The term Upper Pleistocene is currently in use as a provisional or "quasi-formal" designation by theInternational Union of Geological Sciences (IUGS). Although the three oldest ages of the Pleistocene (theGelasian, theCalabrian and theChibanian) have been officially defined, the late Pleistocene has yet to be formally defined.[7]
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 coolLast Glacial Period, with temperatures gradually lowering throughout the period, reaching their lowest during theLast Glacial Maximum around 26–20,000 years ago.
The Late Pleistocene from around 50,000 years ago onwards was marked bythe extinction of most large terrestrial animals outside of Africa, an extinction event otherwise unprecedented in the geological record due to its extreme size bias. Most authors suggest that climate change, the expansion of modern humans, or the combination of both were the likely causes of the extinctions.
TheLast Glacial Maximum was reached during the later millennia of the Würm/Weichselian, estimated between 26 ka and 19 ka when deglaciation began in the Northern Hemisphere. The Würm/Weichselian endured until 16 ka with Northern Europe, including most ofGreat Britain, covered by an ice sheet. The glaciers reached theGreat Lakes in North America.[2] Sea levels fell and twoland bridges were temporarily in existence that had significance forhuman migration:Doggerland, which connected Great Britain to mainland Europe; and theBering land bridge which joinedAlaska toSiberia.[9][10]
The end of the Younger Dryas marks the boundary between the Pleistocene and Holocene Epochs. Hominids in all parts of the world were still culturally and technologically in thePalaeolithic (Old Stone) Age. Tools and weapons were basic stone or wooden implements.Nomadic tribes followed moving herds. Non-nomadics acquired their food bygathering and hunting.[12]
Its present physical geography and climate have changed over time caused by the movement oftectonic plates and volcanoes butglacial cycles and sea level variation have a more significant effect on thevertebrate communities during the Late Pleistocene.[13]
The Late Pleistocene was the time when most animals evolved to resemble modern-dayanimals and they managed to live through the Late mid-Pleistocene since there were no extinction events ofmegafauna until the end of the Late Pleistocene.[13]
Some species which went extinct at the end of the Late Pleistocene in Southern Africa are thegiant warthog, long-horn buffalo,Southern springbok, etc.[14] These species were common because their distribution changed in response to climatic influences on vegetation.Carnivores were more widespread due to their varying habitat requirements.
image of Nazlet Khater skeleton found in Upper Egypt showing early human culture dating back to approximately 30–40 Ka
InEgypt, the Late (or Upper)Palaeolithic began sometime after 30,000 BC. People in North Africa had relocated to theNile Valley as theSahara was transformed from grassland to desert.[15] TheNazlet Khater skeleton was found in 1980 and has beenradiocarbon dated to between 30,360 and 35,100 years ago.[16][17]
Most of the knowledge of the Late Pleistocene is obtained from regions likeMorocco,Algeria,Tunisia, some coastal regions ofMaghreb,Libya andEgypt. The only issue with interpreting the data from this region is due to the lack of chronological information.[13] The resemblance of Late Pleistocene species in Northern Africa to modern animals is the same as in Southern Africa but it's extremely difficult to date when these fauna came into place because of the lack of reliable samples from the mid-Pleistocene.[18] Most of the significant fossil records are from the Maghreb because of itsgeology which helps to create deep caves which is conducive for preservingfossils.
Neanderthal hominins (Homo neanderthalensis) inhabited Eurasia until becoming extinct between 40 and 30 ka, towards the end of the Pleistocene and possibly into the early Holocene[12][19]and were replaced with modern humans (Homo sapiens) who emerged from East Africa about 195,000 years ago.[20] Neanderthals co-existed with theHomo sapiens until they died out.[citation needed]
In Eurasia, extinction happened throughout the Pleistocene but those that happened during the Later Pleistocene were of megafauna and there were no replacements for the extinct species.[citation needed] SomeMolluscan species went extinct but not on the same scale as the mammals living during the time.[21] Some examples of species which extinct without replacements include theStraight-tusked elephant (Palaeoloxodon antiquus),Giant deer (Megaloceros giganteus),cave bear (Ursus spelaeus) andwoolly rhinoceros (Coelodonta antiquitatis).[22] Several large mammalian species including themammoth,mastodon, andIrish elk became extinct.[23]
Upper Paleolithic people also made paintings and engravings on walls.Cave paintings have been found atLascaux in theDordogne which may be more than 17,000 years old. These are mainlybuffalo,deer, and other animals hunted by humans. Later paintings occur in caves throughout the world, includingAltamira, Spain, and in India, Australia, and the Sahara.[19][24]
Magdalenian hunter-gatherers were widespread in western Europe about 20–12.500cal BP years ago until the end of the Pleistocene.[25] An example of this is the antler-working done by the human groups who lived in theSantimamine cave in the Magdalenian.[26] They invented the earliest knownharpoons usingreindeer horn.[27]
Climatic conditions during the Late Pleistocene in Eurasia were predominantly cold withglaciation events happening innorthern Europe, northwestSiberia andthe Alps andinterglacials (temperate phase). The evidence of the changes in climatic conditions was from fragmentary sequences in formerly glaciated areas innorthern Europe.[22]
