The sociobiology of male–infant interactions in Barbary macaques, Macaca sylvanus.
Animal Behaviour 51 (1): 155-170. https://doi.org/10.1006/anbe.1996.0013.
Arbeit durchgeführt im Affenberg Salem.
Unlike most Old World monkeys, male Barbary macaques frequently associate with and care for infants shortly after birth. Three functional hypotheses have been proposed to explain male–infant interactions in this and other species. (1) The ‘paternal investment hypothesis’ proposes that males invest in their own progeny or otherwise related infants, (2) the ‘mating effort hypothesis’ proposes males care for infants to increase their access to mothers, and (3) the ‘agonistic buffering hypothesis’ proposes that males use infants to regulate their relations with other males. These hypotheses were tested using data on male–infant interactions, paternity and sexual behaviour obtained during a longitudinal study on Barbary macaques living in a large outdoor enclosure. Paternity of 91 infants was determined by DNA fingerprinting. Hypothesis 1 was not supported, because males did not preferentially interact with closely related infants. Similarly, hypothesis 2 was not supported because male caretakers were not more likely to sire the next infant of the mother than non-caretakers. Hypothesis 3 was supported because (1) the direction of at least one type of triadic interactions was significantly biased towards higher-ranking males, (2) the patterning of triadic interactions was strongly dependent on the rank distance between the males, and (3) interaction frequency increased significantly during periods of high inter-male tension. While kin relations were unimportant, the use of infants familiar with the opponent suggests that males make use of their knowledge of relationships between other group members. Beyond agonistic buffering, triadic interactions may serve an important function in coalition formation.