sexual sadism, necrophilia (sex with corpses), zoophilia (sex with animals), coprophilia (sex involving defecation), can be seen as having species survival value and thus do "not warrant being excluded from the list of the `so-called natural forms of human sexual behavior Gardner, R.A. (1992).

In addition, Gardner proposes that many different types of human sexual behavior, including pedophilia, sexual sadism, necrophilia (sex with corpses), zoophilia (sex with animals), coprophilia (sex involving defecation), can be seen as having species survival value and thus do "not warrant being excluded from the list of the `so-called natural forms of human sexual behavior.'"

See,  True and False Accusations of Child Sex Abuse . Cresskill, NJ: Creative Therapeutics. (pp. 18-32)

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