Contributions of genetic and non-genetic sources to variation in cooperative behaviour in a cooperative mammal

The evolution of cooperative behaviour is a major area of research among evolutionary biologists and behavioural ecologists, yet there are few estimates of its heritability or of its evolutionary potential and long-term studies of identifiable individuals are required to disentangle genetic and non-genetic components of cooperative behaviour. Here we use long-term data on over 1800 individually recognisable wild meerkats (Suricata suricatta) collected over 30 years and a multi-generational genetic pedigree to partition phenotypic variation in three cooperative behaviours (babysitting, pup feeding and sentinel behaviour) into individual, additive genetic and other sources, and to assess their repeatability and heritability. In addition to strong effects of sex, age and dominance status, we found significant repeatability in individual contributions to all three types of cooperative behaviour both within and across breeding seasons. Like most other studies of the heritability of social behaviour, we found that the heritability of cooperative behaviour was low. However, our analysis suggests that a substantial component of the repeatable individual differences in cooperative behaviour that we observed was a consequence of additive genetic variation. Our results consequently indicate that cooperative behaviour can respond to selection, and suggest scope for further exploration of the genetic basis of social behaviour.