Contemporary divergence of island bird plumage

Julian D. Avery, Phillip Cassey, Julie L. Lockwood

Research output: Contribution to journalArticlepeer-review

4 Citations (SciVal)


Although the diversity in avian plumage coloration is striking, there is little known about the rate with which colour diverges. Eastern bluebirds Sialia sialis bermudensis on the island of Bermuda are considered endemic based upon differences in coloration from the mainland, but recent molecular evidence suggests they established on the island only 400 yr ago. We explored sexual dichromatism and colour divergence in this isolated population, thus providing one of the few quantitative accounts of contemporary plumage change. Contrary to expectations that sexual dichromatism would decrease in this sedentary island population, we found that males and females have increased plumage ornamentation in a coordinated fashion that acts to preserve sexual dichromatism, while plumage colour is also altered to become brighter and bluer. These differences were in place at least 100 yr ago based upon a separate analysis of museum specimens. Our results provide insight into the divergence of plumage colour in an incipient species, and we show the remarkable extent to which plumage colour can change over contemporary time frames.

Original languageEnglish (US)
Pages (from-to)291-295
Number of pages5
JournalJournal of Avian Biology
Issue number3
StatePublished - May 2014

All Science Journal Classification (ASJC) codes

  • Ecology, Evolution, Behavior and Systematics
  • Animal Science and Zoology


Dive into the research topics of 'Contemporary divergence of island bird plumage'. Together they form a unique fingerprint.

Cite this