Effects of helpers on feeding of nestlings in the Grey-crowned Babbler (Pomatostomus temporalis)

Provisioning of nestlings by dunnocks, Prunella modularis, in pairs and trios compensation reactions by males and females

“…For example, in cooperatively breeding grey-crowned babblers Pomatostomus temporalis both parents invest less if helpers contribute to feeding (Brown et al 1978), enabling the parents to have more broods per year (Brown et al 1982). Other studies have found that helper investment simply adds to the normal work rate of a pair and increases nestling survival, e.g.…”

The role of helpers in feeding chicks in cooperatively breeding green (red-billed) woodhoopoes

“…The costs and benefits of helping behaviour are of particular interest to evolutionary biologists because of the importance of this behaviour in determining the applicability of the concept of inclusive fitness in vertebrates (Hamilton 1964;Brown et al 1978;Brown 1987). One of the most conspicuous and quantifiable types of assistance is the feeding of chicks, a behaviour which is found in most cooperatively breeding bird species.…”

Territoriality, Prospecting, and Dispersal in Cooperatively Breeding Micronesian Kingfishers (Todiramphus Cinnamominus Reichenbachii)

“…Covert reproduction by delayed dispersers during forays would provide evidence of a previously undocumented pathway to fi tness, and suggests that delaying and foraying may be more of an alternative life-history strategy than simply "making the best of a bad situation," as some 391 have suggested (e.g., Emlen 1997). Further, if covert extraterritorial helper reproduction is common in many species, the behavior even has the potential to alter perceptions about the costs and benefi ts of cooperative breeding and delayed dispersal, which have been debated for several decades (Skutch 1935, Brown et al 1978, Vehrencamp 1980, Brown 1987, Stacey and Koenig 1990, Gerlach and Bartmann 2002, Haydock and Koenig 2003, Griffi n et al 2003. A molecular genetic investigation of parentage in Micronesian Kingfi shers has the potential to lend insight into this phenomenon.…”