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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 ...
Utahraptor (meaning " Utah 's predator") is a genus of large dromaeosaurid (a group of feathered carnivorous theropods) dinosaur that lived during the Early Cretaceous period from around 135 to 130 million years ago in what is now the United States. The genus was described in 1993 by American paleontologist James Kirkland and colleagues with ...
Palaeomagnetism suggests Member 3 may date to 1.78–1.6 million years ago, Member 2 to before 1.78 million years ago, and Member 1 to 2.11–1.95 million years ago. [97] The animal remains of Kromdraai A suggest deposition occurred anywhere between 1.89 and 1.63 million years ago, and the presence of Oldowan or Achulean tools indicates early ...
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 ...
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 trackway Protichnites from the Cambrian, Blackberry Hill, central Wisconsin. A trace fossil, also known as an ichnofossil ( / ˈɪknoʊfɒsɪl /; from Greek: ἴχνος ikhnos "trace, track"), is a fossil record of biological activity by lifeforms but not the preserved remains of the organism itself. [1] Trace fossils contrast with body ...
Dart, 1949. Australopithecus africanus is an extinct species of australopithecine which lived between about 3.3 and 2.1 million years ago in the Late Pliocene to Early Pleistocene of South Africa. [1] The species has been recovered from Taung, Sterkfontein, Makapansgat, and Gladysvale.