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Q Why do some animals eat their mate? A

‘Sexual cannibalism’ –the act of eating one’s mate before, during or after mating – most often occurs in spiders and insects, but also in snails and crustaceans. Although reverse sexual cannibalism has been seen in spiders, females are the usual culprits. Several theories attempt to explain the behaviour, including: adaptive foraging, in which females assess and opt for the male’s nutritional value over his mate potential; aggressive spillover, which suggests the more hostile a female is towards prey, the more likely she’ll eat mates; mistaken identity, where females failing to recognise courting males attack and eat them. The behaviour may have evolved due to differences in the reproductive interests of females and males.