Parasites as a Selective Force in Primate Social Systems Evolution

2014 Fiscal Year Final Research Report

• Project/Area Number: 24770232
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Physical anthropology
• Research Institution: Kyoto University
• Principal Investigator: MACINTOSH Andrew 京都大学, 野生動物研究センター, 特定准教授 (30623136)
• Project Period (FY): 2012-04-01 – 2015-03-31
• Keywords: Primatology / Parasitology / Coevolution / International Exchange / Social Network Analysis / Widlife Epidemiology / Disease Ecology / Behavioral Ecology

Outline of Final Research Achievements

This project tested whether parasites are a selective force in primate social systems evolution. Experimental nematode parasite removal from a subset of free-ranging female Japanese macaques on Koshima, Miyazaki, showed that parasites are energetically costly; parasite removal allowed high-ranking females to maintain higher body mass than untreated females when food was abundant. More striking, treated females showed higher breeding success than control females, showing that parasites can constrain breeding potential. My previous work, and modeling done during this study, shows that social networks influence infection risk, so these results show for the first time that chronic nematode parasitism can regulate primate populations and affect social structure, making them a selective force in primate social systems evolution.

Free Research Field

Primatology