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The timeline of the evolutionary history of liferepresents the current scientific theoryoutlining the major events during the development of lifeon planet Earth. Dates in this article are consensus estimates based on scientific evidence, mainly fossils. In biology, evolutionis any change across successive generations in the heritable ...
Appearance. The Great Ordovician Biodiversification Event (GOBE), was an evolutionary radiation of animal life throughout [ 1 ] the Ordovician period, 40 million years after the Cambrian explosion, [ 2 ] whereby the distinctive Cambrian fauna fizzled out to be replaced with a Paleozoic fauna rich in suspension feeder and pelagic animals.
The Paleozoic (/ ˌ p æ l i. ə ˈ z oʊ. ɪ k,-i. oʊ-, ˌ p eɪ-/ PAL-ee-ə-ZOH-ik, -ee-oh-, PAY-; [1] or Palaeozoic) Era is the first of three geological eras of the Phanerozoic Eon. . Beginning 538.8 million years ago (Ma), it succeeds the Neoproterozoic (the last era of the Proterozoic Eon) and ends 251.9 Ma at the start of the Mesozoic Er
Figure 1:In mammals, the quadrate and articular bones are small and part of the middle ear; the lower jaw consists only of dentary bone.. While living mammal species can be identified by the presence of milk-producing mammary glands in the females, other features are required when classifying fossils, because mammary glands and other soft-tissue features are not visible in fossils.
1991 [1] The Paleoproterozoic Era[4] (also spelled Palaeoproterozoic) is the first of the three sub-divisions (eras) of the Proterozoic eon, and also the longest era of the Earth's geological history, spanning from 2,500 to 1,600 million years ago (2.5–1.6 Ga).
The Ediacaran (/ ˌiːdiˈækərən /; formerly Vendian) biota is a taxonomic period classification that consists of all life forms that were present on Earth during the Ediacaran Period (c.635–538.8 Mya). These were enigmatic tubular and frond-shaped, mostly sessile, organisms. [ 1 ][ 2 ] Trace fossils of these organisms have been found ...
They first appeared in the fossil record around 66 million years ago, soon after the Cretaceous–Paleogene extinction event that eliminated about three-quarters of plant and animal species on Earth, including most dinosaurs. [25] [26] One of the last Plesiadapiformes is Carpolestes simpsoni, having grasping digits but not forward-facing eyes ...
Insects are thought to have evolved from a group of crustaceans. [ 2 ] The first insects were landbound, but about 400 million years ago in the Devonian period one lineage of insects evolved flight, the first animals to do so. [ 1 ] The oldest insect fossil has been proposed to be Rhyniognatha hirsti, estimated to be 400 million years old, but ...