1 Amstrup, S.C., G.M. Durner, I. Stirling, N. Lunn, and F. Messier. 2002. Movements and distribution of polar bears in the Beaufort Sea. Canadian Journal of Zoology. 78:948-966.
2 Smith, T.S., S.T. Partridge, S.C. Amstrup, and S. Schliebe. 2007. Post-Den Emergence Behavior of Polar Bears (Ursus maritimus) in Northern Alaska. Arctic. 60: 187-194.
3 Messier, F., M.K. Taylor, and M.A. Ramsay. 1994. Denning ecology of polar bears in the Canadian Artic archipelago. Journal of mammalogy. 75:420-430.
4 Hansson, R. and J. Thomassen. 1983. Behavior of polar bears with cubs in the denning area. International Conference on Bear Research and Management. 5:246-254.
5 Watts, P.D., N.A. Oritsland, and R.J. Hurst. 1987. Standard Metabolic Rate of Polar Bears Under Stimulated Denning Conditions. Physiological Zoology. 60:687-691.
6 Stirling, I, and A.E. Derocher. 1993. Possible impacts of Climate Warming on Polar Bears. Arctic. 46:240-245.
7 Atkinson, Stephen N., Ralph A. Nelson, and Malcolm A. Ramsay. Changes in the Body Composition of Fasting Polar Bears (Ursus maritimus): The Effect of Relative Fatness on Protein Conservation. 1995. Physiological Zoology. 69:301-316.
8 Amstrup, S.C. 2003. "The Polar Bear - Ursus maritimus." Chapter 27 in Wild Mammals of North America: biology, management, and conservation. Edited by G.A. Feldhamer, B.C. Thompson, and J.A. Chapman. John Hopkins Univeristy Press, Baltimore. 587-610.
9 "Polar bear Ursus Maritimus - Detailed Physiology Notes (LiteratureReports)." Polar Bear Ursus Maritimus. Web. 20 Oct. 2011.<http://wildlife1.wildlifeinformation.org/s/0MCarnivor/ursidae/ursus/Ursus_maritimus/10ursus_maritimusdetphy.html>.
10 Folk, G.E., Jr., M.A. Folk, and J.J. Miner. 1972. Physiological condition of three species of bears in winter dens. Bears: their biology and management. International Union for the Conservation of Nature, Morges, Switzerland. New Ser. 23:107-125.
11 "San Diego Zoo's Animal Bytes: Polar Bear." Welcome to the San Diego Zoo. Web. 20 Oct. 2011. <http://www.sandiegozoo.org/animalbytes/t-polar_bear.html>.
12 "Central Park Zoo Bear Euthanized at 25." New York Times. 3 June 2011. <http://www.nytimes.com/2011/06/04/nyregion/polar-bear-at-central-park-zoo-is-euthanized.html>.
13 M. Dorcas, pers. comm.
14 "Physiology." The American Heritage Science Dictionary. Boston: Houghton Mifflin, 2005. Credo Reference. 12 June 2007. Web. 30 Sept. 2011. <http://www.credoreference.com/entry/hmsciencedict/physiology>.
15"Physiology." Illustrated Dictionary of Science, Andromeda. London: Andromeda, 1988. Credo Reference. 1 Jan. 2002. Web. 30 Sept. 2011. <http://www.credoreference.com/entry/andidsci/physiology>.
16 Donald W. Linzey, "Bear," in AccessScience,©McGraw-Hill Companies, 2008, http://ezproxy.lib.davidson.edu:3505.
17 Scholander, P.F., R. Hock, V. Walters, and L. Irving. 1950. Adaptation to cold in arctic and tropical mammals and birds in relation to body temperature, insulation, and basal metabolic rate. Biological Bulletin 99:259-71.
18 Shields, G.F. and T.D. Kocher. 1991. Phylogenetic relationships of North American ursids based on analysis of mitochondrial DNA. Evolution 45:218-221.
19 Cronin, M.A., S.C. Amstrup, G.W. Garner, and E.R. Vyse. 1991. Inerspecific and intraspecific mitochondrial DNA variation in North American bears (Ursus). Canadian Journal of Zooloogy. 69:2985-2992.
20 "Phylogenetics." Encyclopedia of the Human Genome. Hoboken: Wiley, 2003. Credo Reference. 2 Feb. 2010. Web. 20 Oct. 2011. <http://www.credoreference.com/entry/wileyhg/phylogenetics>.
21 http://users.tamuk.edu/kfjab02/Biology/Mammalogy/systematics/A6carnivora.htm
22 Regehr, E.V., N.J. Lunn, S.C. Amstrup, and I. Stirling. Effects of Earlier Sea Ice Breakup on Survival and Population Size of Polar Bears in Western Hudson Bay. 2011. The Journal of Wildlife Management. 71:2637-2683.