Timeline of the evolutionary history of life

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The timeline of the evolutionary history of life represents the current scientific theory outlining the major events during the development of life on planet Earth. Dates in this article are consensus estimates based on scientific evidence, mainly fossils.


In biology, evolution is any change across successive generations in the heritable characteristics of biological populations. Evolutionary processes give rise to diversity at every level of biological organization, from kingdoms to species, and individual organisms and molecules, such as DNA and proteins. The similarities between all present day organisms imply a common ancestor from which all known species, living and extinct, have diverged. More than 99 percent of all species that ever lived (over five billion) [1] are estimated to be extinct. [2] [3] Estimates on the number of Earth's current species range from 10 million to 14 million, [4] with about 1.2 million or 14% documented, the rest not yet described. [5] However, a 2016 report estimates an additional 1 trillion microbial species, with only 0.001% described. [6]

There has been controversy between more traditional views of steadily increasing biodiversity, and a newer view of cycles of annihilation and diversification, so that certain past times, such as the Cambrian explosion, experienced maximums of diversity followed by sharp winnowing. [7] [8]


Visual representation of the history of life on Earth as a spiral Geological time spiral.png
Visual representation of the history of life on Earth as a spiral

Species go extinct constantly as environments change, as organisms compete for environmental niches, and as genetic mutation leads to the rise of new species from older ones. At long irregular intervals, Earth's biosphere suffers a catastrophic die-off, a mass extinction, [9] often comprising an accumulation of smaller extinction events over a relatively brief period. [10]

The first known mass extinction was the Great Oxidation Event 2.4 billion years ago, which killed most of the planet's obligate anaerobes. Researchers have identified five other major extinction events in Earth's history, with estimated losses below: [11]

Smaller extinction events have occurred in the periods between, with some dividing geologic time periods and epochs. The Holocene extinction event is currently under way. [12]

Factors in mass extinctions include continental drift, changes in atmospheric and marine chemistry, volcanism and other aspects of mountain formation, changes in glaciation, changes in sea level, and impact events. [10]

Detailed timeline

In this timeline, Ma (for megaannum) means "million years ago," ka (for kiloannum) means "thousand years ago," and ya means "years ago."

Hadean Eon

Moon FullMoon2010.jpg

4540 Ma – 4000 Ma

4540 Ma Planet Earth forms from the accretion disc revolving around the young Sun, perhaps preceded by formation of organic compounds necessary for life in the surrounding protoplanetary disk of cosmic dust. [13] [14]
4510 MaAccording to the giant-impact hypothesis, the Moon originated when Earth and the hypothesized planet Theia collided, sending into orbit myriad moonlets which eventually coalesced into our single Moon. [15] [16] The Moon's gravitational pull stabilised Earth's fluctuating axis of rotation, setting up regular climatic conditions favoring abiogenesis. [17]
4404 MaEvidence of the first liquid water on Earth which were found in the oldest known zircon crystals. [18]
4280–3770 Ma Earliest possible appearance of life on Earth. [19] [20] [21] [22]

Archean Eon

Fragment of the Acasta Gneiss exhibited at the Museum of Natural History in Vienna Acasta gneiss.jpg
Fragment of the Acasta Gneiss exhibited at the Museum of Natural History in Vienna
The cyanobacterial-algal mat, salty lake on the White Sea seaside Cyanobacterial-algal mat.jpg
The cyanobacterial-algal mat, salty lake on the White Sea seaside
Halobacterium sp. strain NRC-1 Halobacteria.jpg
Halobacterium sp. strain NRC-1

