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Evolution of Evolution — Text-only | Flash Special Report
Timeline

1543
ASTRONOMY: Sun Recognized As Center of Solar System
Nicolaus Copernicus publishes “De revolutionibus orbium coelestium” (On the Revolutions of the Heavenly Spheres), the first scientific treatise supporting the idea that the sun is at the center of the solar system.

1572
ASTRONOMY: Unchanging Heavens Challenged

Tycho Brahe determines that the nova of 1572 shows no parallax and therefore must be in the realm of the fixed stars, challenging the accepted view that the heavens were unchanging. His observations later influence Johannes Kepler's discovery of the laws of planetary motion.

1603
ASTRONOMY: Laws of Planetary Motion Discovered

From 1603 to 1605, Johannes Kepler discovers the three laws of planetary motion: 1) The Law of Ellipses, 2) The Equal Areas Law, and 3) The Harmonic Law.

1609
ASTRONOMY: Newly Discovered Telescope Used by Galileo

Galileo Galilei turns the newly discovered telescope to the sky. Within a year, he discovers lunar craters and mountains, the phases of Venus, sunspots, the rotation of the sun, and the satellites of Jupiter.

1633
ASTRONOMY: Galileo Sentenced to House Arrest

Galileo Galilei is sentenced to house arrest by the Inquisition for heresy for advancing the Copernican model of planetary motion, which argues the sun, not the Earth, is at the center of the solar system.

1669
GEOSCIENCES: Land Formation Explained by Geological Phases

Nils Steensen, known as Steno, explains how land acquired its current conformation. He argues that marine fossils indicate a former sea bed, which was violently uplifted, and, afterward, undermined by subterranean forces, causing the strata to breakup, become eroded and, in due course, form another sea bed.

1689
ASTRONOMY: Principia Mathematica Published

Isaac Newton publishes “Principia Mathematica,” which describes the physical laws that govern the motions of planets.

1718
ASTRONOMY: Position of Stars Found to Change

Using past measurements and his own observations, Edmond Halley discovers that stars change their positions over time.

1728
ASTRONOMY: Stellar Aberration Discovered

James Bradley discovers stellar aberration. This is the first proof that the Earth moves.

1770
GEOSCIENCES: Fossilized Mosasaur Bones Found

The fossilized bones of a huge animal scientifically described in 1795 by Georges Cuvier and later officially named a Mosasaur in 1822, are found in a quarry near Maastricht in the Netherlands.

1772
POLAR SCIENCES: Geographic Distribution of Organisms Studied

Johann Forster sails to the Antarctic with James Cook. His voyage around the world includes studies of the geographic distribution of organisms.

1775
ANTHROPOLOGY: Physical Anthropology Begins

Johann Friedrich Blumenbach publishes “de Generis Humani Varietate Nativa,” which marks the beginning of physical anthropology.

1791
ASTRONOMY: Universe Described As Expanding and Contracting

Charles Darwin’s grandfather, Erasmus Darwin, pens the first description of a cyclical expanding and contracting universe.

1799
GEOSCIENCES: World's First Geologic Map

William Smith maps rock formations near Bath, England, making the world's first geologic map.

1804
GEOSCIENCES: Fossils Said to Be Remains of Noah’s Flood

In “Organic Remains of a Forme r World,” James Parkinson says fossils are the remains of Noah’s Flood. In the next two volumes, he argues fossils are the remains of a world before people.

1809
DARWIN: Darwin Born

Charles Robert Darwin is born Feb. 12, 1809, in Shrewsbury, Shropshire, England, on the same day as Abraham Lincoln.

1809
BIOLOGY: Evolution Argued by Jean-Baptiste Lamarck

Jean-Baptiste Monet de Lamarck, the first important proponent of evolution, states in “Philosophy Zoologique,” that heritable changes in 'habits,' or behavior, could be brought about by the environment, and that the use and disuse of parts could lead to the production of new organs and the modification of old ones.

1811
GEOSCIENCES: Reptile Resembling Fish and Dolphins Found

Mary Anning discovers the fossilized remains of an ichthyosaur at Lyme Regis, Dorset, England. Ichthyosaurs are giant marine reptiles that resembled fish and dolphins.

1812
GEOSCIENCES: Fossils Said to Occur in Chronological Order

Paleontologist Georges Cuvier argues the distribution of fossils in the rock record proves fossils occur in the chronological order of creation: fish, amphibians, reptiles and mammals. Cuvier supports the idea of a fixed number of species.

1817
DARWIN: Mother Dies

His mother, Susannah, dies. Darwin is eight years old.

1818
ANTHROPOLOGY: Natural Selection Linked to Humans

William Charles Wells conveys his principle of natural selection among human populations, suggesting that African populations are selected for their relative resistance to local diseases.

1818
BIOLOGY: ‘Homologous Parts’ — Natural Selection Among Humans

Étienne Geoffrey Saint-Hilaire develops the idea of ‘homologous parts,’ arguing parts such as a bat’s wing and a man’s arm have the same evolutionary origin, but serve different functions.. Also, W.C. Wells argues for natural selection among human populations, suggesting African populations are selected for their relative resistance to local diseases.

1818-1824
POLAR SCIENCES: Red Snow Studied

The John Ross and John Franklin expeditions return from the Canadian Arctic with “red snow”—the first microbiological study in the polar regions.

1820
BIOLOGY: Gradual Development From Matter Described

Jean-Baptiste Lamarck describes the origin of living things as a process of gradual development from matter.

1820
POLAR SCIENCES: Books on Arctic Environments Published

William Scoresby Jr., publishes several books from 1820 to 1823, describing Arctic environments, whaling and whale biology, and several new Arctic animal species.

1821
GEOSCIENCES: Plesiosaur Skeleton Found

Mary Anning discovers the world's first Plesiosaur skeleton at Lyme Regis, Dorset, England.

1823
GEOSCIENCES: Proof Man Lived With Woolly Mammoth

Human bones are found with those of a woolly mammoth at Paviland Cave on the Gower peninsula, Wales, proving that the two lived on Earth at the same time.

1825
DARWIN: Darwin Studies Medicine

Darwin enrolls at the University of Edinburgh to study medicine, but he is not interested in his studies.

1828
DARWIN: Darwin Studies Theology

Darwin enrolls at Cambridge University to study theology, but is happier collecting beetles.

