Complex relationship between multiple measures of cognitive ability and male mating success in satin bowerbirds, Ptilonorhynchus violaceus

Many animal species have complex cognitive abilities previously assumed to be limited to humans. Explanations for how these abilities evolved have focused on ways in which cognitive performance may influence survival, such as solving ecological problems or navigating complex social environments. However, sexual selection (differences in the reproductive success of individuals) can also lead to the evolution of complex traits. This could occur, for example, if females prefer males with better cognitive ability. A common assumption of models of female choice for male cognitive ability is that performance scores on different cognitive tasks are intercorrelated. In the present study, we evaluated performance of male satin bowerbirds on six cognitive tasks. Although we found little intercorrelation amongst males' performance scores of these tasks, males with better scores for two integrative measures of these cognitive tasks had higher mating success, which is a good indicator of reproductive success in this species. In addition, a multiple regression analysis suggested that performance on most cognitive tasks independently predicted mating success. Our results point to an important link between sexual selection and cognitive ability that has not been well appreciated and appears to be quite complex.