REU/RIA: Reconstructing Articulate Brachiopod Phylogeny: Relevance to Hypotheses of Adaptation and Heterochrony

腕足类是海洋无脊椎动物，活着的物种相对较少，但有超过3000个属的丰富、多样化的化石记录。最近获得博士学位的桑德拉·卡尔森博士提议对他们的祖先-后代关系进行超家庭层面的研究。她将开始对一个关键的化石群--孔雀科--进行物种层面的研究，然后收集一个关于关节纲所有超级家族的形态特征的属级别的数据集，以便从文献中挑选出来。第一个子项目将帮助建立适当的分析特征，为第二个更高水平的研究奠定基础。人们对腕足类随时间演变和灭绝的模式进行了大量研究，但如果对该类群的分类构建错误，那么这些模式就是可疑的。这项拟议的研究将是第一次对海洋化石无脊椎动物的优势群体之一的进化关系进行明确、可重复的分析。由此产生的分类将提供前所未有的客观合成水平，并将为无脊椎动物古生物学家提供一个可遵循的模型。

Brachipods are marine invertebrates with relatively few living species but a rich, diverse fossil record of more than 3,000 genera. Dr. Sandra Carlson, a recent Ph.D., proposes a superfamily-level study of their ancestor-descendant relationships. She will begin a species-level study of a pivotal fossil group, the Porambonitacea, and then assemble a genus- level dataset on morphological characters for all superfamilies of the Articulata, to be culled from the literature. The first subproject will help to establish the proper characters for analysis, setting the stage for the second higher level study. Considerable research has been done on patterns of evolution and extinction of the Brachiopoda through time, but if the classification of the group is incorrectly constructed, then the patterns are suspect. The proposed study will be the first explicit, repeatable analysis of evolutionary relationships in one of the dominant groups of marine fossil invertebrates. The resulting classification will provide an unprecendented level of objective synthesis, and will provide a model for invertebrate paleontologists to follow.