Paleoecological Setting of Eocene Echinoderms at Seymour Island, Antarctic Peninsula

该奖项支持对南极半岛西摩岛始新世La Meseta组棘皮动物化石的研究。这个地层代表了浅海环境，它包含了世界上最多样化的棘皮动物化石组合之一。西摩岛棘皮动物动物群的特征更像古生代棘皮动物群落，而不像绝大多数其他新生代浅水群落。目前的想法表明，形态新颖的海洋生物主要起源于近岸，异质环境，然后扩展到近海，更均匀的环境。在古生代之后，这种近岸-近海模式被认为主要是由捕食压力驱动的。La Meseta棘皮动物的出现表明，始于中生代的群落重组可能直到新生代早期才完成。本研究将对西摩岛棘皮动物的分类学研究工作进行拓展，并将进一步评价捕食在石斛和海百合种群中的意义。这一信息将允许与其他棘皮动物的化石和现代事件进行比较，并将提供棘皮动物古生态学的罕见观点。具体来说，这项研究将为始新世浅海近极地环境中的捕食压力是棘皮动物群落的重要强迫机制这一假设提供重要的验证。* * *

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. ***