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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.
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 ...
However, in a narrow and more colloquial sense, the term "dinosaur" often refers specifically to non-avian dinosaurs, all of which died out in the Cretaceous–Paleogene extinction about 66 million years ago, while the genus Homo emerged only about 3 million years ago, leaving a period of tens of millions of years between the last dinosaurs and ...
Homo erectus (/ ˌ h oʊ m oʊ ə ˈ r ɛ k t ə s / lit. ' upright man ') is an extinct species of archaic human from the Pleistocene, spanning nearly 2 million years.It is the first human species to evolve a humanlike body plan and gait, to leave Africa and colonize Asia and Europe, and to wield fire.
The relatively large size of most dinosaurs and the low diversity of small-bodied dinosaur species at the end of the Cretaceous may have contributed to their extinction; [277] the extinction of the bird lineages that did not survive may also have been caused by a dependence on forest habitats or a lack of adaptations to eating seeds for survival.
Dinosaurs evolved from more primitive reptiles in the aftermath of Earth's biggest mass-extinction event caused by extreme volcanism at the end of the Permian Period about 252 million years ago ...
These nine wooden spears and spear fragments—in addition to a lance, and a double-pointed stick—date to 300,000 years ago and were preserved along a lakeside. The spears vary from 2.9–4.7 cm (1.1–1.9 in) in diameter, and may have been 210–240 cm (7–8 ft) long, overall similar to present day competitive javelins.
Neanderthals became extinct around 40,000 years ago. Hypotheses on the causes of the extinction include violence, transmission of diseases from modern humans which Neanderthals had no immunity to, competitive replacement, extinction by interbreeding with early modern human populations, natural catastrophes, climate change and inbreeding ...