Geographic Differences of Growth Rate of Sceloporus Lizards (Sauria: Iguanidae)

Abstract

Laboratory produced hatchlings of S. graciosus graciosus, S. undulatus consobrinus, S. u. garmani and S. u. undulatus that were raised under identical social, thermal-gradient and feeding environments grew at significantly distinct, population-specific rates. Growth rates expressed in the laboratory closely approximated those measured in the field for some populations, but were higher in the laboratory for others. Juvenile growth rate differences measured in the field seem due in part to genetic differences and in part to differences in the quality of the natural growing environment.