ATOL: Collaborative Research: Archosaur Phylogeny - A Total Evidence Approach at Fine Taxonomic Levels

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Collaboartive Research: Archosaur phylogeny-a total evidence approach at fine taxonomic levelLiving birds form an extensive, undoubtedly monophyletic assemblage of vertebrates. Yet even after over 150 years of intense study the interrelationships of the orders, families, and genera of extant birds are still poorly understood. Recently it has beenconclusively demonstrated that birds are nested within theropod dinosaurs. Fossils of some of these groups have been found that display a number of features that have previously been thought of as avian (e.g. feathers, brooding behavior, furculae). We propose to examine the relationships of theropod dinosaurs (including birds) using a total evidence approach at very fine levels. In the morphological analysis we will develop a matrix of scoreable characters across the entire diversity of non-avian theropods andat fine taxonomic levels within birds (I.e. near the generic level). Molecular analyses will use high-throughput sequencing techniques to produce molecular sequences from birds and outgroup taxa. Nuclear genes will be used predominantly to complement prior mitochondrial sequencing; the RAG-1 exon will be sequenced for most genera of extant birds, and additional genes such as RAG-2, MC3R, and cMOS will be sequenced for exemplars to establish deeper level relationships. Analysis of these data will result in a fine-grained phylogenetic hypothesis of living and fossil birds and their close theropod relatives. Such a phylogeny will have obvious importance for the study of a broad range of evolutionary questions within theropods. A major focus of this grant is the development of a 'supermatrix'. We envision this matrix to be a virtual archive for all the character information that we generate during this study. Several different kinds of data will be stored here. Digital images of specimens will allow character conditions to be examined within the context of the matrix. Molecular information will be available as well. Capabilities for the development and export of character matrices into formats conventionally used for phylogenetic analysis will also be available. As this information is published it will be made available over the www.