DISSERTATION RESEARCH: A PHYLOGENOMIC APPROACH FOR UNDERSTANDING THE SYSTEMATICS AND PHENOTYPIC DIVERSIFICATION OF AUSTRALASIAN GECKO LIZARDS

人类对产生当前物种多样性模式的进化过程知之甚少。更好地理解这些过程的最好群体是那些在物种数量和形态上都辐射得很快的群体。这项研究将使用一组仅限于澳大利亚、新西兰、新几内亚和太平洋上相关岛屿（澳大拉西亚）的壁虎蜥蜴，这些壁虎的体型表现出多样性，从四肢齐全的物种（非常熟练的攀爬者）到完全没有四肢的陆地物种（澳大拉西亚）。研究人员将重建种群内的进化关系，然后研究该地区地理分布的变化如何影响物种形成的速度和形态变化的速度。一名研究生和几名本科生将接受实验室技术培训。研究结果将纳入K-12课堂活动，并将广泛传播给公众。本项目旨在利用超保守元件（UCEs）系统基因组学方法提高对澳大利亚壁虎系统发育关系的认识。该分支中估计有200个物种，将对5000个已发表的UCE位点进行采样，以为该群体提供一个得到充分支持的系统发育。在脊椎动物博物馆开发的管道将用于DeNovo组装。将使用连接和聚结的物种树（ASTRAL， ASTRID， SNAPP和MP-est）。这组壁虎（150个物种，1100个标本）的大型生态形态学数据集已经通过照片和24次线性测量来测试有关表型进化的问题。由此产生的物种水平的系统发育将被用来推断整个树的净多样化率的异质性，以及使用系统发育比较方法推断某些生态相关性状多样化的异质性。这些相同的生态形态特征也将被用来测试趋同进化在这个分支中不相关的壁虎中的流行程度。

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.