Synopsis For decades, scientists have noted connections between individual condition and carotenoid-based coloration in terrestrial and aquatic animals. Organisms that produce more vibrant carotenoid-based coloration tend to have better physiological performance and behavioral displays compared with less colorful members of the same species. Traditional explanations for this association between ornamental coloration and performance invoked the need for color displays to be costly, but evidence for such hypothesized costs is equivocal. An alternative explanation for the condition-dependence of carotenoid-based coloration, the Shared-Pathway Hypothesis (SPH), was developed in response. This hypothesis proposes that red ketocarotenoid-based coloration is tied to core cellular processes involving a shared pathway with mitochondrial energy metabolism, making the concentration of carotenoids an index of mitochondrial function. Since the presentation of this hypothesis, empirical tests of the mechanisms proposed therein have been conducted in several species. In this manuscript, we review the SPH and the growing number of studies that have investigated a connection between carotenoid-based coloration and mitochondrial function. We also discuss future strategies for assessing the SPH to more effectively disentangle evidence that may simultaneously support evidence of carotenoid-resource tradeoffs.
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Intra‐population variation in male nuptial coloration and diet across anthropogenically altered visual microhabitats in an African cichlid
Human activities are altering natural ecosystems, leading to widespread environmental change that can vary across spatiotemporal scales, thus creating dynamic, novel conditions at both large and small scales. In highly disturbed aquatic systems, elevated turbidity is one common stressor that alters the sensory environment of fishes and can disrupt communication, including mate choice, driving population‐level shifts in visual communication traits such as nuptial coloration. At a smaller, within‐population scale, we can expect similar adaptive divergence to a heterogeneous visual landscape. Using the cichlid fish,
- Award ID(s):
- 1656542
- NSF-PAR ID:
- 10370241
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Journal of Zoology
- Volume:
- 317
- Issue:
- 4
- ISSN:
- 0952-8369
- Page Range / eLocation ID:
- p. 294-304
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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