Diferenças intersexuais crípticas no lagarto Cnemidophorus ocellifer (Spix, 1825)

Abstract

Colorful ornaments are commonly thought to be results of sexual selection, expressed by the sex experiencing intense selective pressure. However, empirical evidence suggests that conspicuous coloration can be present in both sexes. Evolutionary theory of mutual ornaments suggests female coloration is either the result of genetic correlation (=intense coloration has evolutionary advantages only for males) or mutual selection (=intense coloration has evolutionary advantages in both sexes). My aim was to investigate the possible selective forces acting on females ornaments in a mutually ornamented lizard species. I analyzed coloration of eyespots and outer ventral scales (OVS) found in both sexes of Cnemidophorus ocellifer. I investigated differences between sexes and correlations between color and morphological quality traits. Both ornaments investigated had strong reflectance in ultraviolet (UV) and medium wavelengths (green). Males had significantly more intense UV and green coloration than females, and ocelli coloration was associated with body size only in females. These results are in line with predictions of genetic correlation theory. Additionally, larger individuals of both sexes showed more intense OVS coloration, showing that selective forces acting on ocelli and OVS coloration might be of different magnitude. My results support the hypothesis that female coloration is produced by genetic correlation, resulting in multiple colorful ornaments. However, selection pressure can be different on individual color patches suggesting a complex system of interacting selective forces.