Prison sexuality, usually thought of as non-homosexual or situationally-homosexual, shows quite similar dominance traits to those of the apes, creating similar relationship structures. Similar animal-based behaviours are widely understood as being part of human nature, and hence sexual relationships tend to follow universal archetypes, which manifest themselves in all aspects of human culture and behaviour.
In many cases among men, the insertive partner is not viewed as being gay, and the receptive partner (who may not be consenting) is called a woman, or a "punk." In the United States in particular, rape in prisons is a major problem, and may be perpetuated by inmates who do not see themselves as homosexual. A man who has been raped, or who has had receptive intercourse, is often seen as less masculine and hence a target for future rape and other violence.
Among men, the receptive partner may be protected by the insertive partner from fights etc, and some heterosexuals enter relationships for this purpose, or to restrict the number of men they must sleep with.
The incidence of hepatitis in prisons is very high, though this may be due to inmates having used intravenous illegal drugs before arrest, rather than due to sexual behavior.
See also Human sexual behavior
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