Did Humans Cause the Glacial Extinctions? By: Alex Bauman

Do you think that humans are the sole reason for the extinctions?

Scientists Continue to Disagree Changes in habitat Hunting by humans Combination of both reasons

Woolly Mammoths The fossil record puts the mammoth at 300 kyr - 3.7 kyr on Wangle Island in the Atlantic Ocean. The change in climate from between 126 kyr - 21 kyr - 6 kyr led to a change in the vegetation and reduced the mammoth’s steppe-tundra habitat. Like during the last interglacial period, mammoths would have gone into small pockets of populations making them easier targets for humans hunting.

Giant Deer Thrived from 400, 000 years -male skeleton with antlers from Kamyshlov (6.9 kyr) -male skull with cervical vertebrae from Redut river (7.0kyr) Living in what is now Russia these two giant deer could have survived in the Urals or Western Siberia. For a explanation of their extinction : the population could have been forced onto the plains from the Ural foothills due to the vegetation changes where they would have been gullible to hunting pressure.

Saber Tooth Cat Two of the largest terrestrial carnivores that lived during the Pleistocene were the saber toothed cat, Smilodon fatalis, and the American Lion, Panthera atrox. 1993 – a study was made that looked at the broken teeth of fossils and considered that evidence that they were chewing bones from kills 2012 – a study covered same things but came to the conclusion that there was no difference in the use of carcasses compared to different times

My Opinion For many mammals of the Last Glacial Period, they would have shrunk in population size during the Last Interglacial Period (126 kyr) just like they are doing now. The only thing different now compared to then was that humans were present. Without climate change changing the location of their food and habitat I find it hard to believe that we would have caused any great difference in population sizes of the large mammals.

Questions?

References Ananthaswamy, A. (2010). Bye-bye mammoth, hello hotter world. New Scientist, 207(2768). DeSantis, L.R.G., Schubert, B.W., Scott, J.R., & Ungar, P.S. (2012). Implications of diet for the extinction of saber-toothed cats and American lions. PLoS ONE, 7(12), 1-9. Haynes, G. (2002). The catastrophic extinction of North American mammoths and mastodonts. World Archaeology, 33(3), 391-416. Nogues-Bravo, D., Rodriguez, J., Hortal, J., Batra, P., & Araujo, M.B. (2008). Climate change, humans, and the extinction of the woolly mammoth. PLoS Biology, 6(4), 685-692. Stuart, A.J., Kosintsev, P.A., Higham, T.F.G., & Lister, A.M. (2004). Pleistocene to Holocene extinction dynamics in giant deer and woolly mammoth. Nature, 431, 684-689.