Pathways linking female personality with reproductive success are trait- and year-specific. (10th November 2020)

• Record Type: Journal Article
• Authors: Thys, Bert; Eens, Marcel; Pinxten, Rianne; Iserbyt, Arne
• Editors: Naguib, Marc
• Is Part Of: Behavioral ecology. Volume 32:Number 1(2021)
• Page Start: 114
• Page End: 123
• Publication Date: 2020-11-10
• Subjects: animal personality -- female–female aggression -- hissing behavior -- parental care -- path analysis -- Parus major; Animal behavior -- Periodicals; Behavior evolution -- Periodicals; Ecology -- Periodicals; Psychology, Comparative -- Periodicals; 591.5
• DOI: 10.1093/beheco/araa110
• Languages: English
• ISSNs: 1045-2249

Abstract

Abstract: Personality (i.e., among-individual variation in average behavior) often covaries with fitness, but how such personality–fitness relationships come about is poorly understood. Here, we explore potential mechanisms by which two female personality traits (female–female aggression and female nest defense as manifested by hissing behavior) were linked with annual reproductive success in a population of great tits ( Parus major ), a socially monogamous species with biparental care. We hypothesized that personality-related differences in reproductive success result from variation in reproductive decision (lay date, brood size) and/or parental provisioning rates. Relative support for these mechanisms was evaluated using path analysis on data collected in two successive years. We reveal that larger broods were provisioned at a higher rate by both parents and that female, but not male, provisioning rate was involved in the trade-off between offspring number (brood size) and fledgling mass. Among-individual variation in female aggression, via its association with female provisioning rate, was negatively linked to fledgling mass (i.e., indirect effect), yet only in one of the study years. Male provisioning rate did not influence these relationships. In contrast, among-individual variation in hissing behavior was directly and negatively linked with fledgling mass in both years, via an underlying mechanism that remains to be identified (i.e., direct effect). Together, our findings emphasize that personality–fitness relationships may come about via different mechanisms across personality traits and/or years, thereby illustrating additional complexity in how selection might act on and maintain among-individual variation in behavioral phenotypes in the wild. Abstract : Mechanisms linking female personality with reproductive success varied between traits and years in a songbird species. Only in 1 year, female–female aggression was negatively related with fledgling mass via its association with female provisioning rate. By contrast, female nest defense was negatively associated with fledgling mass in both years via a currently unknown mechanism. It is important to consider the dynamic nature of personality–fitness relationships in future studies.