http://www.newsweek.com/female-dragon-flies-fake-death-avoid-sex-evolution-591494
By Hannah Osborne On 4/28/17
In order to avoid males of the species bothering them for sex, female dragonflies fake their own deaths, falling from the sky and lying motionless on the ground until the suitor goes away.
A study by Rassim Khelifa, a zoologist from the University of Zurich is the first time scientists have seen odonates feign death as a tactic to avoid mating, and a rare instance of animals faking their own deaths for this purpose. Odonates is the order of carnivorous insects that includes dragonflies and damselflies.
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Khelifa notes there are few instances of animals faking their own deaths, with four others known to science. These include two species of robber fly, the European mantis and the spider species Pisaura mirabilis, where the males fake death in order to avoid being killed after mating. One study describes the females of another species of dragonfly lying motionless—but researchers did not suggest it was faking death.
Over the next few months, Khelifa documented dozens of cases where females would crash land and play dead while being pursued by a male. He also looked at the reproductive behaviour of A. juncea to try to work out why females would do this.
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Even though it is a risky strategy, faking death appears to help females survive longer and produce more offspring by avoiding coercion.
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