4000 Ma 2500 Ma

4100 MaEarliest possible preservation of biogenic carbon. [23] [24]
4100–3800 Ma Late Heavy Bombardment (LHB): extended barrage by meteoroids impacting the inner planets. Thermal flux from widespread hydrothermal activity during the LHB may have aided abiogenesis and life's early diversification. [25] Possible remains of biotic life were found in 4.1 billion-year-old rocks in Western Australia. [26] [27] Probable origin of life.
4000 MaFormation of a greenstone belt of the Acasta Gneiss of the Slave craton in northwest Canada - the oldest known rock belt. [28]
3900–2500 Ma Cells resembling prokaryotes appear. [29] These first organisms are believed[ by whom? ] to have been chemoautotrophs, using carbon dioxide as a carbon source and oxidizing inorganic materials to extract energy.
3800 MaFormation of a greenstone belt of the Isua complex in western Greenland, whose isotope frequencies suggest the presence of life. [28] The earliest evidence for life on Earth includes: 3.8 billion-year-old biogenic hematite in a banded iron formation of the Nuvvuagittuq Greenstone Belt in Canada; [30] graphite in 3.7 billion-year-old metasedimentary rocks in western Greenland; [31] and microbial mat fossils in 3.48 billion-year-old sandstone in Western Australia. [32] [33]
3800–3500 Ma Last universal common ancestor (LUCA): [34] [35] split between bacteria and archaea. [36]

Bacteria develop primitive photosynthesis, which at first did not produce oxygen. [37] These organisms exploit a proton gradient to generate adenosine triphosphate (ATP), a mechanism used by virtually all subsequent organisms. [38] [39] [40]

3000 MaPhotosynthesizing cyanobacteria using water as a reducing agent and producing oxygen as a waste product. [41] Free oxygen initially oxidizes dissolved iron in the oceans, creating iron ore. Oxygen concentration in the atmosphere slowly rises, poisoning many bacteria and eventually triggering the Great Oxygenation Event.
2800 MaOldest evidence for microbial life on land in the form of organic matter-rich paleosols, ephemeral ponds and alluvial sequences, some bearing microfossils. [42]

Proterozoic Eon

Detail of the eukaryote endomembrane system and its components Endomembrane system diagram en (edit).svg
Detail of the eukaryote endomembrane system and its components
Dinoflagellate Ceratium furca Ceratium furca.jpg
Dinoflagellate Ceratium furca
Blepharisma japonicum, a free-living ciliated protozoan Mikrofoto.de-Blepharisma japonicum 15.jpg
Blepharisma japonicum , a free-living ciliated protozoan
Dickinsonia costata, an iconic Ediacaran organism, displays the characteristic quilted appearance of Ediacaran enigmata. DickinsoniaCostata.jpg
Dickinsonia costata , an iconic Ediacaran organism, displays the characteristic quilted appearance of Ediacaran enigmata.

2500 Ma 539 Ma. Contains the Palaeoproterozoic, Mesoproterozoic and Neoproterozoic eras.

2500 Ma Great Oxidation Event led by cyanobacteria's oxygenic photosynthesis. [41] Commencement of plate tectonics with old marine crust dense enough to subduct. [28]
By 1850 Ma Eukaryotic cells, containing membrane-bound organelles with diverse functions, probably derived from prokaryotes engulfing each other via phagocytosis. (See Symbiogenesis and Endosymbiont). Bacterial viruses (bacteriophages) emerge before or soon after the divergence of the prokaryotic and eukaryotic lineages. [43] Red beds show an oxidising atmosphere, favouring the spread of eukaryotic life. [44] [45] [46]
1300 MaEarliest land fungi. [47]
By 1200 Ma Meiosis and sexual reproduction in single-celled eukaryotes, possibly even in the common ancestor of all eukaryotes [48] or in the RNA world. [49] Sexual reproduction may have increased the rate of evolution. [50]
By 1000 MaFirst non-marine eukaryotes move onto land. They were photosynthetic and multicellular, indicating that plants evolved much earlier than originally thought. [51]
750 MaBeginning of animal evolution. [52] [53]
720630 MaPossible global glaciation [54] [55] which increased the atmospheric oxygen and decreased carbon dioxide, and was either caused by land plant evolution [56] or resulted in it. [57] Opinion is divided on whether it increased or decreased biodiversity or the rate of evolution. [58] [59] [60]
600 MaAccumulation of atmospheric oxygen allows the formation of an ozone layer. [61] Previous land-based life would probably have required other chemicals to attenuate ultraviolet radiation. [42]
580542 Ma Ediacaran biota, the first large, complex aquatic multicellular organisms. [62]
580500 Ma Cambrian explosion: most modern animal phyla appear. [63] [64]
550540 Ma Ctenophora (comb jellies), [65] Porifera (sponges), [66] Anthozoa (corals and sea anemones), [67] Ikaria wariootia (an early Bilaterian). [68]

