Non-Maternal Infant Handling in Wild Formosan Macaques of Mount Longevity, Taiwan.

In this paper, we present quantitative data on how the social network and sex of infants influence allomothering behaviour among wild Formosan macaques, Macaca cyclopis. Using long-term field data collected from the Mount Longevity study site in Kaohsiung (Taiwan), we have tested relevant hypotheses incorporating data on age, rank and reproductive state of infant handlers, and the relationship between handlers and infants. The results support 2 major hypotheses, i.e. those of reciprocity and alliance formation. Nevertheless, neither could account for the observed occurrences of unrelated infant handling by dominant females.