Extra-pair parentage and personality in a cooperatively breeding bird

Area of Science:

• Behavioral Ecology
• Evolutionary Biology
• Ornithology

Background:

• Variation in extra-pair parentage (EPP) is common, but its causes are not fully understood.
• Personality traits, like exploratory behavior, are hypothesized to influence reproductive strategies and EPP.
• Seychelles warblers exhibit cooperative breeding and are a model system for studying social and mating behaviors.

Purpose of the Study:

• To investigate the association between exploratory behavior and reproductive outcomes in Seychelles warblers.
• To determine if exploratory behavior influences the number of offspring and the occurrence of extra-pair offspring.
• To test if males' exploratory behavior affects their mate's propensity for extra-pair parentage.

Main Methods:

• Observational study of a natural population of Seychelles warblers on Cousin Island.
• Quantification of individual exploratory behavior (propensity to explore novel environments/objects).
• Analysis of reproductive success, including total offspring and extra-pair offspring, using genetic methods.

Main Results:

• Exploratory behavior in both males and females was not significantly correlated with the total number of offspring produced.
• No significant association was found between an individual's exploratory behavior and the number of extra-pair offspring.
• Females in behaviorally dissimilar pairs showed a small, but significant, tendency towards extra-pair fertilizations.

Conclusions:

• Exploratory behavior does not appear to be a major driver of variation in reproductive success or extra-pair paternity in this population.
• The observed link between behavioral disassortativity and female extra-pair fertilization was of small effect size, suggesting limited biological relevance.
• Individual differences in exploratory behavior may not have significant long-term fitness consequences in Seychelles warblers.