Phanerozoic Eon

539 Ma present

The Phanerozoic Eon (Greek: period of well-displayed life) marks the appearance in the fossil record of abundant, shell-forming and/or trace-making organisms. It is subdivided into three eras, the Paleozoic, Mesozoic and Cenozoic, with major mass extinctions at division points.

Palaeozoic Era

538.8 Ma 251.9 Ma and contains the Cambrian, Ordovician, Silurian, Devonian, Carboniferous and Permian periods.

With only a handful of species surviving today, the Nautiloids flourished during the early Paleozoic era, from the Late Cambrian, where they constituted the main predatory animals. Nautilus profile.jpg
With only a handful of species surviving today, the Nautiloids flourished during the early Paleozoic era, from the Late Cambrian, where they constituted the main predatory animals.
Haikouichthys, a jawless fish, is popularized as one of the earliest fishes and probably a basal chordate or a basal craniate. Haikouichthys 3d.png
Haikouichthys , a jawless fish, is popularized as one of the earliest fishes and probably a basal chordate or a basal craniate.
Ferns first appear in the fossil record about 360 million years ago in the late Devonian period. Sa-fern.jpg
Ferns first appear in the fossil record about 360 million years ago in the late Devonian period.
535 Ma Major diversification of living things in the oceans: arthropods (e.g. trilobites, crustaceans), chordates, echinoderms, molluscs, brachiopods, foraminifers and radiolarians, etc.
530 MaThe first known footprints on land date to 530 Ma. [72]
520 MaEarliest graptolites. [73]
511 MaEarliest crustaceans. [74]
505 Ma Fossilization of the Burgess Shale
500 Ma Jellyfish have existed since at least this time.
485 MaFirst vertebrates with true bones (jawless fishes).
450 MaFirst complete conodonts and echinoids appear.
440 MaFirst agnathan fishes: Heterostraci, Galeaspida, and Pituriaspida.
420 MaEarliest ray-finned fishes, trigonotarbid arachnids, and land scorpions. [75]
410 MaFirst signs of teeth in fish. Earliest Nautilida, lycophytes, and trimerophytes.
488400 MaFirst cephalopods (nautiloids) [76] and chitons. [77]
395 MaFirst lichens, stoneworts. Earliest harvestmen, mites, hexapods (springtails) and ammonoids. The earliest known tracks on land named the Zachelmie trackways which are possibly related to icthyostegalians. [78]
375 Ma Tiktaalik, a lobe-finned fish with some anatomical features similar to early tetrapods. It has been suggested to be a transitional species between fish and tetrapods. [79]
365 Ma Acanthostega is one of the earliest vertebrates capable of walking. [80]
363 MaBy the start of the Carboniferous Period, the Earth begins to resemble its present state. Insects roamed the land and would soon take to the skies; sharks swam the oceans as top predators, [81] and vegetation covered the land, with seed-bearing plants and forests soon to flourish.

Four-limbed tetrapods gradually gain adaptations which will help them occupy a terrestrial life-habit.

360 MaFirst crabs and ferns. Land flora dominated by seed ferns. The Xinhang forest grows around this time. [82]
350 MaFirst large sharks, ratfishes, and hagfish; first crown tetrapods (with five digits and no fins and scales).
350 MaDiversification of amphibians. [83]
325-335 MaFirst Reptiliomorpha. [84]
330-320 MaFirst amniote vertebrates ( Paleothyris ). [85]
320 Ma Synapsids (precursors to mammals) separate from sauropsids (reptiles) in late Carboniferous. [86]
305 MaThe Carboniferous rainforest collapse occurs, causing a minor extinction event, as well as paving the way for amniotes to become dominant over amphibians and seed plants over ferns and lycophytes.

