Sociobiology of Rape in Mallards (Anas platyrhynchos): Responses of the Mated Male.
Male mallards respond to rapes of their mate by intervening aggressively against the rapist or rapists, by attempting to force a copulation with the rape victim, or both. Aggressive intervention is more likely against a solitary male than against a group, and forced copulations are more likely immediately after a rape and especially when the rape appears to have been successful. This behavior pattern reflects, strategies consistent with maximizing individual male fitness.
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