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.

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.

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.

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.

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.

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.

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.

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.

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.

Mary Leakey finds hominid skull belonging to Paranthropus boisei.