1829
GEOSCIENCES: Constancy of Change Argued By Lyell

Geologist Charles Lyell argues that the causes of change remain constant, and those causes “must forever produce an endless variety of effects, both in the animate and inanimate world.” Lyell’s work is thought to have paved the way for Darwin’s “On the Origin of Species.”

1830
GEOSCIENCES: Principles of Geology Published

Charles Lyell publishes “Principles of Geology.” Charles Darwin later takes the book with him aboard the HMS Beagle, a trip that helps form his ideas about evolution.

1831
POLAR SCIENCES: Magnetic North Pole Reached

James Clark Ross is the first person to reach the magnetic North Pole.

1831
DARWIN: HMS Beagle: Darwin’s First Examination of Evolution

Darwin begins a five-year voyage on the HMS Beagle. He considers differences among mockingbirds in the Galapagos Islands, his first examination of the evolution of species. His trip around the world lasts five years.

1834
DARWIN: Term “Scientist” Coined

William Whewell coins the term “scientist.” Whewell is one of the tutors at the University of Cambridge whom Darwin meets during his education there.

1836
DARWIN: Beagle Fossils Organized

Darwin returns to London and starts organizing the specimens and fossils collected during his voyage on the HMS Beagle.

1837
DARWIN: Darwin Draws Evolutionary Tree

Darwin draws a simple evolutionary tree in one of his notebooks below the words, “I think.” The tree is an analogy representing common descent of all species.

1837
ASTRONOMY: Stellar Parallaxes Measured

Friedrich Struve (1837), Friedrich Bessel (1838) and Thomas Henderson (1839) create detailed measurements of the apparent changes in position of stellar objects due to changes in Earth’s position, leading researchers to discover that the sun is 93 million miles away, while the next nearest star is 4.37 light years away.

1837
GEOSCIENCES: Earth Said to Have Past Ice Age

Swiss-American glaciologist and geologist, Louis Agassiz, scientifically proposes that the Earth was subject to a past ice age.

1838
DARWIN: Theory of Natural Selection Developed

From 1838 to 1839, Darwin develops his theory of natural selection. He argues that favorable, inheritable traits become more common in successive generations.

1839
DARWIN: Darwin Elected Royal Society Fellow

Darwin marries his cousin Emma Wedgwood. They will have 10 children. He also becomes a Fellow of the Royal Society, where Charles becomes the third elected Darwin. His family will hold father to son elections for 201 years until the death of his grandson, Sir Charles Galton Darwin.

1841
GEOSCIENCES: Geologic Eras Proposed—“Dinosaur” Coined

William Smith’s nephew, John Phillips, formally proposes the geologic eras Paleozoic, Mesozoic and Cainozoic (Cenozoic). Also in this year, English anatomist Sir Richard Owen proposes the term Dinosauria (“terrible lizards”). He later will be an outspoken critic of Darwin’s theory of evolution by natural selection.

1841
POLAR SCIENCES: Ross Ice Shelf Discovered

James Clark Ross discovers the Ross Ice Shelf, the largest ice shelf in Antarctica—an area about the size of France.

1842
DARWIN: Darwin Sketches Theory of Evolution

Darwin writes the first sketch of his theory of evolution, which he calls transmutation. In it he notes transmutation obeys strict laws of nature. During this time, Darwin thought these "laws of nature" were set forth by God during creation. He also outlines reasons not to publish his ideas.

1843
POLAR SCIENCES: Description of Emperor Penguin Published

Joseph Dalton Hooker publishes “The Zoology of the Antarctic Voyage of HM Ships Erebus and Terror.” It includes the first definitive description of the emperor penguin.

1844
DARWIN: Secret Essay on Evolution

Darwin secretly writes an essay on evolution by natural selection and tells his wife to have it published in the event of his death. Later he writes to English botanist Joseph Dalton Hooker, telling him of his ideas about evolution, saying it is “like confessing a murder.”

1847
POLAR SCIENCES: “Flora Antarctica” Published

Joseph Dalton Hooker publishes “Flora Antarctica,” still widely used as a reference.

1848
ANTHROPOLOGY: Neanderthal Man Discovered

A lieutenant preparing an artillery battery in old Forbes quarry in Gibraltar, England, discovers a distinctive skull that scientists call Gibraltar Man. Later it comes to be called Neanderthal Man.

1855
BIOLOGY: Evolution Seen As Universal Principle

Herbert Spencer begins publishing a projected 10 volume work concerning the principles of synthetic philosophy, in which evolution is invoked as a universal principle that involves progress through stages toward greater complexity.

1856
ANTHROPOLOGY: Early Variant of Homo Sapiens Found

Fossils found at Neanderthal in the Neander Valley near Dusseldorf, Germany, are identified as an early variant of Homo sapiens.

1856
GEOSCIENCES: Theory of Multiple Creations

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

1858
DARWIN: Wallace’s Theory of Natural Selection

Alfred Russel Wallace informs Darwin that he independently arrived at a theory of natural selection nearly identical to Darwin’s. Both theories are presented to the Linnean Society of London, the world’s oldest existing biological society. Response is subdued.

1858
BIOLOGY: Theory of Evolution Presented in London

The Darwin-Wallace paper is read to the Linnean Society of London.

1858
GEOSCIENCES: First U.S. Dinosaur Skeleton Excavated

The first dinosaur skeleton, a hadrosaurus, is excavated in the United States and described by Joseph Leidy.

1859
ASTRONOMY: Origin of Species Published

“On The Origin of Species” is published. Some argue astronomers, such as Pierre-Simon de Laplace, paved the way for its acceptance with prior discussions of cosmological evolution.

1859
POLAR SCIENCES: “On The Origin of Species” Published

“On The Origin of Species” is published. Darwin’s trip to New Zealand’s Polar Regions in 1835 aboard the HMS Beagle helps shape his ideas.

1859
DARWIN: Origin of Species Published

“On The Origin of Species” is published. The initial printing of 1,250 copies nearly sells out in a day at a price of 15 shillings.

1859
ANTHROPOLOGY: “On The Origin of Species” Published

“On The Origin of Species” is published. It does not overtly mention the evolution of man.

1859
BIOLOGY: “On The Origin of Species” Published

“On The Origin of Species” is published. It forever changes how the world views living organisms.

1859
GEOSCIENCES: “On The Origin of Species” Published

“On The Origin of Species” is published. Darwin, an experienced geologist and secretary of the London Geological Society from 1838 to 1841, devotes a large part of it to geological evidence.

