Definition: At the end of the last ice age (ca 15,000-10,000 years ago), 85 percent of the large mammals (called megafauna) went extinct. The mass extinctions were not synchronous nor universal, and the reasons proffered for them include (but are not limited to) climate change and human intervention.
Regional Megafauna Extinctions
North America lost about 35 genera of mostly large animals, such as the ground sloth, American lion, dire wolf, and short-faced bear. At the same time 19 genera of birds disappeared; and some animals and birds made radical changes in their habitats, moving north or south.
In Eurasia, 21 taxa disappeared, and as in North America, other species dramatically altered their habitat range. It is clear there, at least, that different animals disappeared at different times within the time frame of the Late Pleistocene, and thus probably for various reasons. North American data is less clear.
Recently, evidence of the survival of several species of giant ground sloth has been discovered in the West Indies, to as late as 5,000 years ago, coincident with the arrival of humans in the region.
Australian Evidence
In Australia, evidence based on AMS radiocarbon dating, Optically Stimulated Luminescence and Uranium/Thorium dating on the QML1396 site in Darling Downs, southeastern Queensland, suggests that megafaunal extinction occurred there over a long period of time. The die-off begins about 75,000 years before human colonization (which is today considered likely 45,000-50,000 years ago). Based on that model, large-bodied mammals died off with a local habitat changes stirred by climate change. If true, then the megafaunal extinction in Australia cannot have been the result of human efforts.
Sources
Grayson, Donald K. 2007 Deciphering North American Pleistocene Extinctions. Journal of Anthropological Research 63(2):185-213.
Price GJ, Webb GE, Zhao J-x, Feng Y-x, Murray AS, Cooke BN, Hocknull SA, and Sobbe IH. 2011. Dating megafaunal extinction on the Pleistocene Darling Downs, eastern Australia: the promise and pitfalls of dating as a test of extinction hypotheses. Quaternary Science Reviews 30(7-8):899-914.
Steadman, David W., et al. 2005 Asynchronous extinction of late Quaternary sloths on continents and islands. Proceedings of the National Academy of Sciences 102(33):11763-11768.
This glossary entry is part of the Dictionary of Archaeology. Any mistakes are the responsibility of Kris Hirst.
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