Background color impacts growth, survivorship, and color development in an African cichlid

Many animals can change color to match their surroundings as they attempt to increase camouflage to avoid predation. Examples include seasonal coat color change in artic foxes or rapid color change in cuttlefish. While phenotypic adjustment to the environment may be advantageous in heterogeneous environments, phenotypic plasticity can be costly too when plastic changes are accompanied by changes in other traits that are not necessarily beneficial. Describing these costs is important for understanding the adaptive significance of phenotypic plasticity. In the African cichlid Astatotilapia burtoni males are yellow or blue and color is plastic. Previous studies indicate these two color phenoyptes are expressed in light or dark color environments in nature, respectively. We tested how background color impacts growth and survivorship by housing juveniles in groups and adult males in isolation in tanks with yellow or blue backgrounds. We confirmed that A. burtoni matched the color of their background. We then found that juveniles grew larger in yellow tanks but had higher mortality than those that were housed in blue tanks. There were no background color effects in isolated adult males. We also plan to evaluate oxidative stress markers to examine how background color matching influences physiological stress. Our study shows that background color matching is associated with potential costs which may influence the adaptive significance of plasticity in body coloration in changing environments.