A genetic analysis of breeding success in the cooperative meerkat (Suricata suricatta)

Measurement of reproductive skew in social groups is fundamental to understanding the evolution and maintenance of sociality, as it determines the immediate fitness benefits to helpers of staying and helping in a group. However, there is a lack of studies in natural populations that provide reliable measures of reproductive skew and the correlates of reproductive success, particularly in vertebrates. We present results of a study that uses a combination of field and genetic (microsatellite) data on a cooperatively breeding mongoose, the meerkat (Suricata suricatta). We sampled 458 individuals from 16 groups at two sites and analyzed parentage of pups in 110 litters with up to 12 microsatellites. We show that there is strong reproductive skew in favor of dominants, but that the extent of skew differs between the sexes and between different sites. Our data suggest that the reproductive skew arises from incest avoidance and reproductive suppression of the subordinates by the dominants.