Dissertation Research: Morphological Variation and Macroevolution in the Ostracode genus Poseidonamicus

该项目探讨了深海介形虫Poseidonamicus属4000万年历史中形态学的演变方式。化石和现代标本将使用扫描电子显微镜进行研究。介形虫甲壳的特征将使用获得的数字图像进行测量，并将重建随时间变化的形态变化模式。从这些数据中，将确定种群内变化更大的特征是否也更有可能进化。这项研究将是第一个使用化石记录来确定变化模式是否影响长期进化变化方向的研究。虽然这些模式的进化重要性在几代人的过程中得到了很好的理解，但尚不清楚性状变异性是否对长期进化有影响。一些研究人员认为，变异的模式应该会对进化过程产生偏见或限制，即使是在很长一段时间内。拟议中的研究利用一个具有丰富化石记录的分类群的进化历史来验证这些建议。

This project explores the manner in which morphology has evolved over the course of the 40 million year history of the deep-sea ostracode genus Poseidonamicus. Fossil and modern specimens will be studied using scanning electron microscopy. Features of the ostracode carapace will be measured using the digital images obtained, and patterns of morphological change over time will be reconstructed. From these data, it will be determined if features that are more variable within populations are also more likely to evolve. This study will be one of the first to use the fossil record to determine if patterns of variation affect the direction of long-term evolutionary change. While the evolutionary importance of these patterns is well understood over the course of a few generations, it is not clear whether trait variability matters for long-term evolution. Several researchers have suggested that patterns of variation should act to bias or constrain the course of evolution, even over long time stretches of time. The proposed research uses the evolutionary history of a taxon with a rich fossil record to test these suggestions.