Smaller, smaller, smaller

The south of Puerto Rico has a stable hybrid zone between two species of dwarf geckos. Hybrid populations were first studied 36 years ago using Electrophoretic data for 23 loci and were re-visited last year. Although genetic data validates the presence of a geographically stable hybrid zone, the morphological changes attributed to hybridization have not been described in detail. Here we study variation of color pattern and body proportions between parental species and the putative hybrids to characterize changes due to hybridization. For this project we Xrayed 91 specimens, and photographed specimens of each group. Using the X-rays, we measure 15 skeletal elements, and combine the data with external features of their coloration pattern. We plan to analyze this data to identify traits accounting for variability and perform further analysis that might help better understand phenotypic changes attributed to hybridization. Preliminary observations indicate hybrids are larger than parental populations.