What conditions have been linked to the practice of polyandry?

In the context of human behavior, polyandry—the marriage of a woman to two or more men at the same time—is generally considered a response to specific, localized conditions rather than a universal social norm.1

Anthropological research suggests that the practice is linked to several environmental and social factors, including:

• Demographic factors: Skewed sex (gender) ratios, high rates of adult male mortality, or significant male absenteeism.1
• Social and economic structure: The nature of social stratification and the group's underlying economic basis, such as reliance on hunting and gathering or specific forms of agriculturalism.1

While polyandry is a rare phenomenon, it has been documented in various societies, including those in the Plateau of Tibet and the Marquesas Islands, as well as in numerous nonclassical societies identified by researchers. In these contexts, the practice may be formal, involving recognized marriage and co-residence, or informal, where multiple men are considered co-fathers and share responsibility for the care of the mother and children.1