Brains are very plastic both in response to phenotypic diversity and to larger evolutionary trends. Differences between taxa cannot be easily attributed to either factors. Comparative morphological data on higher taxonomic levels is scarce especially in ray-finned fishes. Here we show the great diversity of brain areas of more than 150 species of ray-finned fishes by volumetric measurements using block face imaging. We found that differences among families or orders are more likely due to environmental needs than to systematic position. Most notable changes are present in the brain areas processing sensory input (chemosenses and lateral line vs. visual system) between salt- and freshwater species due to fundamental differences in habitat properties. Further, some patterns of brain volumetry are linked to characteristics of body morphology. There is a positive correlation between cerebellum size and body depth, as well as the presence of a swim bladder. Since body morphology is linked to ecotypes and habitat selection, a complex character space of brain and body morphology and ecological factors together could explain better the differentiation of species into their ecological niches and may lead to a better understanding of how animals adapt to their environment.


中文翻译：

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射线鳍鱼大脑的多样性

大脑对表型多样性和更大的进化趋势的反应都非常可塑。类群之间的差异不能轻易归因于任何一个因素。较高分类水平的比较形态学数据很少，尤其是在辐鳍鱼中。在这里，我们通过使用块面成像的体积测量来展示 150 多种射线鳍鱼大脑区域的巨大多样性。我们发现家庭或订单之间的差异更有可能是由于环境需求而不是系统位置。由于栖息地特性的根本差异，咸水和淡水物种之间处理感官输入（化学感应和侧线与视觉系统）的大脑区域存在最显着的变化。此外，一些大脑容量模式与身体形态特征有关。小脑大小和身体深度以及鱼鳔的存在之间存在正相关关系。由于身体形态与生态型和栖息地选择有关，大脑和身体形态以及生态因素的复杂特征空间可以更好地解释物种向其生态位的分化，并可能导致更好地了解动物如何适应环境。