Assembing the Tree of Life: An Integrative Approach to Investigating Cnidarian Phylogeny

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The phylum Cnidaria is one of the earliest evolving animal groups and includes prominent members of the marine fauna such as corals, sea anemones and jellyfish. Because cnidarians diverged from the rest of the animals prior to the evolution of organs, their overall anatomy is quite simple. Despite this however, cnidarians have attained incredible diversity, comprising over 11,000 species, many of which display elaborate structures and complex life histories. The lack of organs and other anatomical landmarks has made it difficult for scientists to discern their evolutionary relationships. Recent technological and theoretical advances in the sequencing and analysis of DNA provide the opportunity to use the information encoded within an organism's genetic code to elucidate evolutionary relationships. The primary aim of this proposal is to obtain DNA sequence data from 1,800 cnidarian species: this will generate approximately 23 million base pairs of cnidarian DNA sequence, and the specimens from which the sequences are obtained will be retained in natural history museum collections. The information encoded in the DNA will be used to reconstruct cnidarian phylogenies (evolutionary trees), using computer algorithms and supercomputing facilities. Some of the questions this proposal will address are: Was the ancestor to all of cnidarians solitary or colonial? Are jellyfish or hydras more closely related to the corals? How and when did coral skeletons evolve? What are the evolutionary transitions between a simple hydra polyp and a complex Portuguese Man-of-War colony? Reconstructing a cnidarian evolutionary tree is important for our understanding of the patterns and processes that accompanied the early diversification of animal life. Formal and informal education will result from this research. Undergraduate, graduate, and postdoctoral scholars, including those belonging to groups under-represented in the sciences, will be trained. A symposium on cnidarian evolutionary relationships will be organized by the investigators at a national scientific meeting. A Cnidaria Tree of Life database will be developed to include outreach and learning components such as images, common names, and keys designed to appeal to students at all levels as well as interested users such as divers and aquarists. Museum exhibits will be created based on research results, one at the University of Kansas Natural History Museum, and one, entitled "Cnidarian Diversity in the Oceans" that will be part of the new Oceans Hall, due to open at the National Museum of Natural History in 2008. A website and classroom poster (in both English and Spanish) integrated with the latter exhibit will be created in collaboration with a K-12 educator supported through NSF's Research Experience for Teachers program.