Monogamy means one marriage—and four different scientific senses
From Greek monos and gamos, monogamy names a two-person exclusive partnership, yet biologists split social, sexual, and genetic meanings carefully. Human cultures vary widely: few societies demand lifelong exclusive marriage, while many practice serial monogamy across a lifetime.
Context decides whether the word tracks cohabitation, sexual exclusivity, reproductive exclusivity, or legal marriage. Animal studies need the split because pairs may nest together without mating only with each other, or share genes differently than nest labels suggest to observers.
Four overlapping senses are standard: genetic monogamy, backed by paternity evidence; sexual monogamy, with no outside partners; social monogamy, sharing a home, food and child-rearing; and marital monogamy, a marriage of just two people. Biologists and behavioural ecologists usually mean sexual or reproductive exclusivity, whereas social anthropologists mean the social or marital kind. Classical monogamy is the strictest version, in which both marry as virgins, stay exclusive for life and remain celibate after a partner dies. George P. Murdock's Ethnographic Atlas counted 1,231 societies: 186 monogamous, 453 with occasional polygyny, 588 with more frequent polygyny and 4 with polyandry.
Divorce and remarriage produce serial monogamy, several marriages but one legal spouse at a time, and female-headed households in the Caribbean, Mauritius and Brazil with frequent turnover of unmarried partners can also count as plural mating. The genetic record suggests genetic monogamy rose within the last 5,000 to 10,000 years. The Standard Cross-Cultural Sample rates extramarital sex in over 50 pre-industrial cultures, and 2001 surveys in Thailand, Tanzania and Ivory Coast put men's rate at about 16 to 34 percent. Many American surveys lean on convenience samples such as volunteer students or magazine readers, which can badly skew results, and extrapair paternity in people is poorly studied.
Source: Monogamy