1860
DARWIN: Darwin’s Theory Attacked

Samuel Wilberforce, a bishop in the Church of England, attacks Darwin’s theory at a meeting of the British Association for the Advancement of Science. Biologist Thomas Huxley, known as “Darwin’s Bulldog,” and Joseph Hooker defend Darwin’s work.

1861
GEOSCIENCES: Removal of "Creation" Date From Bible Proposed

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

1862
ASTRONOMY: Earth and Sun Said to Be Cooling

Physicist Lord Kelvin asserts that the Earth and sun are cooling from their initial formation, between 20 and 400 million years ago.

1866
ANTHROPOLOGY: Human Family Tree Proposed

Ernst Haeckel proposes a hypothetical family tree that begins with a speechless ape-man and leads to Homo sapiens. His tree incorporates several principles of Darwinian evolution.

1866
BIOLOGY: Foundational Work for Biology Published

Gregor Mendel publishes “Experiments in Plant Hybridization.” This is a foundational work for all of biology.

1867
DARWIN: Darwin Struggles With Theory of Acquired Characters

Darwin uses Jean-Baptiste Lamarck's theory of acquired characters to explain why variation would not be eliminated by inheritance from a blend of the parents. Lamarck's theory is dismissed only in 1900 with the rediscovery of Johann Gregor Mendel’s idea of unit characters.

1867
BIOLOGY: Portions of ‘Origin’ Rewritten

Fleeming Jenkin’s review of “On The Origin of Species” argues variation would be eliminated by inheritance from a blend of the parents. The criticism causes Darwin, in subsequent editions, to resurrect Lamarck’s theory of acquired characters. Lamarck's theory is put aside only in 1900, when Mendel’s idea of unit characters is rediscovered.

1868
ANTHROPOLOGY: Humanity Divided—Cro-magnon Man Discovered

Ernst Haeckel subdivides humanity into 12 species. He asserts evolution consists of 22 phases, the 21st being the "missing link" between apes and humans. Also, French geologist, Louis Lartet, discovers ancient skeletons that he calls Cro-magnon Man, who is thought to be more evolved than Neanderthal Man.

1869
ASTRONOMY: Journal Nature First Published

English scientist and astronomer Joseph Lockyer starts the scientific journal Nature.

1869
BIOLOGY: DNA Isolated

Swiss physician Friedrich Miescher isolates DNA after discovering a microscopic substance in the pus of discarded surgical bandages.

1871
DARWIN: “The Descent of Man” Published

Darwin publicizes “The Descent of Man.” It overtly applies evolution to humans and shocks Darwin's opponents.

1871
BIOLOGY: Sudden Arise of Species Argued

St. George Mivart argues that species arise suddenly with large-scale changes already intact. This is in sharp contrast to Darwin, who proposed inheritance by blending, meaning that variation would be sustained by an extremely high mutation rate.

1871
ANTHROPOLOGY: “The Descent of Man” Published

Darwin publishes “The Descent of Man.” He overtly applies evolution to humans and postulates Africa as the site of the earliest human ancestors.

1871
GEOSCIENCES: Lord Kelvin Suggests Life From Meteorite

Mathematical physicist and engineer William Thomson, aka Lord Kelvin, suggests that “the germs of life might have been brought to the earth by some meteorite.” The idea still enjoys support.

1872
DARWIN: Boltzmann Supports Theory of Evolution

Ludwig Boltzmann argues the spontaneous increase in decay or disorder predicted by the second law of thermodynamics is not germane to Darwin’s theory of evolution because it affects paths followed by large populations of objects, but may or may not affect individual objects wherein evolutionary change takes place.

1873
BIOLOGY: Effects on Isolated Groups Emphasized

Moritz Wagner emphasizes the effects of different environments on isolated groups of animals.

1875
BIOLOGY: Heredity, Environment, and Behavioral Traits Emphasized

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

1876
BIOLOGY: Special Contribution to Evolution Published

Wallace publishes his special contribution to the study of evolution, “The Geography of Animal Distribution.”

1876
POLAR SCIENCES: Study of Plants and Climate Published

H.W. Fielden and H.C. Hart publish “The Greenland Manual,” which includes the study of plants and their relation to climate.

1879
GEOSCIENCES: U.S. Geological Survey Established

United States President Rutherford B. Hayes establishes The United States Geological Survey within the Department of the Interior to classify the public lands, and examine the geological structure, mineral resources and products of the national domain.

1882
DARWIN: Darwin Dies

Charles Darwin dies on April 19, 1882, in the village of Downe in the London Borough of Bromley, England, where he lived for 40 years. Darwin was given a state funeral and buried in Westminster Abbey, a few feet away from Sir Isaac Newton.

1882
GEOSCIENCES: Darwin Publishes Final Letter to Nature

Charles Darwin publishes his final letter in the journal Nature, on the dispersal of freshwater bivalves. His obituary appears the same month.

1883
BIOLOGY: Germ-line Theory Refutes Acquired Characters

August Weismann refutes Jean-Baptiste Monet de Lamarck's theory that acquired characters can be inherited. His 'germ-line theory’ makes it possible to understand the genetics of animals, but not plants. As a result, it is believed that evolution can be understood without understanding how organisms develop.

1883
ANTHROPOLOGY: Human Psychology Compared to Animals

George John Romanes publishes “Mental Evolution in Animals,” the first modern text comparing the psychology of humans and animals in objective terms.

1883
GEOSCIENCES: Cryptozoon Defined

James Hall defines cabbage-like, reef-forming fossil algae found in oceans as “cryptozoon.” Cryptozoon will be important to understanding molecular evolution and the evolutionary history of life.

1886
ANTHROPOLOGY: Neanderthal Skeletons Not Modern Humans

Two complete Neanderthal skeletons are found in a cave near Spy, Belgium. The skeletons challenge the idea that Neanderthals are modern humans.

1891
ANTHROPOLOGY: Java Man Discovered

Eugene Dubois discovers, on the island of Java, remains of what he calls "a species in between humans and apes." He names his find Pithecanthropus erectus, or Java Man. Today, similar finds are classified as Homo erectus.

1897
ASTRONOMY: Sun Said to Be 20 Million Years Old

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. The lecture represents a further refining of his earlier finding.

1897
POLAR SCIENCES: Small Mites Discovered in Antarctica

Discovery of small mites and collumbola, abundant among the mosses and lichens in Antarctica.

