Digest: Evolution of redirected help in a viscous population.

Abstract

When broods fail, parents may assist neighbours' offspring, a behaviour called redirected helping that is observed in many species. Flatrès and Wild (2024) used inclusive fitness models to study this behaviour. They showed that redirected helping can evolve in viscous populations, where individuals stay near their birthplace, increasing relatedness and competition among neighbours, especially when helping costs are low. Life-history traits like survival, dispersal, and brood-failure rates shape this behaviour. Interestingly, survival benefits from helping can outweigh reproductive gains, challenging assumptions and providing fresh insights into cooperative breeding dynamics.