Paleoecological Setting of Eocene Echinoderms at Seymour Island, Antarctic Peninsula

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9315927 Blake 9413295 Aronson This award supports a study of echinoderm fossils from the Eocene La Meseta Formation of Seymour Island in the Antarctic Peninsula. This formation represents shallow marine conditions and it contains one of the most diverse fossil echinoderm assemblages in the world. The Seymour Island echinoderm fauna has characteristics more like Paleozoic echinoderm communities than like the great majority of other Cenozoic shallow water communities. Current thinking suggests that morphologically novel marine organisms originated primarily in near shore, heterogeneous environments, and then expanded to offshore, more homogeneous environments. After the Paleozoic, this pattern of near shore-offshore pattern is thought to have been driven largely by predation pressure. The La Meseta echinoderm occurrences suggest that the community reorganization that began in the Mesozoic may not have been completed until the early Cenozoic. This research will extend the taxonomic work on the echinoderms from Seymour Island and it will evaluate the significance of predation in stelleroid and crinoid populations. This information will allow a comparison with other echinoderm occurrences, both fossil and modern, and will provide a rare view of echinoderm paleoecology. Specifically, this research will allow an important test of the hypothesis that predation pressure in shallow-marine near-polar environments during the Eocene was an important forcing mechanism for echinoderm communities. ***