Extra-unit paternity of hamadryas baboons (papio hamadryas) in saudi arabia

Sex-biased dispersal and female choice for non-related mates are mechanisms of inbreeding avoidance in animals. In species with limited dispersal of both sexes, the latter mechanism is of greater importance. We investigated a wild population of hamadryas baboons (Papio hamadryas) living in Saudi Arabia and surviving on human garbage. Paternity relationships between adult males and juveniles of three social units were analyzed using 12 loci of tetra-repeat microsatellite DNA. Of 16 juveniles and infants (0-3 years old), 13 were not sired by the leader male of each unit. This extra-unit paternity suggests the possibility that females conducted extra-unit copulations (EUCs) leading to extra-unit fertilizations (EUFs). We discuss this and other possible explanations for the apparent extra-unit paternity, as well as the plausibility of EUFs as a function of inbreeding avoidance in the hamadryas baboon. This is the first molecular study to investigate kin relationships within wild units of hamadryas baboons. © 2003 Taylor & Francis Group, LLC.