1900
BIOLOGY: Mendel’s Work on Inheritance Rediscovered

Hugo de Vries, Carl Correns and Erik von Tschermak rediscover Gregor Mendel’s genetics work on inheritance traits in pea plants. Mendel’s work shows that the inheritance of traits follows particular laws, which are later named after him.

1901
BIOLOGY: Saltation Theory Developed

Hugo de Vries discovers a primrose that leads to the Saltation Theory, which says "new species" suddenly spring into existence through "mutation," rather than by imperceptible, gradual changes, as Darwin had proposed. In 1914, Edward Jefferies discovers the primrose was a new variety, not a new species.

1901
POLAR SCIENCES: Antarctic Sea Birds Studied

From 1901 to 1912, Edward Wilson studies the characteristics, life histories and behavior of Antarctic sea birds on both of Captain Robert Falcon Scott’s two expeditions to the Antarctic region.

1902
GEOSCIENCES: Tyrannosaurus Rex Discovered

Barnum Brown of the American Museum of Natural History discovers Tyrannosaurus rex. It’s later described and named by Henry Fairfield Osborn in 1905.

1905
ASTRONOMY: Special Theory of Relativity Proposed

Albert Einstein publishes "On the Electrodynamics of Moving Bodies," in which he proposes the Special Theory of Relativity, arguing that space and time are not separate continuums.

1907
GEOSCIENCES: First Radiometric Dating Techniques

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

1908
POLAR SCIENCES: North Pole Claimed by Cook

American explorer Frederick Albert Cook claims to reach the North Pole. His claims are disputed.

1909
BIOLOGY: Evolutionary Relationships Among Species Studied

Edward Tyson Reichert begins studying evolutionary relationships among species using differences in their hemoglobin molecules.

1909
POLAR SCIENCES: North Pole Claimed by Peary

American Navy engineer Robert Edwin Peary claims to reach the North Pole. His claims are disputed.

1910
POLAR SCIENCES: Fossilized Glossopteris Discovered

Between 1910 and 1913, members of Captain Robert Falcon Scott’s Terra Nova Expedition discover fossilized Glossopteris leaves belonging to an order of seed ferns in the Antarctic region, an important link with other continents that once formed a supercontinent called Gondwana, originally called Gondwanaland.

1911
ASTRONOMY: Color or Spectral Class of Stars Plotted

Ejnar Hertzsprung published graphs plotting color, or spectral class, against the absolute magnitude of stars.

1911
POLAR SCIENCES: Geographic South Pole Reached

Norwegian Roald Amundsen and his party are first to reach the Geographic South Pole. Amundsen names the plateau surrounding the Pole Haakon VII's Vidde, in honour of King Haakon VII of Norway.

1912
ANTHROPOLOGY: Piltdown Man Found

Parts of a jaw and skull found in England are dubbed Piltdown Man. The report of a dentist, in 1916, who said someone had filed down the teeth, is ignored. In 1953 Piltdown Man is shown to be a hoax.

1912
GEOSCIENCES: Continental Drift Proposed

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

1912
ASTRONOMY: Redshift Discovered

Vesto Slipher is the first to observe the shift of spectral lines of galaxies, also known as redshift, which will be important for later discoveries regarding an expanding universe.

1913
ASTRONOMY: Hertzsprung-Russell Diagram

Henry Norris Russell presents graphs similar to Ejnar Hertzsprung’s graphs. These are now called Hertzsprung-Russell, or HR, diagrams and are the basis of the theory of stellar evolution. Russell also suggested that nuclear energy is generated inside stars when they reach a critical temperature.

1913
ANTHROPOLOGY: Neanderthal Man Reconstructed

Marcelin Boule reconstructs the Le Chapelle Neanderthal. He misdiagnoses certain conditions of the skeleton, reconstructing it with a bent, stooped knee posture and ambling walk.

1915
ASTRONOMY: General Theory of Relativity Published

Albert Einstein publishes the “General Theory of Relativity,” which relates gravity to space-time. It is the current description of gravity in modern physics.

1917
ASTRONOMY: Evolution of Gaseous Stars Described

James Hopwood Jeans describes a general theory of the configuration of equilibrium of compressible and non-homogeneous masses of astronomical matter, enabling him to explain the behavior of certain nebulae and describe the evolution of gaseous stars.

1917
ANTHROPOLOGY: Nebraska Man Found, Scopes Monkey Trial Evidence

Geologist Harold Cook finds a single molar tooth in Nebraska which later is named Hesperopithecus, or "Nebraska Man." An "apeman" picture based on the tooth becomes key evidence in the 1925 Scopes Monkey trial. In 1928, paleontologists discover the rest of the skeleton. The tooth belongs to an extinct pig.

1917
BIOLOGY: Alternative to Survival of the Fittest Argued

D'Arcy Thompson, in “On Growth and Form,” takes basic body plans and changes their size and position relative to one another in geometric ways, showing how evolution might have occurred. He argues biologists overemphasize survival of the fittest. He argues for structuralism as an alternative to survival of the fittest.

1918
ASTRONOMY: Novae Described—Henry Draper Catalogue Published

Novae are shown to be preexisting faint stars which brightened suddenly, rather than new stars coming into existence. Also, Annie Jump Cannon publishes “The Henry Draper Catalogue” of stars. It gives spectroscopic classifications for 225,300 stars.

1918
BIOLOGY: Darwinian and Mendelian Views Reconciled

Ronald A. Fisher publishes “The Correlation Between Relatives on the Supposition of Mendelian Inheritance,” which leads the way to reconciling Darwinian and Mendelian views of evolution.

1921
GEOSCIENCES: Mountain Building Proposed Cause for Dinosaur Extinction

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

1922
ASTRONOMY: Einstein’s Equations Could Describe Expanding Universe

Russian mathematician and meteorologist Aleksandr Friedmann asserts that Einstein’s equations could describe an expanding universe.

1923
ASTRONOMY: Space-based Telescopes Proposed

German scientist Hermann Oberth, along with Robert Goddard and Konstantin Tsiolkovsky, considered the three fathers of modern rocketry, propose propelling a telescope into Earth orbit by a rocket.

1924
ASTRONOMY: Mass-luminosity Relationship Discovered

Arthur Eddington discovers the relationship between a star’s intrinsic brightness and its mass, the so-called mass-luminosity relationship.

