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08:41
Quantifying Abdominal Pigmentation in Drosophila melanogaster
Published on: June 1, 2017
Covariation between eumelanic pigmentation and body mass only under specific conditions
1Department of Ecology and Evolution, Biophore, University of Lausanne, 1024 Lausanne, Switzerland. Alexandre.Roulin@unil.ch
Die Naturwissenschaften
|January 6, 2009
Summary
Covariation between barn owl plumage ornaments and body mass depends on feeding times. This suggests melanin-based ornaments signal energy reserves, detectable only under specific conditions.
Area of Science:
- Ecology
- Evolutionary Biology
- Animal Behavior
Background:
- Covariation between ornaments and other traits informs ornament signaling function.
- Environmental conditions can alter trait covariation due to condition-dependence.
Purpose of the Study:
- Investigate how food supply, reproductive cycle, and time of day affect covariation between body mass and melanin-based plumage ornaments in barn owls (Tyto alba).
- Test the hypothesis that eumelanin-based ornaments signal energy balance.
Main Methods:
- Analyzed 1,848 body mass measurements from 336 breeding female barn owls.
- Examined covariation between body mass and black plumage spot size.
- Assessed variations across feeding conditions (morning vs. afternoon) and reproductive stages.
Main Results:
- Heavier females with larger black spots were observed in the afternoon, not the morning.
- Covariation between body mass and black spot size was condition-dependent, linked to feeding times.
Conclusions:
- Melanin-based ornaments may signal an individual's ability to maintain energy balance.
- The detectability of trait covariation is context-specific, explaining varied findings across species.
- Future research should test the environment-specific fitness benefits of ornamentation in other species.
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