The semi-aquatic brains of seals, does the return to water lead to predictabl e anatomical changes?

在这个项目中，我们的目标是确定水环境的强度，对哺乳动物大脑的进化，通过调查半水生食肉动物，鳍足类。我们将确定鳍足类动物的大脑是否与分类学上相关的陆地食肉动物或环境相关的完全水生的鲸鱼更相似。我们采集了5只斑海豹、2只斯特勒海狮、4只熊和2只浣熊的标本。 使用3T MRI扫描仪扫描所有大脑进行结构分析。对海马体积和脑体积数据进行处理，并对4种海马进行免疫组化。我们的初步研究结果表明，鳍足类有相对较小的campi相比，陆地食肉动物。此外，半水生的鳍足类动物成年后海马神经发生减少。这些结果与我们之前在鲸鱼身上观察到的结果一致。

In this project we aim to determine the strength of aquatic environment, on the evolution of the mammalian brain by investigating the semi-aquatic carnivores, the pinnipeds. We will determine whether the pinniped brain is more similar to the taxonomically related terrestrial carnivores or the environmentally related fully aquatic whales. We collected specimens of 5 spotted seals, 2 Steller sea lions, 4 bears and 2 racoons. All brains were scanned for structural analysis using a 3T MRI scanner. The data of hippocampal volume and brain volume has been processed and hippocampi of all 4 species have been subjected to immunohistochemistry. Our preliminary results demonstrate that pinnipeds have relative smaller hippocampi compared to terrestrial carnivores. Furthermore the semiaquatic pinnipeds have a reduced adult hippocampal neurogenesis. These results are in line with the findings we previously observed in whales.