1925
ANTHROPOLOGY: Description of Australopithecus Published

Raymond Dart publishes the first description of the new genus Australopithecus based on the Taung child skull found in 1924 in Buxton Limeworks in South Africa. Identification of this ape-man as a human ancestor is skeptically received, particularly since its small brain and large teeth are opposite of Piltdown Man.

1926
ASTRONOMY: A Key to Stellar Evolution Discovered

In 1926 and 1927, Hermann Vogt and Henry Norris Russell independently discover a star’s mass and its chemical composition determine its structure. Their findings are important for determining a star’s life-history, a chief aspect of stellar evolution.

1926
POLAR SCIENCES: North Pole Sighted—Arctic Ecology Described

Norwegian Roald Amundsen makes the first undisputed sighting of the North Pole from the airship Norge and Alwin Pedersen publishes the first detailed accounts of the ecology of Arctic birds and mammals in Northeast Greenland, where he has spent several years working with trappers. He publishes several accounts until 1962.

1928
ANTHROPOLOGY: Milestone Book: “The Antiquity of Man” Published

Sir Arthur Keith develops his version of the human family tree. Keith, one of Britain’s most respected researchers is taken in by the Piltdown Man hoax. His book, “The Antiquity of Man,” is a milestone in evolutionary research.

1929
ASTRONOMY: Expanding Universe Discovered—Energy Source for Stars

Edwin Powell Hubble discovers that “red shift” increases with distance, showing that galaxies are moving apart with a speed that is proportional to their distance. The finding is further evidence the universe is expanding. George Gamow also speculates that hydrogen fusion is the energy source for stars.

1929
GEOSCIENCES: Cause for Dinosaur Extinction—Transitional Animal Found

Paleobiologist Alexander Audova publishes a paper rejecting racial senility as the cause of dinosaur extinction instead pointing to environmental change. Also beginning this year through 1934, expeditions led by Gunnar Save-Soderbergh find remains of a transitional animal between fish and amphibian on Greenland. The species is named Ichthyostega soderberghi.

1930
BIOLOGY: Clandestine Evolution—Genetical Theory of Natural Selection

Gavin de Beer theorizes an organism’s anatomy develops through acceleration and retardation. His clandestine evolution explains sudden changes in the fossil record which are apparently at odds with Darwin's gradualist theory of evolution. R.A. Fisher publishes, “The Genetical Theory of Natural Selection,” which reconciles Mendelian genetics with natural selection.

1930
ASTRONOMY: Reliable Age for the Universe

Astrophysicist Subrahmanyan Chandrasekhar describes the maximum mass of a white dwarf star above which the star will collapse into a neutron star or a black hole. “Chandrasekhar's limit” later is used to show the universe is speeding up, not slowing down as expected. Chandrasekhar receives the Nobel Prize in 1983.

1931
BIOLOGY: 'Random Drift’ Significant Factor in Evolution

Sewall Wright concludes that 'random drift,' or chance fluctuation of gene populations, is a significant factor in evolution. His works contribute to the Modern Synthesis, the combining of natural selection and Mendelian genetics.

1933
BIOLOGY: Genetics, Development and Evolution Integrated

Richard Goldschmidt concludes evolution is the result of sudden changes by successful mutations that act on early embryological processes. Goldschmidt is considered the first to integrate genetics, development and evolution.

1933
POLAR SCIENCES: Most Southerly Plants Found

The second Byrd Expedition (1933-1935) finds lichens, a type of fungus, half way up the Scott Glacier. They are the most southerly plants yet found.

1936
ANTHROPOLOGY: Adult Australopithecus Fossils Discovered

Robert Broom discovers the first adult Australopithecus at Sterkfontein and establishes it as an early hominid. Over the next 10 years, more fossils representing two separate species Australopithecine are found at Kromdrai, Swartkrans and other sites in Transvaal Province, South Africa, dating from 1.8 to 2.5 million years ago.

1938
ASTRONOMY: Energy Source for Stars Proved

Hans Bethe and colleagues publish a series of papers in a treatise called “Energy Production in Stars,” which explains all the known facts of stellar energy and proves the presence of nuclear reactions. He wins the Nobel Prize for this work in 1967.

1942
BIOLOGY: “The Modern Synthesis” Published

In “The Modern Synthesis,” Julian Huxley brings together ideas from several biological specialties to form a unified theory of evolution.

1942
GEOSCIENCES: Contributions to Neo-Darwinian Synthesis

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.

1944
BIOLOGY: Living Organisms Said to Pass Along Information

Erwin Schrödinger publishes “What is Life?” In it he argues that living organisms store and pass along information. This book will inspire James Watson, Francis Crick and Maurice Wilkins, who will share the Nobel Prize for discovering, in 1953, the structure of DNA.

1947
ANTHROPOLOGY: “Up From The Ape” Published, Includes Piltdown Man

Harvard anthropology professor Earnest Hooton publishes “Up From The Ape,” a treatise on human evolution. His evolution tree includes the Piltdown Man on the main stem leading to modern humans.

1947
GEOSCIENCES: Carbon-14 Dating

Willard Libby introduces carbon-14 dating.

1948
ASTRONOMY: Steady State Cosmology Proposed—Hale Telescope.

Steady State Cosmology, which hypothesizes continuous creation of matter, is proposed by Hermann Bondi, Thomas Gold and Fred Hoyle. The Palomar Observatory in San Diego County, Calif., also opens this year. Its 200 inch Hale telescope helps understand distant galaxies and quasars. Edwin Hubble is first to use the telescope.

1948
BIOLOGY: Transposition of Mobile Genetic Elements Discovered

Barbara McClintock discovers the transposition of mobile genetic elements, i.e., they change position on the chromosome. She receives a Nobel Prize for her work in 1983.

1950
ASTRONOMY: Term "Big Bang'' Coined

British astronomer Fred Hoyle coins the term "big bang'' to describe the theory that the universe was born at one moment, about ten thousand million years ago and its galaxies are still expanding. Hoyle meant the term as a rebuke, arguing instead that the universe is in a steady state.

1951
ANTHROPOLOGY: Physical Anthropology Redefined

Sherwood Washburn publishes “The New Physical Anthropology,” emphasizing multidisciplinary and integrative approaches to understanding human evolution through genetics, behavioral and anatomical studies of humans and nonhuman primates in both the laboratory and field.

1953
ANTHROPOLOGY: Use of Fire at Kalambo Falls, Zambia

J. Desmond Clark finds evidence of fire use at an archeological site in Kalambo Falls, Zambia. Use of the site dates from 300,000 years to 250 A.D.

