Abstracts (first author)
Ecology and mating interactions: temperature influences male-female conflict in a colour polymorphic damselfly
Heritable and conspicuous colour polymorphisms have a long research tradition in ecological genetics, and these systems have been used to investigate issues such as negative-frequency-dependent selection (NFDS), maintenance of genetic variation, sexual selection and sexual conflict. Here I will present long-term field observational data and experiments on the evolutionary dynamics of a sexually selected colour polymorphism in the damselfly Ischnura elegans. Three female morphs exist in this species, one of them being a male mimic ("androchrome females"). Androchrome have lower mating rates than other female morphs, suggesting that male mimicry is a female defence against excessive and costly male mating harassment that is detrimental to female fitness. I will present long-term field data from a longitudinal study across multiple populations that show the stability of this female polymorphism and the results of experiments where we have manipulated morph frequencies and densities and evaluated the effects on morph and population fitnesses. I will also present data showing that the male-female mating interactions are environment-dependent and moulded by ambient temperatures, resulting in geographic variation in morph frequencies. Thus, sexual conflict in this system and the benefits of male mimicry is highly context-dependent upon local ecology and the thermal environment.