INVESTIGADORES
MAHLER Bettina
artículos
Título:
Different recognition cues reveal the decision rules used for egg rejection by hosts of a variably mimetic avian brood parasite
Autor/es:
DE LA COLINA, M. A.; POMPILIO, L.; HAUBER, M. E.; REBOREDA, J.C.; MAHLER, B.
Revista:
ANIMAL COGNITION
Editorial:
SPRINGER HEIDELBERG
Referencias:
Lugar: HEIDELBERG; Año: 2012 vol. 15 p. 881 - 889
ISSN:
1435-9448
Resumen:
Brood parasitism imposes several fitness costs
on the host species. To reduce these costs, hosts of avian
brood parasites have evolved various defenses, of which
egg rejection is the most prevalent. In the face of variable
host-parasite mimicry and the costs of egg discrimination
itself, many hosts reject only some foreign eggs. Here, we
experimentally varied the recognition cues to study the
underlying cognitive mechanisms used by the Chalk-browed
Mockingbird (Mimus saturninus) to reject the white
immaculate eggs laid by the parasitic Shiny Cowbird
(Molothrus bonariensis). Immaculate eggs are the only
parasite eggs rejected by this host, as it accepts all polymorphic,
spotted eggs laid by cowbirds. Using a withinbreeding
pair experimental design, we tested for the salience
of spotting, UV reflectance, and brightness in eliciting
rejection. We found that the presence of spotting
significantly decreased the probability of rejection while
increments in brightness significantly increased rejection
frequencies. The cognitive rules underlying mockingbird
rejection behavior can be explained by a decision-making
model which predicts changes in the levels of rejection in
direct relation to the number of relevant attributes shared
between host and parasite eggs.Mimus saturninus) to reject the white
immaculate eggs laid by the parasitic Shiny Cowbird
(Molothrus bonariensis). Immaculate eggs are the only
parasite eggs rejected by this host, as it accepts all polymorphic,
spotted eggs laid by cowbirds. Using a withinbreeding
pair experimental design, we tested for the salience
of spotting, UV reflectance, and brightness in eliciting
rejection. We found that the presence of spotting
significantly decreased the probability of rejection while
increments in brightness significantly increased rejection
frequencies. The cognitive rules underlying mockingbird
rejection behavior can be explained by a decision-making
model which predicts changes in the levels of rejection in
direct relation to the number of relevant attributes shared
between host and parasite eggs.Molothrus bonariensis). Immaculate eggs are the only
parasite eggs rejected by this host, as it accepts all polymorphic,
spotted eggs laid by cowbirds. Using a withinbreeding
pair experimental design, we tested for the salience
of spotting, UV reflectance, and brightness in eliciting
rejection. We found that the presence of spotting
significantly decreased the probability of rejection while
increments in brightness significantly increased rejection
frequencies. The cognitive rules underlying mockingbird
rejection behavior can be explained by a decision-making
model which predicts changes in the levels of rejection in
direct relation to the number of relevant attributes shared
between host and parasite eggs.