Offspring Protection by Male Mandrills, Mandrillus Sphinx

Most mammals are characterized by a lack of parental care by the male sex. This is particularly true in highly polygynous, sexually selected species and species in which fathers remain only weakly associated with their offspring. Here we report observations suggesting the existence of male parental care in the mandrill (Mandrillus sphinx, Primates: Cercopithecinae), one of the most sexually dimorphic mammal species known and a species in which, in the wild, males reside in social groups solely for the breeding season. Adult males in three captive groups exhibited aggressive, protective behavior when definite or likely offspring became involved in agonistic confrontations with individuals outside of the group. Males were observed to abandon feeding opportunities, sexual consorts, and allogrooming sessions to intervene on behalf of their threatened offspring. In one of the three groups, the male was occasionally removed, leaving only his mate and their two juvenile offspring; during these periods (when support from their father was unavailable) each of the juveniles initiated significantly fewer extra-group agonistic disputes. A fourth group was studied in which the male was unrelated to the two juveniles, and in this group the male failed to protect the juveniles from outside threats. Although these observations of paternal care were detected across varying social and ecological conditions, it is unclear to what extent they apply in the wild.