Zoology Faculty Work
Title
Gloger's Rule, Feather-Degrading Bacteria, and Color Variation Among Song Sparrows
Document Type
Article
Publication Date
2004
Publication Title
The Condor: Ornithological Applications
Volume Number
106
Issue Number
3
DOI
10.1650/7383
Abstract
Feathers tend to be darkly colored in habitats where relative humidity is high and pale where it is low. We suggest that this correlation, known as Gloger's rule, results, in part, from selection for dark feathers that are more resistant than light feathers to bacterial degradation, which is a severe problem in humid habitats where bacteria thrive and a lesser problem in arid habitats. In May and June 2000–2002 we sampled feather-degrading bacteria (Bacillus licheniformis) from the plumage of Song Sparrows (Melospiza melodia) in southeastern Arizona and northwestern Washington. Under standardized laboratory conditions, feather-degrading bacteria from the plumage of sparrows in the humid Northwest degraded feathers more rapidly and more completely than feather-degrading bacteria from sparrows of the arid Southwest. The differences in feather-degrading bacteria and in relative humidity produce a difference in the intensity of selection, which in turn produces the difference in color described in Gloger's rule.
ISSN
0010-5422
First Page
681
Last Page
686
Recommended Citation
Burtt, Edward H. Jr. and Ichida, Jann M., "Gloger's Rule, Feather-Degrading Bacteria, and Color Variation Among Song Sparrows" (2004). Zoology Faculty Work. 61.
https://digitalcommons.owu.edu/zool_pubs/61
Link Out URL
https://doi.org/10.1650/7383