Chick recognition and acceptance: a weakness in magpies exploited by the parasitic great spotted cuckoo |
| |
Authors: | Manuel Soler Juan Gabriel Martinez Juan Josf Soler Anders Pape Møller |
| |
Institution: | (1) Departamento de Biología Animal y Ecologia, Facultad de Ciencias, Universidad de Granada, E-18071 Granada, Spain;(2) Department of Population Biology, Zoological Institute, University of Copenhagen, Universitetsparken 15, DK-2100 Copenhagen Ø, Denmark |
| |
Abstract: | Hosts of brood parasites have evolved the ability to discriminate non-mimetic and even mimetic eggs, but not non-mimetic chicks. Here we demonstrate that the great spotted cuckoo Clamator glandarius does not provide its magpie Pica pica host with a super-normal stimulus that helps to avoid recognition, because single cuckoo chicks introduced into otherwise unparasitized magpie nests are not fed at a higher frequency than single magpie chicks introduced to parasitized magpie nests. Another series of experiments demonstrated that magpies have the ability to discriminate cuckoo chicks, mainly when these are introduced at the end of the nestling period, and especially when the cuckoo chick together with a magpie chick is presented to adult magpies outside the nest. This supports the idea that cuckoos exploit the obligatory reaction of magpies to feed all young that have been hatched in their nests and whose signatures they have learnt. Furthermore, the experimental cuckoo chicks in parasitized magpie nests were more likely to be accepted than they were in non-parasitized nests. This supports the hypothesis that magpies may learn to recognise their own nestlings as those present in the nest and may indicate that a comparison between cuckoo and magpie nestlings is the basis of discrimination. |
| |
Keywords: | Brood parasitism Clamator glandarius Chick recognition Pica pica Supernormal stimulus |
本文献已被 SpringerLink 等数据库收录! |
|