Maternal social position and survival to weaning in arid‐country vervet monkeys

Abstract

AbstractObjectivesWe consider the relative contributions of maternal rank and sociability to the survival of infant vervet monkeys (Chlorocebus pygerythrus) to nutritional independence (~210 days) in a generally resource‐poor environment.MethodsWe analyzed survival data from 153 infants born to 60 mothers across three free‐ranging troops and 10 yearly birth cohorts at a South African research site experiencing general but variable resource scarcity.ResultsThe population was characterized by a pre‐weaning mortality of 30% (Range: 9%–85%), with a median age at death of 50 days. In addition to the consequences of resource availability, increased infant survival was independently and equivalently positively associated with higher maternal rank and a greater number of maternal spatial partners.DiscussionWe use this outcome to suggest that apparent discrepancies across sites and species in the relative importance of different maternal attributes in determining reproductive outcomes may be resolved by considering more closely local sources of infant mortality.