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

人们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佳群体是那些在物种数量和形态形式方面都迅速辐射的群体。这项研究将使用一群生活在澳大利亚、新西兰、新西兰和太平洋(澳大拉西亚)相关岛屿上的壁虎蜥蜴，它们的身体形态多种多样，从非常擅长攀爬的完全四肢的物种到完全没有四肢的陆生物种。研究人员将重建种群内部的进化关系，然后调查该区域内地理分布的变化如何影响物种形成的速度和形态形式的变化速度。一名研究生和几名本科生将接受实验室技术培训。这项研究的结果将纳入一项K-12课堂活动，并将广泛传播给公众。该项目旨在通过使用超保存元素(UCES)系统发生学方法来提高对澳大利亚壁虎之间系统发育关系的理解。该分支中估计的所有200个物种将为5000个已发表的UCE基因座进行采样，以产生一个得到充分支持的该群体的系统发育图。在脊椎动物博物馆开发的管道将用于DeNovo的组装。将使用串联和合并物种树(Astral、Astrid、Snapp和MP-Est)。使用照片和24个线性测量收集了这组壁虎(150个物种，1,100个标本)的大型生态地貌数据集，以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净多样化比率的异质性和利用系统发育比较方法在某些生态相关特征的多样化方面的异质性。这些相同的生态地貌特征也将被用来测试该支系中无关壁虎的收敛进化的盛行程度。

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.