Dechmann Dina K N, Safi Kamran
Leibniz Institute for Zoo- and Wildlife Research, Alfred-Kowalke-Strasse 17, 10315 Berlin, Germany.
Biol Rev Camb Philos Soc. 2009 Feb;84(1):161-72. doi: 10.1111/j.1469-185X.2008.00067.x.
Comparative studies of brain size have a long history and contributed much to our understanding of the evolution and function of the brain and its parts. Recently, bats have been used increasingly as model organisms for such studies because of their large number of species, high diversity of life-history strategies, and a comparatively detailed knowledge of their neuroanatomy. Here, we draw attention to inherent problems of comparative brain size studies, highlighting limitations but also suggesting alternative approaches. We argue that the complexity and diversity of neurological tasks that the brain and its functional regions (subdivisions) must solve cannot be explained by a single or few variables representing selective pressures. Using an example we show that by adding a single relevant variable, morphological adaptation to foraging strategy, to a previous analysis a correlation between brain and testes mass disappears completely and changes entirely the interpretation of the study. Future studies should not only look for novel determinants of brain size but also include known correlates in order to add to our current knowledge. We believe that comparisons at more detailed anatomical, taxonomic, and geographical levels will continue to contribute to our understanding of the function and evolution of mammalian brains.
脑容量的比较研究有着悠久的历史，为我们理解大脑及其各部分的进化和功能做出了很大贡献。最近，蝙蝠越来越多地被用作此类研究的模式生物，因为它们物种数量众多、生活史策略高度多样，并且对其神经解剖学有相对详细的了解。在此，我们提请注意比较脑容量研究中固有的问题，强调局限性，但也提出替代方法。我们认为，大脑及其功能区域（细分区域）必须解决的神经学任务的复杂性和多样性，无法用代表选择压力的单个或少数变量来解释。通过一个例子我们表明，在先前的分析中加入一个单一的相关变量，即对觅食策略的形态适应，脑容量与睾丸质量之间的相关性就会完全消失，并完全改变研究的解释。未来的研究不仅应该寻找脑容量的新决定因素，还应该纳入已知的相关因素，以增加我们目前的知识。我们相信，在更详细的解剖学、分类学和地理层面上的比较，将继续有助于我们理解哺乳动物大脑的功能和进化。
