Character displacement in male traits though learned female preferences
How do learned mate preferences affect the development of reproductive isolation? This I study in a damselfly species complex (the genus Calopteryx).
Melanin wing spots in Calopteryx damselflies are one of the major phenotypic differences between the males of the various species. These melanin wing spots are a classic example of a character mediating reproductive isolation . Two common species in Europe, C. splendens and C. virgo have males with partly melanised and fully melanised wings, respectively. Females of these two species also differ in wing coloration although they show much less pronounced wing differentiation. The male wing spots are targets of natural selection through avian predation and inter and intra sexual selection. Wing spot size is used by females as a species recognition cue, where females in allopatric populations prefer larger wing spots, but females in sympatric populations prefer wing spots that are within their species’ range.
In a pilot study, Calopteryx females learned to reject heterospecific males after having experience with those males. This summer, we will investigate if they learned to discriminate between males on the basis of their wingspots. Also, why did they learn to reject heterospecific males: what went wrong in that courtship?
This will help us understand what the exact species differences are that females pay attention to, and how they learn about them.