The evolutionary processes that have produced current patterns of species diversity are poorly understood. The best groups to better understand these processes are those that have radiated quickly both in terms of species number and morphological form. This study will use a group of gecko lizards restricted to Australia, New Zealand, New Guinea and associated islands in the Pacific Ocean (Australasia) that exhibit a diversity of body-forms, ranging from fully limbed species that are very adept climbers to terrestrial forms completely lacking limbs. Researchers will reconstruct evolutionary relationships within the group and then investigate how changes in geographical distribution within the area have affected the rate of species formation and the rate of change in morphological form. One graduate student and several undergraduate students will be trained in laboratory techniques. Findings from the research will be incorporated into a K-12 classroom activity and will also be broadly disseminated to the public.
This project aims to improve understanding of the phylogenetic relationships among Australasian geckos by using an ultraconserved elements (UCEs) phylogenomics approach. All of the estimated 200 species in the clade will be sampled for 5,000 published UCE loci to produce a well-supported phylogeny for the group. Pipelines developed in the Museum of Vertebrate Zoology will be used for DeNovo assembly. Concatenated and coalescent species trees (ASTRAL, ASTRID, SNAPP, and MP-est) will be used. A large ecomorphology dataset for this group of geckos (150 species, 1,100 specimens) has been assembled using photographs and 24 linear measurements to test questions regarding phenotypic evolution. The resulting species-level phylogeny will then be used to infer heterogeneity in net diversification rate across the tree and heterogeneity in the diversification of certain ecologically relevant characters using phylogenetic comparative methods. These same ecomorphological characters will also be used to test the prevalence of convergent evolution in unrelated geckos in this clade.
Jimmy McGuire. DISSERTATION RESEARCH: A PHYLOGENOMIC APPROACH FOR UNDERSTANDING THE SYSTEMATICS AND PHENOTYPIC DIVERSIFICATION OF AUSTRALASIAN GECKO LIZARDS. 2016-01-01.