This usually excludes the case of birds feeding brood parasites.
The behaviour has been of theoretical interest since it appears to be provide little evolutionary benefit to the feeding bird.
[1][2][3][4] Some researchers have suggested that it is mainly male birds that are lured into feeding a fledgling that begs.
Several situations have been suggested that lead to this including:[2] Shy (1982) listed 65 species of birds involved in interspecific feeding.
Riedman (1982) listed 150 species of birds that adopted young that did not belong to themselves.