The second-to-fourth digit ratio (2D/4D) is a well-studied sexual dimorphism that likely arises as a result of prenatal androgenic effects on homeobox gene expression. This dimorphism has been found to exhibit interesting phylogenetic patterns in which females have larger ratios than males among most mammalian species and males have larger ratios than females in most avian and reptilian species. This study measured the second and fourth digits of all limbs from 25 adult males and 25 adult females of Gonatodes albogularis. There were no significant differences between the (2D/4D) for gender as sexual dimorphism of the species. These results indicate that this species of tree lizard deviates from the ratio shown by diapsid species. Possible associated environmental factors are discussed.
Tree skink; Limbs; Digit ratio; Sexual dimorphism
