Sexual coercion

Sexual coercion in animals is the use of violence, threats, harassment, and other tactics to help them forcefully copulate. Such behavior has been compared to sexual assault, including rape, among humans.

In nature, males and females usually differ in reproductive fitness optima. Males generally prefer to maximize their number of offspring, and therefore their number of mates; females, on the other hand, tend to care more for their offspring and have fewer mates. Because of this, there are generally more males available to mate at a given time, making females a limited resource. This leads males to evolve aggressive mating behaviors which can help them acquire mates.

Sexual coercion has been observed in many species, including mammals, birds, insects, and fish. While sexual coercion does help increase male fitness, it is very often costly to females. However, in spite of these costs, a possible benefit to the females is a chance to test the stamina of the males, so that only those with "good genes" will father their offspring. Sexual coercion has been observed to have consequences, such as intersexual coevolution, speciation, and sexual dimorphism.

Harassment is a technique used by males of many species to force females to submit to mating. It has been observed in numerous species, including mammals, birds, insects and fish. Aggression and harassment have been documented in the males of guppies (Poecilia reticulata),bottlenose dolphins (Tursiops aduncus), botos (Inia geoffrensis), dusky dolphins (Lagenorhynchus obscurus), Hector's dolphins (Cephalorhynchus hectori), grizzly bears, polar bears, and ungulates. It is also seen in Chinook salmon (Oncorhynchus tshawytscha), red-spotted newts (Notophthalmus viridescens), and seed-eating true bugs (Neacoryphus spp.). Furthermore, it is prevalent in spider monkeys, wild Barbary macaques (Macaca sylvanus) and many other primates.

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