Coloration and Lability of Color in the Brown Anole, Anolis sagrei

Abstract

The nonnative Brown anole (Anolis sagrei) is the most abundant lizard in peninsular Florida and is a common inhabitant of urban and suburban environments where it competes with native Green anoles (A. carolinensis).  Brown anoles are largely diurnal and considered to be a "ground-trunk" ecomorph, typically basking or perching on shrubs and numerous objects near the ground.  There is considerable intraspecific variation and plasticity of body colors, but changes of color to match backgrounds in context of crypsis are not well understood.  Here we describe the variety of colors exhibited in Brown anoles, and we report observations of color change in lizards that were observed continuously or intermittently for variable periods of time.  In contexts generally associated with basking, lizards either lightened or darkened to colors that enhanced camouflage.  Moreover, lizards that habitually perched on favored objects were noted to display colors and patterns that were cryptic on respective backgrounds.  We suggest that crypsis is an important function of coloration in Brown anoles, and plasticity of color change as well as postural behaviors enhance camouflage in this species.