Female praying mantises are known well for attacking and cannibalising their mates during or after sexual encounter.

This picture is the fight of male and female peacock mantises, originally from Thailand, in a research of insect biodiversity.

Sexual cannibalism is common amongst praying mantises and some carnivorous invertebrate. The female sometimes does not even recognize that is her husband, so anything moving in her front just make her more appetizing and end up by eating her husband. Some research found that the male just dedicate his body as her meal for passing through some essential amino acids to next offspring. However, there is the secret behind her back. She eats her husband just to make sure that this guy will not get back and mate with her again, so she can have another date with different guys. In the animal kingdom, we could say that this is how female praying mantises gain her genetic diversity to the next offspring.