Abstract # 166:

Scheduled for Sunday, September 18, 2011 07:00 PM-09:00 PM: Session 23 (Salon G (Sixth Floor)) Poster Presentation


M. S. McCarthy, C. E. Finch and C. B. Stanford
University of Southern California, Department of Biological Sciences, 3616 Trousdale Parkway, AHF 107, Los Angeles, CA 90089, USA

In chimpanzees (Pan troglodytes), the rise to alpha status carries great risk of injury or even death. Despite these risks, being a dominant male can carry benefits as well, including greater access to resources. This study surveyed published data from five long-term field sites and found alpha male chimpanzees lived significantly longer than males who never achieved this status. Adult life expectancy is 34.7 years for alpha males (n = 9), versus 27.6 years for non-alpha males (n = 21; t_y = 2.45, p = .03). Alpha males were deposed at a mean age of 27.6 years. This age matches the life expectancy of non-alpha males, suggesting alpha males live an additional 7 years following demotion compared with their non-alpha counterparts. Data from other nonhuman primates and humans suggests high social status is associated with increased health and longevity. Explanations for heightened longevity in dominant male chimpanzees are speculative but include maternal rank benefits, better resource access, and lower disease prevalence. The evident further life span of former alphas may be interpreted as opposite to the general associations in humans of lower social status with lower life expectancy. This study suggests further investigation is warranted to better understand the relationship between social rank and longevity in chimpanzees.