Host: Primate Society of Japan
Hygiene encompasses behaviours that maintain individuals and their environments clean to prevent infectious disease. Hygienic practices are human universals, but less is known about such behaviours in other species. While diverse strategies for avoiding parasites have been proposed, and despite the ubiquity of faecal-oral parasites, feeding-related infection-avoidance strategies remain poorly understood in other vertebrates. We tested through experimentation and observation whether food manipulation behaviours and faeces avoidance in a non-human primate could reflect hygienic tendencies that reduce parasite burdens. We show that collective food-related risk-sensitivities, manifest as tendencies to process food items before consumption and avoid faeces, are correlated negatively with intensity of infection by faecal-oral geohelminths in Japanese macaques in their natural habitat. This behavioural suite may therefore reflect hygienic tendencies, providing a mechanism of behavioural immunity with implications for the evolution of health maintenance strategies in humans.
