Interspecific parasitic chicks are usually fed more than the smaller host young with whom they share the nest. This could he due to parasitic chicks having evolved exaggerated features that are preferred by the adults to the features present in their own young (the supernormal stimulus hypothesis). Alternatively, the success of parasitic chicks could be due to them being better competitors. We tested these hypotheses by studying the interaction between brown-headed cowbird chicks, Molothrus ater, and a common small host, the yellow warbler, Dendroica petechia. Parasitic chicks begged more intensively than the host's young and received most of the feeds. The relative height reached by the begging chicks of both species was the most important variable in determining their feeding success. Being larger and begging intensively, brown-headed cowbirds were better able to reach higher than the host's young, but at equal heights parasitic chicks were no better than the hosts young at gaining feeds. It is suggested that the success of the brown-headed cowbirds when parasitizing yellow warblers is due to them physically out-competing the smaller young of their hosts, and not to them evoking a stronger response from the hosts by being a supernormal stimulus.
Documento: | Artículo |
Título: | Nestling competition, rather than supernormal stimulus, explains the success of parasitic brown-headed cowbird chicks in yellow warbler nests |
Autor: | Lichtenstein, G.; Sealy, S.G. |
Filiación: | Laboratorio Biologia Comportamiento, IBYME Vuelta de Obligado 2490, (1428) Buenos Aires, Argentina |
Palabras clave: | Begging; Brood parasitism; Cowbird; Supernormal stimulus; begging behaviour; brown-headed cowbird; interspecific competition; nestling competition; parasitic bird; yellow warbler; animal behavior; animal experiment; article; bird; body size; competition; feeding behavior; height; nonhuman; parasitism; priority journal; Animalia; Aves; Dendroica petechia; Dendroica petechia; Molothrus ater; Molothrus ater |
Año: | 1998 |
Volumen: | 265 |
Número: | 1392 |
Página de inicio: | 249 |
Página de fin: | 254 |
DOI: | http://dx.doi.org/10.1098/rspb.1998.0289 |
Título revista: | Proceedings of the Royal Society B: Biological Sciences |
Título revista abreviado: | Proc. R. Soc. B Biol. Sci. |
ISSN: | 09628452 |
CODEN: | PRLBA |
Registro: | https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_09628452_v265_n1392_p249_Lichtenstein |