Climate Change Research Today is a free monthly online journal that collates and summarizes the latest research about Climate Change, including details on causes, effects, impact, facts, myths, information. | ||||||||
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Asynchronous extinction of late Quaternary sloths on continents and islands.Steadman DW, Martin PS, MacPhee RD, Jull AJ, McDonald HG, Woods CA, Iturralde-Vinent M, Hodgins GW Florida Museum of Natural History, University of Florida, Gainesville, FL 32611, USA. dws@flmnh.ufl.edu Whatever the cause, it is extraordinary that dozens of genera of large mammals became extinct during the late Quaternary throughout the Western Hemisphere, including 90% of the genera of the xenarthran suborder Phyllophaga (sloths). Radiocarbon dates directly on dung, bones, or other tissue of extinct sloths place their "last appearance" datum at approximately 11,000 radiocarbon years before present (yr BP) or slightly less in North America, approximately 10,500 yr BP in South America, and approximately 4,400 yr BP on West Indian islands. This asynchronous situation is not compatible with glacial-interglacial climate change forcing these extinctions, especially given the great elevational, latitudinal, and longitudinal variation of the sloth-bearing continental sites. Instead, the chronology of last appearance of extinct sloths, whether on continents or islands, more closely tracks the first arrival of people. Published 17 August 2005 in Proc Natl Acad Sci U S A, 102(33): 11763-8.
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