Linking wing morphology to flight performance in damselflies

What makes a successful damselfly male? Most importantly, he needs to be attractive to females, own a good territory, and avoid being eaten in undue time. All these requirements put selective pressure on wing morphology, although sometimes in opposing directions.
 
Our study system comprises of two damselfly species: Calopteryx splendens (the Banded Demoiselle), and Calopteryx virgo (the Beautiful Demoiselle). Geometric morphometric analyses of wings from Calopteryx damselflies that fell prey to Wagtails (Motacilla sp.) showed that predation poses a number of selection pressures on wing morphology in both species. For C. virgo, there is selection favoring short, but dark wing patches but no selection for a specific wing shape. However, for C. splendens, predation selects for relatively shorter, rounder wings. We now want to measure the effects that such morphological differences have on flight performance, both between and within the species. Mark-and-resighting experiments in the field, combined with geometric morphometric analyses, will tell us about effects on longevity, mating rate, hunting success, and the outcome of territorial fights, among other things.
 
We are also going to have damselflies perform specific flight tests aiming at maneuverability and speed. The wind tunnel with its possibility to observe flights at close range with high-speed cameras and flow visualization will give us even more detailed understanding of the effects that different wing morphology has on the flight performance of an individual. With these results we will eventually be able to compare natural and sexual selection forces on wing morphology.
 

Large wing spots favourable

Large wing spots favourable

Mating pair of Calopteryx splendens. Females prefer males with large wing spots. Photo: Erik Svensson