hypergamy

Hypergamy (colloquially referred to as "marrying up") is the act or practice of marrying a spouse of higher caste or status than oneself.[1] The term is often used more specifically in reference to a perceived tendency among human cultures for females to seek or be encouraged to pursue male suitors that are higher status than themselves, which often manifests itself as being attracted to men who are comparatively older, wealthier or otherwise more privileged than themselves or their current partners.[2] According to economists, females have evolved a preference for higher status males because they offer their prospective children both better genes and greater resources, e.g. food and security. Men, who invest less in their children, have less reason to prefer mates with high social status. Some have even argued that males "marry-down" to ensure that their mates have a higher incentive to remain faithful.[3]

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