1953
BIOLOGY: First Accurate Model of DNA Published

James Watson, Francis Crick and Maurice Wilkins publish the first accurate model of DNA structure in the journal Nature. They were awarded the Nobel Prize for this work in 1962.

1956
GEOSCIENCES: Meteorite Impact Proposed Cause For Dinosaur Extinction

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.

1957
ASTRONOMY: Origin of Elements Proposed

William Fowler, Margret Burbridge, Geoffrey Burbridge and Fred Hoyle explain how nuclear reactions in stars convert one chemical element or isotope into another to produce the universe's existing elements. William Fowler receives the Nobel Prize for his contribution to their paper, “Synthesis of the Elements in Stars” in 1983.

1959
ANTHROPOLOGY: 1.75 Million-Year-Old Skull Found

Louis and Mary Leakey discover the skull of Zinjanthropus bosei, an early hominid dated using a potassium-argon method to 1.75 million years ago. They make the discovery at Olduvai Gorge in Tanzania. It is their first major find and the first major early hominid find in eastern Africa.

1959
POLAR SCIENCES: First Illustrated Work on Arctic Plant Life Published

Nicholas Polunin publishes the first comprehensive and illustrated “Circumpolar Arctic Flora,” his first volume in a projected series of four books dealing with the plants of the Arctic.

1960
ANTHROPOLOGY: First Species of Homo Genus Possibly Found

Louis and Mary Leakey discover Homo habilis at Olduvai Gorge in northern Tanzania. Homo habilis is arguably the first species of the genus Homo.

1960
POLAR SCIENCES: Hidden Mountain Ranges Discovered in Antarctica

Radio echo, sub-ice topography in Antarctica reveals hidden mountain ranges.

1961
BIOLOGY: Game Theory Apply to Evolutionary Biology

Richard C. Lewontin is the first to apply game theory to evolutionary biology. The application pits species against nature in seeking survival strategies.

1962
ANTHROPOLOGY: Humans and Chimpanzees Closely Related

Morris Goodman first proposes that humans and chimpanzees are more closely related than chimpanzees and gorillas based on immunochemical evidence.

1963
ASTRONOMY: Concept of Supermassive Stars — Discovery of Quasars

William Fowler and Fred Hoyle introduce the concept of supermassive stars—hypothetical stars whose mass exceeds 60 times the mass of the sun. Also, the discovery of quasars provides observational evidence that the early universe differed from the universe of today.

1964
BIOLOGY: Existence of Sterile Castes in Insects Explained

William D. Hamilton defines 'inclusive fitness' as a formal way to show that relatives have evolutionary effects on each other, as a result of shared genes. Hamilton’s idea expands Darwin's explanation of the existence of sterile castes in insects and is a foundation of sociobiology.

1964
GEOSCIENCES: Climate Linked to Evolution of Multicelluar Life

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
ASTRONOMY: Kelvin Background Radiation Discovered

Arno Penzias and Robert Wilson discover the 3 degree Kelvin background radiation, theorized as a relic of the big bang. Also called cosmic background radiation, this is radiation emitted when the universe was very hot.

1965
BIOLOGY: Molecular Sequences Said to Reveal Evolutionary Relationships

Emile Zuckerkandl and Linus Pauling argue that molecular sequences can reveal evolutionary relationships in such a way that observable characteristics and molecular functions cannot.

1966
ANTHROPOLOGY: Diversity Results From Environmental Stress

Paul T. Baker pioneeres anthropological research on human population biology viewing diversity as an adaptive response to environmental stress.

1966
BIOLOGY: Previously Unknown Levels of Genetic Variation Revealed

John Hubby and Richard Lewontin use starch gel electrophoreses to reveal previously unknown high levels of genetic variation within populations. Their work is the foundation of the field of molecular genetics.

1966
GEOSCIENCES: Reexamination of Burgess Shale Fossils

Harry Whittington begins reexamining Burgess Shale fossils originally identified by Charles Walcott, starting in 1909. During the next two decades, Whittington (with the assistance of graduate students Simon Conway Morris and *Derek Briggs) will overturn some of Walcott's theories and propose that most of the animals left no living relatives.

1966
POLAR SCIENCES: First Deep Ice Core Samples in Greenland

The first deep ice core to penetrate the total ice thickness (1387 meters) at Camp Century in northwestern Greenland, allows scientists to reconstruct global climatic history from snow sediments.

1967
ANTHROPOLOGY: Split Between Chimpanzees and Humans Proposed

Vincent Sarich and Allan Wilson publish an immunological time scale for human evolution, placing the split between chimpanzee and human at about five million years ago.

1968
BIOLOGY: Neutral Theory of Evolution Developed

Japanese biologist Motoo Kimura develops the neutral theory of evolution. The theory suggests almost all evolution at the molecular level is due to random drift. The idea contrasts with neo-Darwinians, who believe natural selection is more prominent.

1970
ASTRONOMY: Singularity Theorem Proved

Stephen Hawking proves the first of many singularity theorems that provide a set of sufficient conditions for the existence of a singularity, i.e., a point in space-time in which gravitational forces cause matter to have an infinite density and zero volume.

1970
BIOLOGY: Synthetic Theory of Evolution—Gene Duplication

Richard Lewontin argues the synthetic theory of evolution should be expanded to include multiple units of selection. Meanwhile, Susumu Ohno publishes “Evolution by Gene Duplication,” arguing that duplicated genes accumulate, then mutate to have previously nonexistent functions. Gene duplication will be seen as a major process in evolution.

1972
ANTHROPOLOGY: Theory of 'Punctuated Equilibria’ Presented

Stephen J. Gould and Niles Eldredge argue that evolution proceeds over time by 'punctuated equilibria,' or periods of inactivity punctuated by episodic events, rather than by slow gradualism. They also argue that the record of fossil remains found in ancient rock layers is in fact accurate.

1972
BIOLOGY: Theory of 'Punctuated Equilibria’ Presented

Stephen J. Gould and Niles Eldredge argue that evolution proceeds over time by 'punctuated equilibria,' or periods of inactivity punctuated by episodic events, rather than by a slow gradual process.