First diapsid reptiles (e.g. Petrolacosaurus ).

280 MaEarliest beetles, seed plants and conifers diversify while lepidodendrids and sphenopsids decrease. Terrestrial temnospondyl amphibians and pelycosaurs (e.g. Dimetrodon ) diversify in species.
275 Ma Therapsid synapsids separate from pelycosaur synapsids.
265 Ma Gorgonopsians appear in the fossil record. [87]
251.9251.4 MaThe Permian–Triassic extinction event eliminates over 90-95% of marine species. Terrestrial organisms were not as seriously affected as the marine biota. This "clearing of the slate" may have led to an ensuing diversification, but life on land took 30 million years to completely recover. [88]

Mesozoic Era

Utatsusaurus is the earliest-known ichthyopterygian. Utatsusaurus BW.jpg
Utatsusaurus is the earliest-known ichthyopterygian.
Plateosaurus engelhardti Plateosaurus panorama.jpg
Plateosaurus engelhardti
Cycas circinalis Cycas circinalis.jpg
Cycas circinalis
Synapsids were the largest terrestrial vertebrates in the Permian period, 299 to 251 million years ago. Dimetrodon grandis 3D Model Reconstruction.png
Synapsids were the largest terrestrial vertebrates in the Permian period, 299 to 251 million years ago.
For about 150 million years, dinosaurs were the dominant land animals on Earth. Tyrannosaurus Rex Jane.jpg
For about 150 million years, dinosaurs were the dominant land animals on Earth.

From 251.9 Ma to 66 Ma and containing the Triassic, Jurassic and Cretaceous periods.

250 Ma Mesozoic marine revolution begins: increasingly well adapted and diverse predators stress sessile marine groups; the "balance of power" in the oceans shifts dramatically as some groups of prey adapt more rapidly and effectively than others.
250 Ma Triadobatrachus massinoti is the earliest known frog.
248 Ma Sturgeon and paddlefish (Acipenseridae) first appear.
245 MaEarliest ichthyosaurs
240 MaIncrease in diversity of cynodonts and rhynchosaurs
225 MaEarliest dinosaurs (prosauropods), first cardiid bivalves, diversity in cycads, bennettitaleans, and conifers. First teleost fishes. First mammals ( Adelobasileus ).
220 MaSeed-producing Gymnosperm forests dominate the land; herbivores grow to huge sizes to accommodate the large guts necessary to digest the nutrient-poor plants.[ citation needed ] First flies and turtles ( Odontochelys ). First coelophysoid dinosaurs. First mammals from small-sized cynodonts, which transitioned towards a nocturnal, insectivorous, and endothermic lifestyle.
205 Ma Massive Triassic/Jurassic extinction. It wipes out all pseudosuchians except crocodylomorphs, who transitioned to an aquatic habitat, while dinosaurs took over the land and pterosaurs filled the air.
200 MaFirst accepted evidence for viruses infecting eukaryotic cells (the group Geminiviridae). [89] However, viruses are still poorly understood and may have arisen before "life" itself, or may be a more recent phenomenon.

Major extinctions in terrestrial vertebrates and large amphibians. Earliest examples of armoured dinosaurs.

