COLLABORATIVE RESEARCH: Evolutionary Success in Marine Invertebrates: Testing the Relationships between Eurytopy, Longevity, and Geographic Range in Carboniferous Crinoids

合作研究：海洋无脊椎动物的进化成功：测试石炭纪海百合的广食性、寿命和地理范围之间的关系这项研究将集中在海百合（棘皮动物）进化成功中的环境和地理因素的作用，海百合是古生代海洋无脊椎动物中最多样化和丰富的类群之一。 早石炭世（3.54亿年至3.14亿年）前）岩石记录了海百合属的多样性在其进化历史的高峰。 进化的成功是通过化石记录中的分类寿命来衡量的。 目前对进化成功的原因的理解是不完整的，但现有的证据表明与环境广度（广食性）和地理范围呈正相关。 支持这种相关性的数据是有限的古生代海洋无脊椎动物。 因此，分析石炭纪早期海百合，初步工作支持这样的相关性，将更严格地测试的相关性，并扩大我们的理解之间的关系，广食性，寿命和海洋无脊椎动物的地理范围。 这项研究将比较北美和欧洲这两个化石记录最好的地区之间海百合类（亚目）的平均地层（寿命）、环境（广食性）和属的地理范围。 该研究将包括北美密西西比期（早石炭纪）的Kinderhookian至早期Meramecian时代和西欧早石炭纪的Tournaisian至中期Visean时代。 将通过评价所有已知物种以确定属的地层和地理范围。 同时，将两大洲各属的环境分布数据制成表格，以计算陆内和洲际各属的广食性指数值。 这项调查的结果将直接影响进化论，因为它致力于解释地球生命的历史。 从这项研究中获得的广泛的数据集将有助于阐明环境和地理在确定通用寿命，并最终在定义进化成功的群体寿命中的作用。

COLLABORATIVE RESEARCH: Evolutionary Success in Marine Invertebrates: Testing the Relationships between Eurytopy, Longevity, and Geographic Range in Carboniferous CrinoidsThis study will focus on the role of environmental and biogeographic factors in the evolutionary success of crinoids (echinoderms), one the most diverse and abundant groups of marine invertebrates during the Paleozoic. Lower Carboniferous (354 to 314 m.y. ago) rocks record the peak of crinoid generic diversity during their evolutionary history. Evolutionary success is measured by taxonomic longevity in the fossil record. Current understanding of reasons for evolutionary success is incomplete, but available evidence indicates a positive correlation with environmental breadth (eurytopy) and geographic range. Data supporting this correlation are limited for Paleozoic marine invertebrates. Thus, analysis of Early Carboniferous crinoids, where preliminary work supports such a correlation, will more rigorously test the correlation and broaden our understanding of the relationships between eurytopy, longevity, and geographic range in marine invertebrates. The research will compare the average stratigraphic (longevity), environmental (eurytopy), and geographic ranges of genera within crinoid groups (suborders) between North America and Europe, the two regions with the best fossil record. The study will include the Kinderhookian to early Meramecian epochs of the Mississippian Period (Early Carboniferous) of North America and the equivalent Tournaisian to middle Visean epochs of the Early Carboniferous of western Europe. Stratigraphic and geographic ranges of genera will be determined by evaluating all known species for correct generic assignment. Simultaneously, data on environmental distribution will be tabulated for genera on both continents to calculate a eurytopy index value for each genus, both intracontinental and intercontinental. Results of this investigation will bear directly on evolutionary theory as it endeavors to explain the history of life on Earth. The extensive data set derived from this study will help elucidate the roles of environment and geography in determining generic longevity and, ultimately, group longevity in defining evolutionary success.