大脑是对机体表现和健身至关重要的特征。迄今为止,大脑大小变化的进化研究主要利用了在物种或更高分类单元水平上应用的比较方法。然而,这些研究难以将因果关系与相关性分开。在另一个极端,对大脑可塑性的研究主要集中在人口内部模式上。在这些极端之间存在着跨人口研究,关注占据不同栖息地或选择性制度的同一物种种群之间的大脑大小变化。这些研究形成了一个快速增长的研究领域,它可以帮助我们理解大脑进化,为种间研究产生的想法提供一个试验台,以及有助于揭示遗传和环境因素对大脑大小和结构变化的相对重要性。除了提供首次对已发表的有关大脑大小变化的种内研究的深入综述外,我们讨论了大脑大小变化的跨群体研究的前景。特别是,以下主题值得进一步关注:(i)集中于解开基因贡献的研究,环境,以及它们对人群内部和人群之间大脑变异的相互作用,(ii)应用定量遗传工具评估遗传和环境因素对不同个体发育阶段大脑特征的相对重要性的研究,(iii)除了利用大脑大小的简单粗略估计外,未来的研究可以受益于神经解剖学的使用,神经组织学,和/或表征大脑大小和结构变化的分子方法。大脑大小和结构的演变是一个广泛研究的话题。然而,大多数研究是种间和比较的。在这里,我们总结了基于种群比较的种内研究的最新发展,并概述了这种方法的未来潜力。
The brain is a trait of central importance for organismal performance and fitness. To date, evolutionary studies of brain size variation have mainly utilized comparative methods applied at the level of species or higher taxa. However, these studies suffer from the difficulty of separating causality from correlation. In the other extreme, studies of brain plasticity have focused mainly on within-population patterns. Between these extremes lie interpopulational studies, focusing on brain size variation among populations of the same species that occupy different habitats or selective regimes. These studies form a rapidly growing field of investigations which can help us to understand brain evolution by providing a test bed for ideas born out of interspecific studies, as well as aid in uncovering the relative importance of genetic and environmental factors shaping variation in brain size and architecture. Aside from providing the first in depth
review of published intraspecific studies of brain size variation, we discuss the prospects embedded with interpopulational studies of brain size variation. In particular, the following topics are identified as deserving further attention: (i) studies focusing on disentangling the contributions of genes, environment, and their interactions on brain variation within and among populations, (ii) studies applying quantitative genetic tools to evaluate the relative importance of genetic and environmental factors on brain features at different ontogenetic stages, (iii) apart from utilizing simple gross estimates of brain size, future studies could benefit from use of neuroanatomical, neurohistological, and/or molecular methods in characterizing variation in brain size and architecture. Evolution of brain size and architecture is a widely studied topic. However, the majority of studies are interspecific and comparative. Here we summarize the recently growing body of intraspecific studies based on population comparisons and outline the future potential in this approach.