There are three varieties of monogamy: social monogamy, sexual monogamy, and genetic monogamy.

Social monogamy refers to two partners living together, having sex with each other, and cooperating in acquiring basic resources such as shelter, food and money.
Sexual monogamy refers to two partners remaining sexually exclusive with each other and having no outside sex partners.
Genetic monogamy refers to sexually monogamous relationships with genetic evidence of paternity.

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