Transcript The Ice Age GIANTS

The Ice Age GIANTS
What wiped them out?
Angela Via
What were some of the giants of the
Pleistocene?
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Irish Elk
Dire Wolf
Giant Ground Sloth
Giant Ape
American Lion
Giant Beaver
Giant Ground Sloth
Smithsonian Museum of
Natural History
Large Mammals
• Larger mammals have a pattern of higher
incidence of biome specialization
• Typically have lower reproductive rates due to
long gestation periods and single births
• Habitats support lower numbers of large
animals than small ones
Two Main “Umbrella” Theories
• Climate
• Human impact
Climate Change?
• Rapid global climate change-not uniform left
“pockets” of suitable environments
• Some species less able to adapt
• Rapid change in fauna
Human Colonization?
• Blitzkreig
• Mass landscape burning
• Disease
Why the debate?
• Model simulations unable to predict
accurately all the conditions that could apply
• Dating of when humans colonized certain
areas difficult to pick apart
• Too many unknowns about the extinct species
Emerging Theories
Synergy
Climate suitable areas for Wooly
Mammoth
Number of kills to drive to
extinction
Interesting tid-bits
• Africa is the only land mass that still contains a
variety of mega fauna
• Africa is typically believed to be the
“birthplace of man”
Future work
• Create a model that can better combine the
reduction of the habitats with various effects
of humans and differentiate between different
scenarios.
References
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Bofarull, A. M., A. A. Royo, M. H. Fernandez, E. Ortiz-Jaureguizar, and J. Morales. 2008. Influence
of continental history on the ecological specialization and macroevolutionary processes in the
mammalian assemblage of South America: Differences between small and
large mammals. Bmc
Evolutionary Biology 8:18.
Brook, B. W., and D. Bowman. 2002. Explaining the Pleistocene megafaunal extinctions: Models,
chronologies, and assumptions. Proceedings of the National Academy of Sciences
of the
United States of America 99:14624-14627.
Brook, B. W., and D. Bowman. 2004. The uncertain blitzkrieg of Pleistocene megafauna. Journal
of Biogeography 31:517-523.
Burney, D. A., and T. F. Flannery. 2005. Fifty millennia of catastrophic extinctions after
human
contact. Trends in Ecology & Evolution 20:395-401.
Gillesie, R. 2008. Updating Martin's global extinction model. Quaternary Science Reviews 27:25222529.
Nogues-Bravo, D., J. Rodiguez, J. Hortal, P. Batra, and M. B. Araujo. 2008. Climate change, humans,
and the extinction of the woolly mammoth. Plos Biology 6:685-692.
Pastor, J., and R. A. Moen. 2004. Palaeontology - Ecology of ice-age extinctions. Nature 431:639640.
Yule, J. V., C. X. J. Jensen, A. Joseph, and J. Goode. 2009. The puzzle of North America's Late
Pleistocene megafaunal extinction patterns: Test of new explanation yields unexpected results.
Ecological Modelling 220:533-544.