A bird that tricks another bird into raising its young. Some brood parasites, including cowbirds and many Old World cuckoos, always breed in this way, laying their eggs in the nests of different species. A variety of other birds, including waterfall, gamebirds, and songbirds, are occasional brood parasites. They lay eggs themselves, but sometimes lay their eggs in the nest of another member of the same species instead 
^Frances, Peter; et al. (2007). Bird: The Definitive Visual Guide. Dorling Kindersley Inc. ISBN1564582957. CS1 maint: Explicit use of et al. (link)
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