Male crayfish fake sex with one another to exert dominance and reduce violence, LiveScience has reported. It’s the first such behavior observed in invertebrates.
Among 20 pairs of adult male crayfish tested, pseudocopulation attempts happened in 16 pairs. In 12 of these pairs, the male that was forced into the subordinate role submitted, leading to pseudocopulation nearly identical to normal sexual copulation for seven seconds to about nine minutes. In the other four pairs, the male that was forced into the subordinate role refused all attempts.
In pairs that pseudocopulated, initial levels of aggressive behavior between the males—such as claw attacks or offensive tail flips— declined significantly during the first hour of interaction. All these animals survived over the first 24 hours.
However, in the male pairs that did not pseudocopulate, initial levels of aggression did not slack off during the first hour. Half of the subordinate males were killed, dismembered and partially eaten during the first 24 hours.
Make love not war.