Lobsters hate other lobsters.
In fact, they only interact with other lobsters for two reasons - fighting and fucking.
Every male lobster fight is a status fight. The winning lobster increases its status. It takes ownership of the best shelter. It exudes hormones that attract females. This engenders the mating interaction.
When mating, female lobsters molt their shells. They are soft and defenceless. If they are pregnant, male lobsters will kill them if they find them.
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