Related Experiment Video
Updated: Jun 8, 2026
08:14
Who is Who? Non-invasive Methods to Individually Sex and Mark Altricial Chicks
Published on: May 24, 2014
Colourful parrot feathers resist bacterial degradation
Edward H Burtt1, Max R Schroeder, Lauren A Smith
1Department of Zoology, Ohio Wesleyan University, Delaware, OH 43015, USA. ehburtt@owu.edu
Biology Letters
|October 8, 2010
Summary
Parrot feather colors, like red psittacofulvins, help protect feathers from bacterial degradation. This suggests feather coloration in parrots may have evolved for durability, not just appearance.
Area of Science:
- Avian Biology
- Biochemistry
- Materials Science
Background:
- Bird feather coloration often involves pigments like melanin and psittacofulvins.
- Feather structural integrity is crucial for avian health and survival.
- Pigments may offer protection against environmental stressors, including microbial degradation.
Purpose of the Study:
- To investigate the role of psittacofulvins and other feather colors in resistance to bacterial degradation.
- To compare the degradation rates of differently colored parrot feathers exposed to Bacillus licheniformis.
Main Methods:
- Exposure of various parrot feather types (red, blue, green, white, black) to feather-degrading bacteria Bacillus licheniformis.
- Quantification of feather degradation rates based on color and pigment composition.
Main Results:
- Feathers containing red psittacofulvins showed similar degradation rates to melanin-based feathers.
- White feathers, lacking pigments, degraded faster than pigmented feathers.
- Blue and green feathers exhibited degradation rates comparable to red and black feathers.
Conclusions:
- Parrot feather colors, particularly psittacofulvins, contribute to resistance against bacterial degradation.
- Feather coloration in parrots may have evolved with a dual function: communication and enhanced plumage durability.
- These findings offer insights into the evolutionary pressures shaping avian feather structures and coloration.
Related Concept Videos
01:20Mate Choice
Mate choice—the decision about whom to mate with—is a type of natural selection, since animals must reproduce to pass down their genes. Mate choice is also called intersexual selection because the behavior occurs between the sexes.
01:21Frequency-dependent Selection
When the fitness of a trait is influenced by how common it is (i.e., its frequency) relative to different traits within a population, this is referred to as frequency-dependent selection. Frequency-dependent selection may occur between species or within a single species. This type of selection can either be positive—with more common phenotypes having higher fitness—or negative, with rarer phenotypes conferring increased fitness.Positive Frequency-Dependent SelectionIn positive...
00:49Complementation Tests
A complementation test is a simple cross to identify whether the two mutations are located on the same gene or different genes. It was first performed by Edward Lewis in the 1940s while working on fruit flies. He developed the test to identify the location and arrangement of different mutations on chromosomes.
Organisms heterozygous for different mutations are crossed pairwise in all combinations. If present on different genes, the mutations can complement each other by providing the missing...
Organisms heterozygous for different mutations are crossed pairwise in all combinations. If present on different genes, the mutations can complement each other by providing the missing...
02:07Conservation of Declining Populations
Conservation of declining population focuses on ways of detecting, diagnosing, and halting a population decline. The approach uses methods to prevent populations from going extinct.
01:38Limits to Natural Selection
Organisms that are well-adapted to their environment are more likely to survive and reproduce. However, natural selection does not lead to perfectly adapted organisms. Several factors constrain natural selection.For one, natural selection can only act upon existing genetic variation. Hypothetically, redtusks may enhance elephant survival by deterring ivory-seeking poachers. However, if there are no gene variants—or alleles—for redtusks, natural selection cannot increase the prevalence of...