Polygyny Threshold, The

Abstract

The polygyny threshold model (PTM) provides an explanation for the occurrence of polygyny in the animal kingdom – the mating/marriage of one male with multiple females. This model is princi- pally applied to species, including humans, in which males provide/defend resources to provi- sion their mates and offspring. The polygyny threshold refers to the minimum level of inequal- ity in male resource holding, such that a given female’s reproductive success is enhanced by becoming the second mate of a resource-rich and already paired male, rather than the sole mate of a resource-poor unpaired male. Once this threshold is surpassed and there is sufficient inequality, polygyny is predicted to occur.