Document Type
Article
Publication Date
5-2014
Published In
Journal of Evolutionary Biology
Volume
27
Issue
5
Pages
982-991
Recommended Citation
Freeman-Gallant, Corey R.; Schneider, Rebecca L.; Taff, Conor C.; and Dunn, Peter O., "Contrasting Patterns of Selection on the Size and Coloration of a Female Plumage Ornament in Common Yellowthroats" (2014). Biology. 8.
https://creativematter.skidmore.edu/bio_fac_schol/8
Abstract
Females often possess ornaments that appear smaller and duller than homologous traits in males. These ornaments may arise as nonfunctional by-products of sexual selection in males and cause negative viability or fecundity selection in females in proportion to the cost of their production and maintenance. Alternatively, female ornaments may function as signals of quality that are maintained by sexual or social selection. In a 4-year study of 83 female common yellowthroats (Geothlypis trichas) and their 222 young, we found strong viability and fecundity selection on the yellow bib, a carotenoid-based plumage ornament that is a target of sexual selection in males. Females with larger bibs were older, larger and more fecund than females with smaller bibs. However, bib size positively covaried with bib total brightness and carotenoid chroma, aspects of bib coloration that were under negative viability and fecundity selection. Females with more colourful bibs laid fewer eggs in their first clutch, were more likely to suffer total brood loss due to predation and were less likely to return to the study area. Selection against bib coloration limits the value of bib size as a quality indicator in females and may constrain the elaboration of bib attributes in males.
Keywords
condition dependence, epigamic signalling, good genes, sexual dimorphism