Different Colors on Different Soils

Corl, A. Ke bi, C Lke et al. The genetic basis of adaptation following plastic changes in coloration in a novel environment. Current Biology 28(18):2970-2977.

Variation in color of side-blotched lizards. (Left) A dark side-blotched lizard from Joshua Tree National Park, California; Photo: Greg Schechter, CCbySA2.0; (Center) A reddish side-blotched lizard from Capitol Reef National Park, Utah, Photo: browbrooks, CCbySA2.0; (Right) A pale side-blotched lizard from San Antonio, New Mexico, Photo: Greg Schechter, CCbySA2.0.

Summary. Side-blotched lizards (Uta stansburiana) living on a lava flow in eastern California have increased pigmentation that matches well with the black lava. Genetic studies found that two genes, PREP and PRKARIA showed strong genetic differences between the lava population and the lizards in the surrounding desert. These two genes are known to be regulators of melanin production, and are linked to the darker pigmentation of the lava-dwelling lizards. Variability in coloration promotes the ability of the lizards to adapt to environments with different background colors. Natural selection then favored individuals with darker pigmentation so that the population now blends well with the black lava on which they live.

Comment. Animals commonly vary in color in different habitats. This is an interesting example because the study identifies the probable genetic basis of the color change. This kind of variation appears to be part of the design given to animals to enable them to disperse and adapt throughout the world after the Flood.