Polygyny in animals

Polygyny (/pəˈlɪdʒɪniː/; from Neo-Greek πολυγυνία from - poly- "many", and gyne "woman" or "wife") is a mating system in which one male lives and mates with multiple females, but each female only mates with a single male. Systems where several females mate with several males are defined either as promiscuity or polygynandry. Lek mating is frequently regarded as a form of polygyny because one male mates with many females, but lek-based mating systems differ in that the male has no attachment to the females with whom he mates, and that mating females lack attachment to one another.

Polygyny is typical of one-male, multi-female groups and can be found in many species including: human, gorilla, elephant seal, red-winged warbler, house wren, hamadryas baboon, common pheasant, red deer, Bengal tiger, Xylocopa varipuncta, Anthidium manicatum and elk. Oftentimes in polygynous systems, females will provide the majority of parental care.

When two animals mate, they both share an interest in the success of the offspring, though often to different extremes. Unless the male and female are perfectly monogamous, meaning that they mate for life and take no other partners, even after the original mate’s death, the amount of parental care will vary. Instead, it is much more common for polygynous mating to happen. Polygynous structures (excluding leks) are estimated to occur in up to 90% of mammals.

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