their early content available in digital format. As a result, ESP was obliged to digitize classic literature before it could be made available. For many important papers — such as Mendel's original paper or the first genetic map — ESP had to produce entirely new typeset versions of the works, if they were to be available in a high-quality format.

ESP Help

Early support from the DOE component of the Human Genome Project was critically important for getting the ESP project on a firm foundation. Since that funding ended (nearly 20 years ago), the project has been operated as a purely volunteer effort. Anyone wishing to assist in these efforts should send an email to Robbins.

ESP Plans

With the development of methods for adding typeset side notes to PDF files, the ESP project now plans to add annotated versions of some classical papers to its holdings. We also plan to add new reference and pedagogical material. We have already started providing regularly updated, comprehensive bibliographies to the ESP.ORG site.

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