195 MaFirst pterosaurs with specialized feeding ( Dorygnathus ). First sauropod dinosaurs. Diversification in small, ornithischian dinosaurs: heterodontosaurids, fabrosaurids, and scelidosaurids.
190 Ma Pliosauroids appear in the fossil record. First lepidopteran insects ( Archaeolepis ), hermit crabs, modern starfish, irregular echinoids, corbulid bivalves, and tubulipore bryozoans. Extensive development of sponge reefs.
176 MaFirst Stegosaurian dinosaurs.
170 MaEarliest salamanders, newts, cryptoclidids, elasmosaurid plesiosaurs, and cladotherian mammals. Sauropod dinosaurs diversify.
165 MaFirst rays and glycymeridid bivalves. First vampire squids. [90]
163 Ma Pterodactyloid pterosaurs first appear. [91]
161 Ma Ceratopsian dinosaurs appear in the fossil record ( Yinlong ) and the oldest known eutherian mammal: Juramaia .
160 Ma Multituberculate mammals (genus Rugosodon ) appear in eastern China.
155 MaFirst blood-sucking insects (ceratopogonids), rudist bivalves, and cheilostome bryozoans. Archaeopteryx , a possible ancestor to the birds, appears in the fossil record, along with triconodontid and symmetrodont mammals. Diversity in stegosaurian and theropod dinosaurs.
131 MaFirst pine trees.
140 Ma Orb-weaver spiders appear.
135 MaRise of the angiosperms. Some of these flowering plants bear structures that attract insects and other animals to spread pollen; other angiosperms are pollinated by wind or water. This innovation causes a major burst of animal coevolution. First freshwater pelomedusid turtles. Earliest krill.
120 MaOldest fossils of heterokonts, including both marine diatoms and silicoflagellates.
115 MaFirst monotreme mammals.
114 MaEarliest bees. [92]
112 Ma Xiphactinus , a large predatory fish, appears in the fossil record.
110 MaFirst hesperornithes, toothed diving birds. Earliest limopsid, verticordiid, and thyasirid bivalves.
100 MaFirst ants. [93]
10095 Ma Spinosaurus , the largest theropod dinosaur, appears in the fossil record. [94]
95 MaFirst crocodilians evolve. [95]
90 MaExtinction of ichthyosaurs. Earliest snakes and nuculanid bivalves. Large diversification in angiosperms: magnoliids, rosids, hamamelidids, monocots, and ginger. Earliest examples of ticks. Probable origins of placental mammals (earliest undisputed fossil evidence is 66 Ma).
8676 MaDiversification of therian mammals. [96] [97]
70 MaMultituberculate mammals increase in diversity. First yoldiid bivalves. First possible ungulates (Protungulatum).
6866 Ma Tyrannosaurus , the largest terrestrial predator of western North America, appears in the fossil record. First species of Triceratops. [98]

