Phylogenetic Relationships within the Phocoid Pinniped Clade

鳍足类是海洋哺乳动物中的一个重要类群，由海象、海狮和海豹组成。然而，它们彼此之间以及与其他哺乳动物之间的进化关系仍然不清楚。安娜丽莎·贝尔塔博士是一位脊椎动物古生物学家，研究化石和现存的管脚类动物的解剖学，目的是重建它们的进化史。她的研究还考虑了化石物种的功能能力，为该群体中行为的进化及其从陆地祖先的转变提供了独特的见解。贝尔塔博士计划利用化石的形态数据，继续她对鳍脚类动物进化关系的研究。目前的项目将重点放在海象的一个可能的姐妹群--Phcids上。将检查俄勒冈州沿海渐新世-中新世的头颅和后颅材料，并评估运动能力(主要是前肢和后肢推进)。该项目是对上一个奖项的合理扩展，该奖项支持对海象类鳍脚类动物(海象、海狮，但不是海豹)的研究。这项拟议的研究对广泛的科学受众具有影响。比较解剖学家和脊椎动物动物学家将欢迎来自早第三纪化石的新数据，以及主要哺乳动物群体进化关系的新重建。功能形态学家将在这项研究中寻找关于水生栖息地生活的替代适应的关键信息。进化生物学家将把这些发现与基于DNA序列数据的最新结果结合起来，从而对这一值得注意的群体有一个异常详细的了解。

Pinnipeds are an important group of marine mammals, comprising the walruses, sea lions, and seals. Nevertheless, their evolutionary relationships to each other and to other mammals remain unclear. Dr. Annalisa Berta is a vertebrate paleontologist studying the anatomy of fossil and living pinnipeds for the purpose of reconstructing their evolutionary history. Her research also considers the functional capabilities of fossilized species, providing unique insight into the evolution of behavior in the group, and its transformation from terrestrial ancestors. Dr. Berta proposes to continue her investigations into the evolutionary relationships among pinnipeds using morphological data from fossils. The present project will focus on the phocids, a possible sister-group to the walruses. Cranial and post-cranial material from the Oligocene- Miocene of coastal Oregon will be examined, and locomotor capabilities (principally forelimb versus hindlimb propulsion) estimated. This project represents a logical extension of a previous award that supported study of the otarioid pinnipeds (walruses, sea lions, but not seals). The proposed research has implications for a wide scientific audience. Comparative anatomists and vertebrate zoologists will welcome the new data derived from early Tertiary fossils, along with new reconstructions of evolutionary relationships of major mammalian groups. Functional morphologists will look to this study for critical information on alternative adaptations to life in aquatic habitats. Evolutionary biologists will integrate these findings with recent results based on DNA sequence data, resulting in an unusually detailed understanding of this noteworthy group.