Meeting Abstract
Tetrapod digits are often characterized by sexually dimorphic digit proportions. For example, in humans and mice, the second digit is generally shorter than the fourth digit, and, as such, the second to fourth digit length ratio (2D:4D) is generally <1. In females, by contrast, the second and fourth digits are of similar length, giving them a 2D:4D ratio >1. This trend has been attributed to differences in embryonic exposure to androgen and estrogen between males and females. Sexual dimorphism in digit ratios has been described across many mammalian species; however, there is limited information about the conservation of this trend across all tetrapods. A handful of studies have described sexual dimorphism in digit ratios in some species of frogs, lizards, and birds. We examined digit development in the iguanid lizard Anolis sagrei to determine whether sexually dimorphic digit proportions is conserved between mammals and squamates.