The only domesticated animal in the Pleistocene was thedog, which evolved from thegrey wolf into its many modernbreeds. It is believed that the grey wolf became associated with hunter-gatherer tribes around 15 Ka.[28] The earliest remains of a true domestic dog have been dated to 14,200 years ago.[29] Domestication first happened in Eurasia but could have been anywhere from Western Europe to East Asia.[30] 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.[28] Thecat was probably not domesticated beforec. 7500 BC at the earliest, again in theNear East.[31]
Japan was once linked to the Asian mainland by land bridges viaHokkaido andSakhalin Island to the north but was unconnected at this time when the main islands of Hokkaido,Honshu,Kyushu andShikoku were all separate entities.[37]
Human migrations happened during this time with people coming in fromEurasia. From about 28 ka, there were migrations across theBering land bridge fromSiberia toAlaska. The people became theNative Americans. It is believed that the original tribes subsequently moved down to Central and South America under pressure from later migrations.[10][19]
Bison occidentalis andBison antiquus, an extinct relative of the smaller present-dayAmerican bison, survived the late Pleistocene period, between about 12 and 11ka ago.Clovis people depended on these bison as their major food source. Earlier kills of camels, horses, and muskoxen found atWally's beach were dated to 13.1–13.3 ka B.P.[41]
Over 50 genera (~ 83%) ofmegafauna in South andNorth America went extinct during the Pleistocene.[42] Most mega mammals (>1000kg) and large mammals (>40kg) went extinct by the end of the Late Pleistocene.[43] During this period there was a major cooling event called theYounger Dryas and theClovis culture of capturing game became more prominent.[44] Diverse factors such as climate change may have triggered this extinction but it's still in debate what the major factors were.[45]
The Late Pleistocene saw a change in the use of coastal resources and advancements in marine technology. The reasons for these changes have not been confirmed; various triggering mechanisms have been theorized such asclimate change, the arrival of new people, or the struggle for resources.[46]
There is evidence of human habitation in mainlandAustralia,Indonesia,New Guinea andTasmania from c. 45,000 BC. The finds include rock engravings, stone tools and evidence of cave habitation.[48]
In Australia, there are sites which show evidence of pollen records from the Late Pleistocene and they are mostly found in moretemperate regions of the continent.[49] Some megafauna decreased in size over time, while others remained the same; however, the fossil record is limited in the exact chronologies of the extinctions.[50]
Extinction ofAustralian megafauna appears to have taken place earlier than in the Americas or the extinction of the Eurasian mammoth steppe fauna, with an estimated peak of extinction of around 42,000 years ago.[51] In general, various reasons have been stated to have caused the extinctions during the Late Pleistocene but the topic is still being debated.[52]
^Cohen, K. M.; Finney, S. C.; Gibbard, P. L.; Fan, J.-X. (January 2020)."International Chronostratigraphic Chart"(PDF). International Commission on Stratigraphy. Retrieved23 February 2020.
^Sutcliffe, Antony J. (1986).On the track of ice age mammals (Reprinted with amendments ed.). London: British Museum (Natural History).ISBN978-0-565-00869-7.
^Olaf Thalmann; Angela R. Perri (2018). "Palaeogenomic Inferences of Dog Domestication". In Lindqvist, C.; Rajora, O. (eds.).Palaeogenomics. Population Genomics. Springer, Cham. pp. 273–306.doi:10.1007/13836_2018_27.ISBN978-3-030-04752-8.
^A. E. Sanders, R. E. Weems & L. B. Albright III (2009).Formalization of the mid-Pleistocene "Ten Mile Hill beds" in South Carolina with evidence for placement of the Irvingtonian-Rancholabrean boundary. Museum of Northern Arizona Bulletin (64:369–375).
^D. E. Savage (1951).Late Cenozoic vertebrates of the San Francisco Bay region. University of California Publications; Bulletin of the Department of Geological Sciences (28:215–314).
^Bell, C. J. (2004). "The Blancan, Irvingtonian, and Rancholabrean mammal ages". In Woodburne, M. O. (ed.).Late Cretaceous and Cenozoic Mammals of North America: Biostratigraphy and Geochronology. New York: Columbia University Press. pp. 232–314.ISBN0-231-13040-6.
^van der Kaars, W. A. (1 June 1991). "Palynology of eastern Indonesian marine piston-cores: a Late Quaternary vegetational and climatic record for Australasia".Palaeogeography, Palaeoclimatology, Palaeoecology.85 (3):239–302.Bibcode:1991PPP....85..239V.doi:10.1016/0031-0182(91)90163-L.ISSN0031-0182.
Ehlers, J., and P.L. Gibbard, 2004a,Quaternary Glaciations: Extent and Chronology 2: Part II North America. Elsevier, Amsterdam.ISBN0-444-51462-7
Ehlers, J., and P L. Gibbard, 2004b,Quaternary Glaciations: Extent and Chronology 3: Part III: South America, Asia, Africa, Australia, Antarctica.ISBN0-444-51593-3
Frison, George C.,Prehistoric Human and Bison Relationships on the Plains of North America, August 2000, International Bison Conference, Edmonton, Alberta.
Gillespie, A. R., S. C. Porter, and B. F. Atwater, 2004,The Quaternary Period in the United States. Developments in Quaternary Science no. 1. Elsevier, Amsterdam.ISBN978-0-444-51471-4
Mangerud, J., J. Ehlers, and P. Gibbard, 2004,Quaternary Glaciations : Extent and Chronology 1: Part I Europe. Elsevier, Amsterdam.ISBN0-444-51462-7
Sibrava, V., Bowen, D. Q., and Richmond, G. M., 1986,Quaternary Glaciations in the Northern Hemisphere, Quaternary Science Reviews. vol. 5, pp. 1–514.
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