Cenozoic Era

66 Ma present

Mount of oxyaenid Patriofelis from the American Museum of Natural History Patriofelis-mount.jpg
Mount of oxyaenid Patriofelis from the American Museum of Natural History
The bat Icaronycteris appeared 52.2 million years ago Icaronycteris index.jpg
The bat Icaronycteris appeared 52.2 million years ago
Grass flowers Grassflowers.jpg
Grass flowers
Reconstructed skeletons of flightless terror bird and ground sloth at the Museu Nacional, Rio de Janeiro 1064376 - Megafauna - Museu Nacional de Historia Natural UFRJ - 22 Outubro 2010 - Rio de Janeiro - Brazil.jpg
Reconstructed skeletons of flightless terror bird and ground sloth at the Museu Nacional, Rio de Janeiro
Diprotodon went extinct about 40,000 years ago as part of the Quaternary extinction event, along with every other Australian creature over 100 kg (220 lb). Diprotodon optatum (2).jpg
Diprotodon went extinct about 40,000 years ago as part of the Quaternary extinction event, along with every other Australian creature over 100 kg (220 lb).
50,000 years ago several different human species coexisted on Earth including modern humans and Homo floresiensis (pictured). Homo floresiensis v 2-0.jpg
50,000 years ago several different human species coexisted on Earth including modern humans and Homo floresiensis (pictured).
American lions exceeded extant lions in size and ranged over much of North America until 11,000 BP. PantheraLeoAtrox1 (retouched).jpg
American lions exceeded extant lions in size and ranged over much of North America until 11,000 BP.
66 MaThe Cretaceous–Paleogene extinction event eradicates about half of all animal species, including mosasaurs, pterosaurs, plesiosaurs, ammonites, belemnites, rudist and inoceramid bivalves, most planktic foraminifers, and all of the dinosaurs excluding the birds. [99]
66 Ma-Rapid dominance of conifers and ginkgos in high latitudes, along with mammals becoming the dominant species. First psammobiid bivalves. Earliest rodents. Rapid diversification in ants.
63 MaEvolution of the creodonts, an important group of meat-eating (carnivorous) mammals.
62 MaEvolution of the first penguins.
60 MaDiversification of large, flightless birds. Earliest true primates,[ who? ] along with the first semelid bivalves, edentate, carnivoran and lipotyphlan mammals, and owls. The ancestors of the carnivorous mammals (miacids) were alive.[ citation needed ]
59 MaEarliest sailfish appear.
56 Ma Gastornis , a large flightless bird, appears in the fossil record.
55 MaModern bird groups diversify (first song birds, parrots, loons, swifts, woodpeckers), first whale ( Himalayacetus ), earliest lagomorphs, armadillos, appearance of sirenian, proboscidean mammals in the fossil record. Flowering plants continue to diversify. The ancestor (according to theory) of the species in the genus Carcharodon , the early mako shark Isurus hastalis, is alive. Ungulates split into artiodactyla and perissodactyla, with some members of the former returning to the sea.
52 MaFirst bats appear ( Onychonycteris ).
50 MaPeak diversity of dinoflagellates and nannofossils, increase in diversity of anomalodesmatan and heteroconch bivalves, brontotheres, tapirs, rhinoceroses, and camels appear in the fossil record, diversification of primates.
40 MaModern-type butterflies and moths appear. Extinction of Gastornis . Basilosaurus , one of the first of the giant whales, appeared in the fossil record.
38 MaEarliest bears.
37 MaFirst nimravid ("false saber-toothed cats") carnivores — these species are unrelated to modern-type felines. First alligators and ruminants.
35 Ma Grasses diversify from among the monocot angiosperms; grasslands begin to expand. Slight increase in diversity of cold-tolerant ostracods and foraminifers, along with major extinctions of gastropods, reptiles, amphibians, and multituberculate mammals. Many modern mammal groups begin to appear: first glyptodonts, ground sloths, canids, peccaries, and the first eagles and hawks. Diversity in toothed and baleen whales.
33 MaEvolution of the thylacinid marsupials ( Badjcinus ).
30 MaFirst balanids and eucalypts, extinction of embrithopod and brontothere mammals, earliest pigs and cats.
28 Ma Paraceratherium appears in the fossil record, the largest terrestrial mammal that ever lived. First pelicans.
25 Ma Pelagornis sandersi appears in the fossil record, the largest flying bird that ever lived.
25 MaFirst deer.
24 MaFirst pinnipeds.
23 MaEarliest ostriches, trees representative of most major groups of oaks have appeared by now. [100]
20 MaFirst giraffes, hyenas, and giant anteaters, increase in bird diversity.
17 MaFirst birds of the genus Corvus (crows).
15 MaGenus Mammut appears in the fossil record, first bovids and kangaroos, diversity in Australian megafauna.
10 MaGrasslands and savannas are established, diversity in insects, especially ants and termites, horses increase in body size and develop high-crowned teeth, major diversification in grassland mammals and snakes.
9.5 Ma [ dubious ] Great American Interchange, where various land and freshwater faunas migrated between North and South America. Armadillos, opossums, hummingbirds Phorusrhacids, Ground Sloths, Glyptodonts, and Meridiungulates traveled to North America, while horses, tapirs, saber-toothed cats, jaguars, bears, coaties, ferrets, otters, skunks and deer entered South America.
9 MaFirst platypuses.
6.5 MaFirst hominins ( Sahelanthropus ).
6 Ma Australopithecines diversify ( Orrorin , Ardipithecus ).
5 MaFirst tree sloths and hippopotami, diversification of grazing herbivores like zebras and elephants, large carnivorous mammals like lions and the genus Canis , burrowing rodents, kangaroos, birds, and small carnivores, vultures increase in size, decrease in the number of perissodactyl mammals. Extinction of nimravid carnivores. First leopard seals.
4.8 Ma Mammoths appear in the fossil record.
4.5 Ma Marine iguanas diverge from land iguanas.
4 Ma Australopithecus evolves. Stupendemys appears in the fossil record as the largest freshwater turtle, first modern elephants, giraffes, zebras, lions, rhinoceros and gazelles appear in the fossil record
3.6 Ma Blue whales grow to modern size.
3 MaEarliest swordfish.
2.7 Ma Paranthropus evolves.
2.5 MaEarliest species of Smilodon evolve.
2 MaFirst members of genus Homo, Homo Habilis, appear in the fossil record. Diversification of conifers in high latitudes. The eventual ancestor of cattle, aurochs (Bos primigenus), evolves in India.
1.7 MaAustralopithecines go extinct.
1.2 MaEvolution of Homo antecessor . The last members of Paranthropus die out.
1 MaFirst coyotes.
800 Ka Short-faced bears (Arctodus simus) become abundant in North America
600 kaEvolution of Homo heidelbergensis.
400 kaFirst polar bears.
350 kaEvolution of Neanderthals.
300 ka Gigantopithecus , a giant relative of the orangutan from Asia dies out.
250 kaAnatomically modern humans appear in Africa. [101] [102] [103] Around 50 ka they start colonising the other continents, replacing Neanderthals in Europe and other hominins in Asia.
70 kaGenetic bottleneck in humans (Toba catastrophe theory).
40 kaLast giant monitor lizards (Varanus priscus) die out.
35-25 kaExtinction of Neanderthals. Domestication of dogs.
15 kaLast woolly rhinoceros (Coelodonta antiquitatis) are believed to have gone extinct.
11 kaShort-faced bears vanish from North America, with the last giant ground sloths dying out. All Equidae become extinct in North America. Domestication of various ungulates.
10 ka Holocene epoch starts [104] after the Last Glacial Maximum. Last mainland species of woolly mammoth (Mammuthus primigenus) die out, as does the last Smilodon species.
8 kaThe Giant Lemur dies out.

