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

海豹的半水生大脑，回归水中是否会导致可预测的解剖学变化？

• 批准号: 21K06404
• 负责人: PATZKE NINA
• 金额: $ 2.58万
• 依托单位: Hokkaido University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2021
• 资助国家: 日本
• 起止时间: 2021-04-01 至 2022-03-31
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-21K06404/
• 关键词: evolution; brain; comparative neuroanatomy; carnivores; pinnipeds; Brain; Pinnipeds; Evolution; Comparative neuroanatomy; Marine mammals

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.

在这个项目中，我们旨在通过研究半水栖食肉动物--管脚类动物来确定水环境的强度，对哺乳动物大脑的进化进行研究。我们将确定鳍足类的大脑与分类上相关的陆生食肉动物或与环境相关的完全水生鲸鱼中的哪一种更相似。我们采集了5只斑海豹、2只海狮、4只熊和2只浣熊的标本。使用3T磁共振扫描仪对所有的大脑进行结构分析扫描。对海马体和脑体积数据进行处理，并对4种动物的海马体进行免疫组织化学染色。我们的初步结果表明，与陆生食肉动物相比，鳍脚类动物的海马体相对较小。此外，半水栖夹脚类动物的成年海马神经发生减少。这些结果与我们之前在鲸鱼身上观察到的发现一致。