Late Pleistocene
Late/Upper Pleistocene | ||||||||||||||||||||||||||||||
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Chronology | ||||||||||||||||||||||||||||||
The Late Pleistocene is an unofficial geologic timescale in chronostratigraphy, also known as the upper Pleistocene from a stratigraphic perspective. It is intended to be the fourth division of the Pleistocene Epoch within the ongoing Quaternary Period. It is currently defined as the time between c. 129,000 and c. 11,700 years ago. The late Pleistocene equates to the proposed Tarantian Age of the geologic time scale, preceded by the officially ratified Chibanian (commonly known as Middle Pleistocene).[1] The beginning of the Late Pleistocene is the transition between the end of the Penultimate Glacial Period and the beginning of the Last Interglacial around 130,000 years ago (corresponding with the beginning of Marine Isotope Stage 5).[5] The Late Pleistocene ends with the termination of the Younger Dryas, some 11,700 years ago when the Holocene Epoch began.[2]
The term Upper Pleistocene is currently in use as a provisional or "quasi-formal" designation by the International Union of Geological Sciences (IUGS). Although the three oldest ages of the Pleistocene (the Gelasian, the Calabrian and the Chibanian) have been officially defined, the late Pleistocene has yet to be formally defined.[6] Following the brief Last Interglacial warm period (~130-115,000 years ago), where temperatures were comparable to or warmer than the Holocene, the Late Pleistocene was dominated by the cool Last Glacial Period, with temperatures graduate lowering over the course of the period, reaching their lowest during the Last Glacial Maximum around 26-20,000 years ago. Most of the world's large ( archaic human species.
Last Ice Age
The proposed beginning of the late Pleistocene is the end of the Devensian (Great Britain) or Weichselian glaciation (northern Europe); these are broadly equated with the Wisconsin glaciation (North America), though technically that began much later.[7]
The The Last Ice Age was followed by the interstadials from about 16 ka until the end of the Pleistocene. These were the Oldest Dryas (stadial), the Bølling oscillation (interstadial), the Older Dryas (stadial), the Allerød oscillation (interstadial) and finally the Younger Dryas.[10]
The end of the Younger Dryas marks the boundary between the Pleistocene and Holocene Epochs. Man in all parts of the world was still culturally and technologically in the Palaeolithic (Old Stone) Age. Tools and weapons were basic stone or wooden implements. Nomadic tribes followed moving herds. Non-nomadics acquired their food by gathering and hunting.[11]
AfricaIn Nile Valley as the Sahara was transformed from grassland to desert.[12] The Nazlet Khater skeleton was found in 1980 and has been radiocarbon dated to between 30,360 and 35,100 years ago.[13][14]
EurasiaNeanderthal hominins (Homo neanderthalensis) inhabited Eurasia until becoming extinct between 40 and 30 ka.[11][15] Towards the end of the Pleistocene and possibly into the early Holocene, several large mammalian species including the woolly rhinoceros, mammoth, mastodon and Irish elk became extinct.[15] Cave paintings have been found at Lascaux in the Dordogne which may be more than 17,000 years old. These are mainly of buffalo, deer and other animals hunted by man. Later paintings occur in caves throughout the world with further examples at Altamira (Spain) and in India, Australia and the Sahara.[16][15] better source needed ]
The only domesticated animal in the Pleistocene was the breeds. It is believed that the grey wolf became associated with hunter-gatherer tribes around 15 ka.[19] The earliest remains of a true domestic dog have been dated to 14,200 years ago.[20] Domestication first happened in Eurasia but could have been anywhere from Western Europe to East Asia.[21] Domestication of other animals such as cattle, goats, pigs and sheep did not begin until the Holocene when settled farming communities became established in the Near East.[19] The cat was probably not domesticated before c. 7500 BC at the earliest, again in the Near East.[22]
A butchered brown bear patella found in Alice and Gwendoline Cave in County Clare and dated to 10,860 to 10,641 BC indicates the first known human activity in Ireland.[23] Far EastThe very first human habitation in the Japanese archipelago has been traced to prehistoric times between 40,000 BC and 30,000 BC. The earliest fossils are radiocarbon dated to c. 35,000 BC. Japan was once linked to the Asian mainland by land bridges via Hokkaido and Sakhalin Island to the north, but was unconnected at this time when the main islands of Hokkaido, Honshu, Kyushu and Shikoku were all separate entities.[24] North AmericaFrom about 28 ka, there were migrations across the Bering land bridge from Siberia to Alaska. The people became the Native Americans. It is believed that the original tribes subsequently moved down to Central and South America under pressure from later migrations.[9][15] In the North American land mammal age scale, the Rancholabrean spans the time from c. 240,000 years ago to c. 11,000 years ago. It is named after the Rancho La Brea fossil site in California, characterised by extinct forms of bison in association with other Pleistocene species such as the mammoth.[25][26][27]
South America
A large number of megafauna in South and North America went extinct during the Pleistocene. In North America, about 70% of mammals weighing about 44 kg went extinct during the time period of 13 -12 k cal BP. During this period there was a major cooling event called the Younger dryas and the Clovis culture of capturing game became more prominent.[29] Diverse factors such as climate change may have triggered this extinctions but its still in debate what the major factors were.[30] The South American land mammal age Lujanian corresponds with the late Pleistocene. OceaniaThere is evidence of human habitation in mainland Australia, Indonesia, New Guinea and Tasmania from c. 45,000 BC. The finds include rock engravings, stone tools and evidence of cave habitation.[31] References
Bibliography
Further reading
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