1. Gigantism and the Island Rule Tim Schmidt

2. Questions What caused the extinction of gigantism (Pleistocene megafauna)? What are the causes behind the island rule? Is there a link between the extinction of gigantism in animals and the “island rule”?

3. Gigantism (Pleistocene megafauna) Mega Fauna = Big animal Pleistocene era ended around 12,000 years ago with recession of last continental glacier Environmental Changes Overhunting journal.davidbyrne.com

4. Megafauna vs. Humans (Barnosky, 2008)

5. Irish Elk http://tembotime.files.wordpress.com/2011/03/irish-elk.gif Known for large antlers Used for fighting (Only in males) Antlers could reach 3.6 m and weigh almost 40 kg Change of environment led to lack of nutrients (Calcium) Could no longer afford antlers energetically Human hunting http://farm3.static.flickr.com/2222/2146772919_f9461a59d8.jpg

6. Moose vs. Irish Elk (Moen, Pastor, & Cohen, 1999)

7. Island Rule http://online-show.com/wp-content/uploads/2010/05/tropical_island_screensaver1.jpg Small vertebrates -  Gigantism Competitive Release Large vertebrates -  Dwarfism Lack of nutrition Increased competition New predators

8. Case Study (Lomolino, 2005)

9. Conclusion Similarities between Extinction of Megafauna and Island Rule o Both have nutritional constraints o New predator relationships o Increased competition

10. Works Cited Barnosky, A, D. (2008). Megafauna biomass tradeoff as a driver of quaternary and future extinctions. PNAS, 105(1), 11543– 11548. Lomolino, M.V. (1985). Body size of mammals on islands: the island rule reexamined. The American Naturalist, 125(2), 310-316. Lomolino, M.V. (2005). Body size evolution in insular vertebrates: generality of the island rule. Journal of Biogeography, 32, 1683-1699. McClain, C.R., Boyer, A.G., & Rosenberg, G. (2006). The island rule and the evolution of body size in the deep sea. Journal of Biogeography, 33, 1578-1584 Meiri, S., Dayan, T., & Simberloff, D. (2004). Body size of insular carnivores: little support for the island rule. The American Naturalist, 163(3), 469-479. Millien, V., & Damuth, J. (2004). Climate change and size evolution in an island rodent species: new perspectives on the island rule. Evolution, 58(6), 1353-1360. Moen, R.A., Pastor, J., & Cohen, Y. (1999). Antler growth and extinction of irish elk. Evolutionary Ecology Research, 1, 235- 249. Raia, P., & Meiri, S. (2006). The island rule in large mammals: paleontology meets ecology. Evolution, 60(8), 1731-1742.

11. Questions? http://www.anaspides.net/images/anaspides_net/earth_life_sciences/megafauna_extinction/m_prisca_and_friend.jpg