1972
GEOSCIENCES: ‘Punctuated Equilibria’ Proposed—Warm-blooded Dinosaurs

Stephen Jay Gould and Niles Eldredge publish their theory of punctuated equilibria, stating that evolution often occurs in short bursts, followed by long periods of stability. Also this year, Bob Bakker publishes "Anatomical and Ecological Evidence of Endothermy in Dinosaurs" in the journal Nature, arguing that dinosaurs were warm-blooded animals.

1972
POLAR SCIENCES: Work on Physiological Adaptations of Mammals Published

After 40 years of research, Laurence Irving publishes the first comprehensive work on the physiological adaptations of Arctic birds and mammals, including man.

1973
POLAR SCIENCES: Polar Bear Agreement Signed

The first circumpolar and international agreement on the conservation and management of the polar bear is signed by the United States, USSR, Denmark, Canada and Norway.

1974
ASTRONOMY: Hawking Radiation Calculated

Stephen Hawking calculates that black holes should thermally create and emit subatomic particles, known today as Hawking radiation, until they exhaust their energy and evaporate.

1974
ANTHROPOLOGY: Potential Missing Link Lucy Found

Donald Johanson recovers the skeletal remains of a female hominid dated to 2.8 million years ago. His team describes her as a new species, Australopithecus afarenis and nicknames the female hominid Lucy, a potential missing link.

1974
POLAR SCIENCES: Tundra Seen As Key to Global Warming

Tundra, areas in which tree growth is hindered by low temperatures and short growing seasons, is developed as a key subject in the emerging subject of global warming.

1975
ANTHROPOLOGY: Lucy Displayed As Common Ancestor

Lucy is displayed as the common ancestor of all later homonids in a new evolutionary tree.

1975
BIOLOGY: DNA Further Defined—Human and Chimpanzee Differences

Fredrick Sanger and colleagues develop a 'plus and minus' system to determine sequences of bases on DNA strands. Mary King and Alan Wilson publish “Evolution at Two Levels in Humans and Chimpanzees.” They propose gene regulation, rather than structural genes, is responsible for differences between humans and chimpanzees.

1975
ASTRONOMY: Very Large Array Radio Astronomy Observatory

Construction begins on the Very Large Array radio astronomy observatory, which consists of 27 independent antennas, each having a dish 25 meters in diameter. The observatory investigates radio galaxies, quasars, pulsars and supernovae. Operators also follow up a seemingly extraterrestrial 72-second signal observed by the SETI (Search for Extra-terrestrial Intelligence) project.

1978
ANTHROPOLOGY: 3.5 Million-Year-Old Hominid Footprints Found

Mary Leakey’s group uncovers a trail of 3.5 million-year-old bipedal hominid footprints left in a layer of volcanic ash in Laetoli, Tanzania.

1979
BIOLOGY: Adaptionist Theories of Evolution Challenged

Richard Lewontin and Stephen Gould take issue with the adaptionist perspective, that all traits are molded by natural selection, and parody adaptationism as “Panglossian.”

1980
ASTRONOMY: 'Inflationary' Theory of the Early Universe Proposed

Alan Guth proposes 'Inflationary' theory of the early universe. The theory proposes a period of extremely rapid, exponential, expansion of the universe during its first few moments. The theory attempts to explain several puzzles with the standard big bang theory, among them, problems of the universe's homogeneity and flatness.

1980
GEOSCIENCES: Giant Comet Theory

Luis Alvarez, Walter Alvarez, Frank Asaro and Helen Michel propose a giant comet or asteroid may have struck Earth around 65 million years ago, causing massive extinctions and enriching iridium in the Earth’s K-T layer. The theory gains support in 1991, when the Chicxulub crater is discovered in the Yucatán Peninsula.

1982
ASTRONOMY : Cosmological Model of Universe Creation Proposed

Alexander Vilenkin suggests a cosmological model in which the universe is spontaneously created from literally nothing. In Vilenkin’s model, the universe does not have a singularity at the big bang and does not require any initial or auxiliary conditions that must be satisfied.

1982
POLAR SCIENCES: Proof Antarctica and South America Were Once Connected

A fossil mammal discovered on Seymour Island proves Antarctica and South America were connected as recently as 40 million years ago.

1984
ANTHROPOLOGY: Homo ergaster Skeleton Discovered

Alan Walker and Richard Leakey discover a nearly complete skeleton of an adolescent boy described as Homo ergaster. The find is made in West Turkana, Kenya. Later, most anthropologists consider these to be Homo erectus skeletons.

1984
BIOLOGY: Study of Evolution at DNA Level Begins

Kary Mullis develops the polymerase chain reaction (PCR), which opens up evolutionary studies at the DNA level. In 1993, Mullis is awarded the Nobel Prize for this development.

1984
GEOSCIENCES: Regularly Spaced Mass Extinctions Proposed

David Raup and Jack Sepkoski publish the controversial claim that mass extinctions are regularly spaced at 26 million years.

1985
POLAR SCIENCES: Antarctic Ozone Hole Discovered

Joseph Farman, Brian Gardiner and Jonathan Shanklin discover the Antarctic ozone hole.

1986
POLAR SCIENCES: First Dinosaur Discovered in Antarctica

Eduardo Olivero and Roberto Scasso discover an armored, quadrupedal, plant-eating, late Cretaceous period dinosaur on James Ross Island. It is the first dinosaur discovered in Antarctica.

1987
ANTHROPOLOGY: DNA Traced to Common African Ancestor

Rebecca L. Cann, Mark Stoneking and Allan C. Wilson develop a genealogical tree that suggests all human mitochondrial DNA can be traced back to a common African maternal ancestor, dubbed African Eve by the press.

1987
GEOSCIENCES: Most Complete Devonian Tetrapod Discovered

Jenny Clack finds Acanthostega, the most complete Devonian tetrapod yet discovered. It has evidence of functional gills as well as legs, strongly suggesting that animals evolved legs while still living in the water.

1988
OLAR SCIENCES: Evidence of Larger Antarctic Ice Sheet Found

Seafloor drilling shows that a much larger Antarctic ice sheet existed 35 million years ago.

1989
ASTRONOMY: Reliable Age for the Universe

NASA launches the COBE satellite to study cosmological background radiation; in 2001, it launches the WMAP mission to study background microwave radiation. The missions establish a reliable age for the universe and confirm its geometry is flat. The findings garner astrophysicists John Mather and George Smoot III the Nobel Prize in 2006.

