Behavioral Ecology and Sociobiology

, Volume 61, Issue 9, pp 1391–1399

Diet quality affects an attractive white plumage pattern in dark-eyed juncos (Junco hyemalis)

  • Joel W. McGlothlin
  • Deborah L. Duffy
  • Jessica L. Henry-Freeman
  • Ellen D. Ketterson
Original Paper

DOI: 10.1007/s00265-007-0370-x

Cite this article as:
McGlothlin, J.W., Duffy, D.L., Henry-Freeman, J.L. et al. Behav Ecol Sociobiol (2007) 61: 1391. doi:10.1007/s00265-007-0370-x

Abstract

Sexually selected traits that act as signals of quality often display some degree of condition dependence. In birds, condition dependence of ornamental plumage is often mediated by production costs related to acquisition or allocation of dietary resources. White plumage ornaments, however, have often been assumed to be inexpensive because their production requires neither pigment nor specialized feather structure. In male dark-eyed juncos (Junco hyemalis), the size of a white patch on the tail contributes to attractiveness and mating success. Using captive males, we examined the effects of diet quality on the size and brightness of the tail-white patch. After removing four tail feathers to induce replacement, we maintained subjects on a subsistence (low-protein) or enriched (high-protein) diet while induced feathers grew. Birds that received an enriched diet grew their feathers more quickly and grew larger, brighter white patches. Feather growth rate was positively correlated with the increase in the size of the tail-white patch, a relationship that was stronger in the subsistence diet group. However, within diet treatments, faster-grown feathers were slightly duller. Taken together, these results suggest that variation in diet quality may lead to condition-dependent expression of tail white and that condition dependence may be stronger in more stressful environments. We suggest a mechanism by which increased feather growth rate may lead to an increase in the size of the tail-white patch and discuss potential trade-offs between signal size and brightness.

Keywords

Honest signalsCondition dependenceSexual selectionPlumage developmentJunco hyemalis

Copyright information

© Springer-Verlag 2007

Authors and Affiliations

  • Joel W. McGlothlin
    • 1
    • 2
  • Deborah L. Duffy
    • 1
    • 2
    • 3
  • Jessica L. Henry-Freeman
    • 1
    • 2
  • Ellen D. Ketterson
    • 1
    • 2
  1. 1.Department of BiologyIndiana UniversityBloomingtonUSA
  2. 2.Center for the Integrative Study of Animal BehaviorIndiana UniversityBloomingtonUSA
  3. 3.Department of Clinical Studies, Center for the Interaction of Animals and Society, School of Veterinary MedicineUniversity of PennsylvaniaPhiladelphiaUSA