Reflectance spectra and mating patterns support intraspecific mimicry in the colour polymorphic damselfly Ischnura elegans
Résumé
Coexistence of female colour morphs in animal populations is often considered
the result of sexual conflict, where polymorphic females benefit from reduced male sexual
harassment. Mate-searching males easily detect suitable partners when only one type of
female is present, but become challenged when multiple female morphs coexist, which
may result in frequency-dependent mate preferences. Intriguingly, in damselflies, one
female morph often closely resembles the conspecific male in body coloration, which has
lead to hypotheses regarding intra-specific male-mimicry. However, few studies have
quantitatively evaluated the correspondence between colour reflectance spectra from males
and male-like females, relying instead on qualitative visual assessments of coloration.
Using colour analyses of reflectance spectra, we compared characteristics of the body
coloration of ontogenetic male and female colour morphs of the damselfly Ischnura elegans.
In addition, we evaluated whether males appear to (1) discriminate between
immature and mature female colour morphs, and (2) whether male-like females experience
reduced male mating attention and low mating frequencies as predicted from