Animal coloration can be the result of many interconnected elements, including the production of colour-producing molecules de novo, as well as the acquisition of pigments from the diet. When acquired through the diet, carotenoids (a common class of pigments) can influence yellow, orange, and red coloration and enhanced levels of carotenoids can result in brighter coloration and/or changes in hue or saturation. We tested the hypothesis that dietary carotenoid supplementation changes the striking black and yellow coloration of the southern corroboree frog (Pseudophryne corroboree, Amphibia: Anura). Our dietary treatment showed no measurable difference in colour or brightness for black patches in frogs. However, the reflectance of yellow patches of frogs raised on a diet rich in carotenoids was more saturated (higher chroma) and long-wave shifted in hue (more orange) compared to that of frogs raised without carotenoids. Interestingly, frogs with carotenoid-poor diets still developed their characteristic yellow and black coloration, suggesting that their yellow colour patches are a product of pteridines manufactured de novo.
Bibliographical noteFunding Information:
We thank the anonymous reviewers for useful feedback on the manuscript, as well as John Endler, Martin Stevens, Devi Stuart-Fox, Thomas White, Jan Hemmi, and Danielle Klomp for advice on colour and pattern analysis. We also thank the staff in the Herpetology Department of Melbourne Zoo for providing the Southern Corroboree Frog eggs, and Taronga Zoo's Herpetofauna Division (Adam Skidmore, Michael McFadden, and Dr Peter Harlow) for advice on captive husbandry requirements, as well as their assistance with the construction of the automated tadpole-rearing system.
© 2016 The Linnean Society of London
- morphological colour change
- ontogenetic colour change