Animal species display tremendous diversity in body size and shape, yet relatively little is known regarding the genetic mechanisms responsible for these differences. The objective of this project is to examine this question by determining whether species that exhibit similar limb lengths acquire these comparable limb morphologies through related developmental mechanisms. Anolis lizards are ideal for these studies since they display remarkable differences in limb length between species. During the course of this project the pattern of limb growth and gene expression will be compared between multiple different long-limbed and short-limbed Anolis species. In addition, Anolis species with naturally occurring differences in DNA sequences that control hindlimb formation will be investigated to determine whether these sequence differences can directly alter the function of limb genes. These developmental and molecular analyses will reveal whether different species with similar body forms achieve a similar final appearance through the same or different means. The proposed studies will also generate broader impacts through the creation of new teaching and training opportunities for undergraduate, graduate, and postdoctoral scholars, as well by providing resources that will advance Anolis lizards as a new model system for developmental studies. Finally, the project will integrate research and education through a research module that has been developed for an advanced undergraduate molecular genetics laboratory course.