U. SHEFFIELD (UK)—Male damselflies who hang out warming themselves in sunspots are more successful in the courtship game that their cool counterparts, a new study finds.

Males of the species show elaborate courtship displays that involve high frequency wing-beats directed toward a potential female mate, and previous studies have suggested a female’s choice of mate is based on aspects of courtship display.

It remains unclear whether the courtship display varies between males or is influenced by environmental factors.

Researchers from the University of Sheffield used two new technologies: thermographic imaging and high-speed digital videography to assess the courtship rituals of the damselflies.

Males that had basked in the sun had warmer bodies and were more attractive to the females: they were therefore more likely to copulate than colder males.

Also, females benefit from mating with warmer males, as they have access to the warmest territories, which provides the perfect location for the females to lay their eggs.

Details of the study appear in the journal Behavioral Ecology and Sociobiology.

“This research shows that female mating preference can change over a very short period: a male can become attractive when his territory is in the sunshine but become a wimp when his perch is in the shade,” says Michael Siva-Jothy, professor of animal and plant science.

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