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Late Devonian: 375 million years ago, 75% of species lost, including most trilobites. End Permian, The Great Dying: 251 million years ago, 96% of species lost, including tabulate corals, and most trees and synapsids. End Triassic: 200 million years ago, 80% of species lost, including all conodonts. End Cretaceous: 66 million years ago, 76% of ...
The timeline of human evolution outlines the major events in the evolutionary lineage of the modern human species, Homo sapiens, throughout the history of life, beginning some 4 billion years ago down to recent evolution within H. sapiens during and since the Last Glacial Period. It includes brief explanations of the various taxonomic ranks in ...
The time of appearance of the earliest eutherians has been a matter of controversy. On one hand, recently discovered fossils of Juramaia have been dated to 160 million years ago and classified as eutherian. [73] Fossils of Eomaia from 125 million years ago in the Early Cretaceous have also been classified as eutherian. [74]
The history of life on Earth traces the processes by which living and extinct organisms evolved, from the earliest emergence of life to the present day. Earth formed about 4.5 billion years ago (abbreviated as Ga, for gigaannum) and evidence suggests that life emerged prior to 3.7 Ga. [1] [2] [3] The similarities among all known present-day species indicate that they have diverged through the ...
Millions of years before the earliest birds appeared, mystery animals walked around on birdlike feet, study finds. Mindy Weisberger, CNN. ... (201.3 million to 145 million years ago); the ...
The last common ancestor of all extant eukaryotes is thought to have lived around 1.8 billion years ago. Around 800 million years ago, there was a notable increase in the complexity and number of eukaryotes species in the fossil record. [133] Before the spike in diversity, eukaryotes are thought to have lived in highly sulfuric environments.
Swisher and others dated the formation of the Chicxulub Crater to 65 million years ago. [39] More precisely, they dated igneous rock from the Chicxulub crater to 64.98 million years ago. [100] Sheehan and Fastovsky found terrestrial vertebrates to be the primary victims of the end Cretaceous extinction event, with 88% of their biodiversity lost.
The hominoids are descendants of a common ancestor. Human evolution is the evolutionary process within the history of primates that led to the emergence of Homo sapiens as a distinct species of the hominid family that includes all the great apes. [1] This process involved the gradual development of traits such as human bipedalism, dexterity ...