Sexual desire have been associated with a decline in sexual desire. Though it is not used as medication, the drug methamphetamine has a strong positive effect on many aspects of sexual behaviour, including sexual desire. Sexual desire is said to be influenced by androgens in men and by androgens and estrogens in women. Many studies associate the sex hormone, testosterone with sexual desire. Testosterone is mainly synthesized in the testes in men and in the ovaries in women. Another hormone thought to influence sexual desire is oxytocin. Exogenous administration of moderate amounts of oxytocin has been found to stimulate females to desire
Human male sexuality with a male, and decrease the chance that the female will mate with another male. There are several strategies by which sexual coercion can be achieved. These are harassment, intimidation, and forced copulation (rape). Thornhill and Palmer's "A Natural History of Rape" investigates the evolutionary causes of sexual coercion, particularly of rape, and suggest that such behaviour is a result of sexual selection, rather than Darwinian natural selection. Of ten listed hypotheses, they accepted two reasonable hypotheses: Thornhill and Palmer argue that these two theories are the strongest of the ten for several reasons. For example, both hypothesis argue rape