1990
ANTHROPOLOGY: Evolutionary Tree Gets New Species—Language Natural Adaptation

Researchers add Homo ergaster and Homo antecessor to the evolutionary tree. The species complicate the evolutionary tree and later are considered to be Homo erectus. Also, Steven Pinker and Paul Bloom argue that languages are naturally selected biological adaptations by Homo sapiens, not a side effect of other evolutionary forces.

1990
ASTRONOMY: Hubble Space Telescope Launched

Named after astronomer Edwin Powell Hubble, the Hubble Space Telescope is carried into orbit by the space shuttle Discovery. The telescope more accurately measures how fast the universe is expanding, helps refine its age and discovers evidence of extra-solar planets around sun-like stars.

1991
POLAR SCIENCES: Dinosaurs on Every Continent—SWEAT Hypothesis Published

The fossil of a 25-foot dinosaur, 350 miles from the South Pole proves they were on every continent. An international team lead by John Goodge publishes the SWEAT hypothesis, a theory that southwestern North America and Antarctica were once linked in a Precambrian supercontinent called Rodinia.

1992
GEOSCIENCES: Snowball Earth Theory

Joe Kirschvink publishes "Late Proterozoic Low-latitude Glaciation: The Snowball Earth," a short book section in a specialized monograph. Snowball earth hypothesizes the Earth was completely covered by ice during parts of its history. The theory attracts little attention until expanded by Paul Hoffman and his collaborators several years later.

1992
POLAR SCIENCES: Bedrock Reached by Greenland Ice Core Project

Greenland ice core project GRIP reaches bedrock and discovers Dansgaard-Oeschger events—rapid climate fluctuations occurring every ≈1470 (± 532) years throughout the last glacial period.

1993
GEOSCIENCES: Oldest Known Fossils—Oviraptor Dinosaur Found

J. William Schopf publishes a description of the oldest fossils known to science—3.5 billion-year-old Australian Apex Basalt microfossils. 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.

1994
ANTHROPOLOGY: Oldest Known Human Ancestor Discovered

Tim D. White and colleagues discover in Ethiopia, the oldest known human ancestor, Ardipithecus ramidus, dating to 4.4 million years ago.

1996
GEOSCIENCES: First Feathered Dinosaur Unveiled

At the Society of Vertebrate Paleontology's annual meeting, Chen Pei Ji unveils Sinosauropteryx prima from Liaoning, China. It’s the first feathered dinosaur discovered.

1996
POLAR SCIENCES: Antarctic Meteorite Confirmed From Mars

A meteorite collected in Antarctica is confirmed to have come from Mars and offers possible evidence for ancient primitive Martian life.

1997
ANTHROPOLOGY: Neanderthal Mitochondrial DNA Sequenced

German and American researchers led by Svante Paabo analyze DNA taken from the bone of the upper arm of the first recognized Neanderthal fossil. Studies suggest Neanderthal and modern humans developed separately and did not form a single, large interbreeding population.

1998
ASTRONOMY: Dark Energy Theorized

Two groups working independently unexpectedly discover the expansion of the universe is accelerating. This leads to a variety of exotic explanations lumped under the label Dark Energy.

1998
GEOSCIENCES: Snowball Earth Theory Expanded

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.

1999
POLAR SCIENCES: New Fish Species—Antarctic Ice Cap Microorganisms

Four new fish species are found in Antarctic waters, giving biologists new insights into the processes of evolution in ecological niches. Research shows that microorganisms can survive in subglacial Lake Vostok, thousands of meters below the Antarctic ice cap.

2000
POLAR SCIENCES: Research: Microbes Can Survive Extremes of South Pole

Evidence is discovered of microbes that can survive the extremes of darkness, cold and ultraviolet radiation at the South Pole.

2001
ANTHROPOLOGY: Kenyanthropus Platyops Discovered

Meave Leakey announces the discovery of a 3.5 million-year-old fossil, Kenyanthropus platyops. She believes the fossil may represent a new branch of the early human evolutionary tree. However, some anthropologists argue that the specimen is so distorted it cannot be properly assessed and it may not represent a valid evolutionary group.

2001
ASTRONOMY: Stars Found 13.4 Billion Light Years Away

Richard Ellis, Michael R. Santos, Jean-Paul Kneib and Konrad Kuijken discover the star cluster Abell 2218 about 13.4 billion light years from Earth. The age of the cluster suggests an age when the universe was several hundred times denser than today.

2001
BIOLOGY: First Draft of the Human Genome Published

A first draft of the human genome is published. This has been followed by the publication of the genome of many species, including NSF-funded projects such as the Arabidopsis genome, many plant genomes and microbial genomes.

2003
GEOSCIENCES: Antarctic Dinosaurs Found—Egg-laying T. Rex Found

Separate teams find two new Antarctic dinosaurs in one week. One appears to be a Jurassic sauropod, the other a Cretaceous theropod. Also, Mary Schweizer and John Horner find a Tyrannosaurus rex fossil that yields evidence of blood vessels and blood cells. It proves to be an egg-laying female.

2004
ANTHROPOLOGY: Earliest Anatomically, Near-modern Human Found

Tim D. White, Berhane Asfaw and colleagues publish the earliest anatomically near-modern human, Homo sapiens idaltu, from Herto, Ethiopia, dated to 155,000 years ago, found with stone tools and butchered hippos.

2004
GEOSCIENCES: New Period Added to Geologic Timescale

The International Union of Geological Sciences adds the Ediacaran period to the earth's geologic timescale, ranging from about 600 million years ago to 542 million years ago. It's the first new geologic period designated in 120 years.

2006
ANTHROPOLOGY: 4.1 Million Year Old Australopithecus Anamensis Skeletons Announced

Tim D. White, Gen Sewa, and Berhane Asfaw announce the discovery of at least eight Australopithecus anamensis skeletons dated 4.2 million years ago and possibly intermediate between ardipithicus and Lucy..

2006
GEOSCIENCES : Mammal Mix Found—Mammals Flew Before Birds

Luo Zhe-Xi and Qiang Li describe a Jurassic mammal that looks like a mix between a beaver, otter and platypus, pushing back mammalian adaptation to aquatic lifestyles by 100 million years. Jin Meng and collaborators describe a Mesozoic gliding mammal that pushes back mammalian flight by 70 million years.

2007
BIOLOGY: Faster, Less Expensive Sequencing Technologies Developed

New, faster and less expensive sequencing technologies become available, putting the sequencing of many genomes within reach, and vastly broadening the opportunities for studies of evolution.