Top Chimps Tend to Suffer from More Parasites

http://www.sciencedaily.com/releases/2010/12/101208181348.htm

ScienceDaily (Dec. 9, 2010) — A study of chimpanzees has revealed that dominant animals with higher testosterone levels tend to suffer from an increased burden of parasites.

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"Acquisition and maintenance of high dominance rank often involves frequent aggression, and testosterone has been considered the quintessential physiological moderator of such behavior. However, testosterone also causes suppression of the immune system."

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