See also

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The Proterozoic is the third of the four geologic eons of Earth's history, spanning the time interval from 2500 to 538.8 Mya, the longest eon of the Earth's geologic time scale. It is preceded by the Archean and followed by the Phanerozoic, and is the most recent part of the Precambrian "supereon".

<span class="mw-page-title-main">Doushantuo Formation</span>

The Doushantuo Formation is a geological formation in western Hubei, eastern Guizhou, southern Shaanxi, central Jiangxi, and other localities in China. It is known for the fossil Lagerstätten in Zigui in Hubei, Xiuning in Anhui, and Weng'an in Guizhou, as one of the oldest beds to contain minutely preserved microfossils, phosphatic fossils that are so characteristic they have given their name to "Doushantuo type preservation". The formation, whose deposits date back to the Early and Middle Ediacaran, is of particular interest because it covers the poorly understood interval of time between the end of the Cryogenian geological period and the more familiar fauna of the Late Ediacaran Avalon explosion, as well as due to its microfossils' potential utility as biostratigraphical markers. Taken as a whole, the Doushantuo Formation ranges from about 635 Ma at its base to about 551 Ma at its top, with the most fossiliferous layer predating by perhaps five Ma the earliest of the 'classical' Ediacaran faunas from Mistaken Point on the Avalon Peninsula of Newfoundland, and recording conditions up to a good forty to fifty million years before the Cambrian explosion at the beginning of the Phanerozoic.

<span class="mw-page-title-main">Cryogenian</span> Second period of the Neoproterozoic Era, with major glaciation

The Cryogenian is a geologic period that lasted from 720 to 635 million years ago. It forms the second geologic period of the Neoproterozoic Era, preceded by the Tonian Period and followed by the Ediacaran.

