Parentage analyses suggest female promiscuity and a disadvantage for athletic males in the colour-polymorphic lizard Podarcis melisellensis

Although laboratory measurements of whole-animal performance have become a standard tool in evolutionary biology, if and how interindividual variation in performance translates into differential fitness remains poorly understood. Particularly rare are studies that have connected performance to mating and reproductive success in the field. In this study, we use DNA microsatellite parentage analyses to study the fitness gradient in a colour-polymorphic lizard, Podarcis melisellensis. We report on two surprising findings. First, contrary to our expectations, individual sprint speed and bite force capacity correlated negatively, not positively, with male mating and reproductive success. Second, we found an unexpected degree of promiscuity in females. Also, contrary to traditional parental investment theory, the variation in mating success and reproductive success was as high in females as in males. Our results call for a better integration of whole-animal performance and life history traits, and for a reconsideration of the ideas on the likeliness of sexual selection acting on female phenotypes.