n. sexual behavior in which a pair-bonded female mates with a male other than her partner. Only about 10% of bird species that are socially monogamous are genetically monogamous as well (see monogamy). Males whose mates engage in extrapair mating assist in the rearing of the unrelated offspring. Females practicing cuckoldry may benefit from having progeny from genetically higher quality males; for example, female blackbirds that do this have more surviving offspring than monogamous blackbirds.