<span class="mw-page-title-main">Marine life</span> Organisms that live in salt water

Marine life, sea life, or ocean life is the plants, animals, and other organisms that live in the salt water of seas or oceans, or the brackish water of coastal estuaries. At a fundamental level, marine life affects the nature of the planet. Marine organisms, mostly microorganisms, produce oxygen and sequester carbon. Marine life in part shape and protect shorelines, and some marine organisms even help create new land.

<span class="mw-page-title-main">History of Earth</span> Development of planet Earth from its formation to the present day

The history of Earth concerns the development of planet Earth from its formation to the present day. Nearly all branches of natural science have contributed to understanding of the main events of Earth's past, characterized by constant geological change and biological evolution.

<span class="mw-page-title-main">Evolution of molluscs</span> The origin and diversification of molluscs through geologic time

The evolution of the molluscs is the way in which the Mollusca, one of the largest groups of invertebrate animals, evolved. This phylum includes gastropods, bivalves, scaphopods, cephalopods, and several other groups. The fossil record of mollusks is relatively complete, and they are well represented in most fossil-bearing marine strata. Very early organisms which have dubiously been compared to molluscs include Kimberella and Odontogriphus.

<span class="mw-page-title-main">Ediacaran biota</span> All organisms of the Ediacaran Period (c. 635–538.8 million years ago)

The Ediacaranbiota is a taxonomic period classification that consists of all life forms that were present on Earth during the Ediacaran Period. These were enigmatic tubular and frond-shaped, mostly sessile, organisms. Trace fossils of these organisms have been found worldwide, and represent the earliest known complex multicellular organisms. The term "Ediacara biota" has received criticism from some scientists due to its alleged inconsistency, arbitrary exclusion of certain fossils, and inability to be precisely defined.

The history of life on Earth traces the processes by which living and fossil organisms evolved, from the earliest emergence of life to present day. Earth formed about 4.5 billion years ago and evidence suggests that life emerged prior to 3.7 Ga. Although there is some evidence of life as early as 4.1 to 4.28 Ga, it remains controversial due to the possible non-biological formation of the purported fossils.

<span class="mw-page-title-main">Evolution of fungi</span> Origin and diversification of fungi through geologic time

Fungi diverged from other life around 1.5 billion years ago, with the glomaleans branching from the "higher fungi" (dikaryans) at ~570 million years ago, according to DNA analysis. Fungi probably colonized the land during the Cambrian, over 500 million years ago,, and possibly 635 million years ago during the Ediacaran, but terrestrial fossils only become uncontroversial and common during the Devonian, 400 million years ago.

The end-Ediacaran extinction is a mass extinction believed to have occurred near the end of the Ediacaran period, the final period of the Proterozoic eon. Evidence suggesting that such a mass extinction occurred includes a massive reduction in diversity of acritarchs, the sudden disappearance of the Ediacara biota and calcifying organisms, and the time gap before Cambrian organisms "replaced" them. Some lines of evidence suggests that there may have been two distinct pulses of the extinction event, one occurring 550 million years ago and the other 539 million years ago.

The Cambrian explosion, Cambrian radiation,Cambrian diversification, or the Biological Big Bang refers to an interval of time approximately 538.8 million years ago in the Cambrian Period of early Paleozoic when there was a sudden radiation of complex life and practically all major animal phyla started appearing in the fossil record. It lasted for about 13 – 25 million years and resulted in the divergence of most modern metazoan phyla. The event was accompanied by major diversification in other groups of organisms as well.

<span class="mw-page-title-main">Evolution of fish</span> Origin and diversification of fish through geologic time

The evolution of fish began about 530 million years ago during the Cambrian explosion. It was during this time that the early chordates developed the skull and the vertebral column, leading to the first craniates and vertebrates. The first fish lineages belong to the Agnatha, or jawless fish. Early examples include Haikouichthys. During the late Cambrian, eel-like jawless fish called the conodonts, and small mostly armoured fish known as ostracoderms, first appeared. Most jawless fish are now extinct; but the extant lampreys may approximate ancient pre-jawed fish. Lampreys belong to the Cyclostomata, which includes the extant hagfish, and this group may have split early on from other agnathans.


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