SYNTOPIC OCCURRENCE OF MULTIPLE DEWLAP COLOR MORPHS IN MALE TREE LIZARDS, UROSAURUS-ORNATUS

We describe a color polymorphism in male tree lizards, Urosaurus ornatus, that may be one of the most complex social badge polymorphisms known. Male tree lizards in central Arizona possess dewlaps that are solid blue, solid yellow or solid orange, or bicolored consisting of a yellow or orange background with a blue central spot that varies continuously in size from a few scales to 55% of the area of the unextended dewlap. The occurrence of this polymorphism varies geographically and microgeographically, from populations that are monomorphic, to those that are dominated by two dewlap morphs, to those where of the different morph types both within and between years suggests no evidence of differential fitness between the morphs. Comparisons between habitats suggest that morph complexity was highest in the better quality habitat of the two sites we compared.