The term used to describe animals that copulate with several different partners within a short time span. Although the pair bond in Purple Martins is monogamous, males are highly promiscuous and will copulate (often forcibly) with any fertile female they can. Recent evidence suggests that subadult female martins are also highly promiscuous, "wanting" their eggs to be fertilized by older, genetically superior males. Compare with "Polygamous" and "Monogamous."