![]() ![]() However, there remains no consensus among scholars on the timing of human migration into the Americas. Modern humans then made their way across the Bering land bridge and into North America between 20,000 and 11,000 years ago, after the Wisconsin glaciation had retreated but before the Bering land bridge became inundated by the sea. ![]() Remains of mammoth that had been hunted by humans 45,000 YBP have been found at Yenisei Bay in the central Siberian Arctic. Another group left Central Asia and reached the lower Yana River, Siberia, well above the Arctic circle, 27,000 years ago. From there they reached Europe, with human remains dated to 43,000-45,000 years BP discovered in Italy, Britain, and in the European Russian Arctic dated to 40,000 years ago. Some migrated out of Africa 60,000 years ago, with one group reaching Central Asia 50,000 years ago. ![]() The ancestors of modern humans first appeared in East Africa 195,000 years ago. Multiple events appear to also involve the rapid replacement of one species by one within the same genus, or one population by another within the same species, across a broad area. There is no evidence of megafaunal extinctions at the height of the LGM, indicating that increasing cold and glaciation were not factors. The Late Pleistocene was characterized by a series of severe and rapid climate oscillations with regional temperature changes of up to 16 ☌, which has been correlated with megafaunal extinctions. Among the top predators, the sabre-toothed cat ( Homotherium) died out 28,000 years BP, the cave lion 11,900 years BP, and the leopard in Europe died out 27,000 years BP. As some species became extinct, so too did their predators. A pocket of mammoths survived on Wrangel Island until 4,500 years BP. The giant deer died out after 11,500 BP with the last pocket having survived until about 7,700 years BP in western Siberia. The woolly rhinoceros and mammoths died out between 16,000 and 11,500 years BP. The cave bear ( Ursus spelaeus), interglacial rhinoceros ( Stephanorhinus), heavy-bodied Asian antelope ( Spirocerus), and the Eurasian hippopotamuses died out between 50,000 and 16,000 years BP. Across Eurasia, the straight-tusked elephant became extinct between 100,000 and 50,000 years BP. Scientists frequently define megafauna as the set of animals with an adult body weight of over 45 kg (or 99 lbs). These animals have been termed the Pleistocene megafauna. The fossil evidence from many continents points to the extinction mainly of large animals at or near the end of the last glaciation. Forest and woodland was almost non-existent, except for isolated pockets in the mountain ranges of southern Europe. During the last glacial maximum, the continent of Europe was much colder and drier than it is today, with polar desert in the north and the remainder steppe or tundra. ![]() When the sea levels began to rise this bridge was inundated around 11,000 years BP. This land bridge existed because more of the planet's water was locked up in glaciation than now and therefore the sea levels were lower. Ī vast mammoth steppe stretched from the Iberian peninsula across Eurasia and over the Bering land bridge into Alaska and the Yukon where it was stopped by the Wisconsin glaciation. Deglaciation commenced in the Northern Hemisphere approximately 19,000 years BP, and in Antarctica approximately 14,500 years BP which is consistent with evidence that this was the primary source for an abrupt rise in the sea level 14,500 years ago. The Ice Age reached its peak during the last glacial maximum, when ice sheets commenced advancing from 33,000 years BP and reached their maximum positions 26,500 years BP. The last glacial period, commonly referred to as the 'Ice Age', spanned 125,000 to 14,500 years ago and was the most recent glacial period within the current ice age which occurred during the final years of the Pleistocene epoch. Paleoecology Ukok Plateau, one of the last remnants of the mammoth steppe The precise definition of megafauna is contentious, though a common definition are any animals with an adult body weight of over 45 kilograms (99 lb). The role of humans in causing Pleistocene megafaunal extinctions is controversial. Most Pleistocene megafauna outside of Africa became extinct during the Quaternary extinction event during the Late Pleistocene, resulting in substantial changes to ecosystems globally. Pleistocene megafauna is the set of large animals ( megafauna) that lived on Earth during the Pleistocene epoch. Recreation of a scene in late Pleistocene northern Spain, by Mauricio Antón It has been suggested that this article be merged into Quaternary extinction event. ![]()
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