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：测试石炭纪棘皮动物的地貌、寿命和地理范围之间的关系这项研究将集中于环境和生物地理因素在棘皮动物进化成功中的作用，棘皮动物是古生代最多样化和最丰富的海洋无脊椎动物之一。下石炭统(354-314英里))岩石在其进化史上记录了菠萝科属多样性的顶峰。进化的成功是通过化石记录中的分类寿命来衡量的。目前对进化成功原因的理解还不完全，但现有证据表明，与环境广度(泛欧地形)和地理范围呈正相关。支持这种相关性的数据对于古生代海洋无脊椎动物来说是有限的。因此，对早石炭世海鞘动物的分析将更严格地检验这种相关性，并拓宽我们对海洋无脊椎动物地貌、寿命和地理范围之间关系的理解。这项研究将对北美和欧洲这两个化石记录最好的地区的海百合类群(亚目)内的平均地层(寿命)、环境(古地形)和地理范围进行比较。这项研究将包括北美密西西比期(早石炭世)的Kinderhookian至Merameciian早期，以及西欧早石炭世相当的图尔奈期至Visean中期。将通过评估所有已知物种的正确属名来确定属的地层和地理范围。同时，将列出两大洲各属的环境分布数据，以计算每个属--包括大陆内和洲际--的全地形指数值。这项研究的结果将直接影响进化论，因为它试图解释地球上的生命历史。从这项研究中获得的大量数据集将有助于阐明环境和地理在决定普通长寿方面的作用，并最终有助于阐明群体长寿在定义进化成功方面的作用。

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.