Quirks & Quarks

Sexual Cannibalism - When Dates Become Dinner

Mantids will deceptively use sexual scents when extremely hungry, if interested in a meal instead of a mate.
This mantid male has lost his head over the female. (Dr. Kate Barry)
The praying mantis and its relatives in the mantid family are well known for sexual cannibalism. The male is often eaten by the female as he attempts to mate with her. In fact, he's able to mate even while he's being devoured, which makes it all worth it - at least in evolutionary terms.

But this leads to a certain temptation for the females. Why not summon males whenever she's hungry, rather than only when she's interested in mating? 

Dr. Kate Barry from the Biological Sciences Department of Macquarie University in Sydney, Australia, tested this idea - known as the Femme Fatale hypothesis. She found that females are, in fact, quite restrained in using this advantage, and only summon males exclusively for dinner when they are on the edge of starvation.

​Related Links

- Paper in Proceedings of the Royal Society B:
ABC Science story
Science news story

 

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