NEPHILID SPIDERS · Nephilid spider phylogenetics as a test for antagonistic coevolution of sexes

Final Activity Report Summary - NEPHILID SPIDERS (Nephilid spider phylogenetics as a test for antagonistic coevolution of sexes)

Genital traits are crucial taxonomically because they vary precisely with species limits. Although genital complexity and diversity probably function to do more than simply transfer sperm, underlying selection pressures remain poorly understood. Historical sexual selection research has focused on pre-mating mechanisms, but has recently shifted towards post-copulatory processes such as sperm competition and cryptic female choice, which may be responsible for much of the observed variation in genital morphology. Sexual conflict promoting antagonistic coevolution has also recently been proposed to cause rapid variation in reproductive traits. In our research programme, funded by the Marie Curie International Reintegration Grant we focused on nephilid spiders, which we propose as models for evolutionary studies. We presented, tested and found significant support for the hypothesis of sexually antagonistic coevolution of genital and sexual behavioural traits in nephilids through a multifaceted research comprising morphological, ethological and molecular phylogenetic research, and ethological experimentation. By demonstrating i) coevolution of male and female sexual traits (both morphological and behavioural), and ii) antagonism between the sexes, we provide the evidence for sexually antagonistic coevolution in nephilid spiders although other mechanisms (e.g. cryptic female choice) cannot be excluded. By focusing on phylogenetic pattern, our data are important in establishing new directions of sexual selection and evolutionary research. The objectives of the project have been met, both scientifically and in terms of a highly successful reintegration of the fellow into European science.

Data: CORDIS, © European Union