Coordinated evolution of brain size, structure and eye size in Trinidadian killifish

Brain size, brain architecture, and eye size vary extensively in vertebrates. However, the extent to which the evolution of these components is intricately connected remains unclear. Trinidadian killifish, Anablepsoides hartii, are found in sites that differ in the presence and absence of large predatory fish. Decreased rates of predation are associated with evolutionary shifts in brain size; males from sites without predators have evolved a relatively larger brain and eye size than males from sites with predators. Here, we evaluated the extent to which the evolution of brain size, brain structure, and eye size covary in male killifish. We utilized wild-caught and common garden reared specimens to determine if specific components of the brain have evolved in response to differences in predation and to determine if there is covariation between the evolution of brain size, brain structure, and eye size. We observed consistent shifts in brain architecture in second generation common garden...脊椎动物的脑容量、脑结构与眼部尺寸广泛存在差异。然而，这些特征的演化之间究竟存在何种紧密的内在关联，目前仍未明晰。特立尼达青鳉（Anablepsoides hartii）的栖息环境存在两类：一类分布有大型掠食性鱼类，另一类则无此类掠食者。捕食压力降低与脑容量的演化改变存在关联：相较于来自有掠食者生境的雄性个体，无掠食者生境的雄性个体演化出了相对更大的脑容量与眼部尺寸。本研究旨在评估雄性特立尼达青鳉的脑容量、脑结构及眼部尺寸的演化之间存在何种程度的协同变化。我们利用野生捕获及经同质园（common garden）繁育的标本，旨在探究大脑的特定结构是否因捕食压力差异发生演化，并验证脑容量、脑结构与眼部尺寸的演化是否存在协同关联。我们在第二代同质园繁育的样本中观察到了脑结构的一致性改变……