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Related Concept Videos

Mate Choice01:20

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Related Experiment Video

Updated: Jun 25, 2026

Who is Who? Non-invasive Methods to Individually Sex and Mark Altricial Chicks
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Published on: May 24, 2014

Ornamental plumage does not signal male quality in red-billed queleas.

J Dale1

  • 1Department of Neurobiology and Behavior, Cornell University, Ithaca, NY 14853-2702, USA. jd11@cornell.edu

Proceedings. Biological Sciences
|June 21, 2001
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Summary

Red-billed quelea plumage coloration is not a reliable indicator of male quality. Instead, this sexually selected trait may signal individual identity in dense breeding colonies.

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Area of Science:

  • Evolutionary biology
  • Animal behavior
  • Ornithology

Background:

  • Sexually selected ornaments often act as condition-dependent signals of individual quality.
  • Costly ornamentation implies that only high-quality individuals can afford elaborate signals.
  • Red-billed quelea (Quelea quelea) plumage is a potential indicator due to its variability, conspicuousness, and carotenoid basis.

Purpose of the Study:

  • To investigate whether red-billed quelea plumage ornamentation functions as a condition-dependent signal of quality.
  • To determine if plumage coloration is a reliable indicator of physical condition, age, or reproductive success.

Main Methods:

  • Analysis of plumage color variation in relation to physical condition and age.
  • Assessment of the genetic basis and environmental responsiveness of plumage coloration.
  • Examination of plumage character distributions and interdependencies.
  • Correlation of plumage color with reproductive success.

Main Results:

  • Quelea plumage color showed no correlation with physical condition or age.
  • Plumage coloration is a genetically determined trait, unresponsive to environmental variation.
  • Plumage characters exhibited bimodal distributions and independent variation.
  • Plumage color was not correlated with reproductive success.

Conclusions:

  • Red-billed quelea plumage does not function as a condition-dependent indicator of quality.
  • This study provides the first evidence of non-condition dependence in colorful, sexually dimorphic breeding ornamentation.
  • Plumage variation may serve as a sexually selected signal of individual identity in dense colonies.