Abstract：
Phenotypic plasticity is critical for organismal performance and can evolve in response to natural selection. Brain morphology is often developmentally plastic, affecting animal performance in a variety of contexts. However, the degree to which plasticity of brain morphology evolves has rarely been explored. Here we use Trinidadian guppies (Poecilia reticulata), which are known for their repeated adaptation to high-predation (HP) and low-predation (LP) environments, to examine the evolution and plasticity of brain morphology. We exposed second-generation offspring of individuals from HP and LP sites to two different treatments: predation cues and conspecific social environment. Results show that LP guppies had greater plasticity in brain morphology compared to their ancestral HP population, suggesting that plasticity can evolve in response to environmentally divergent habitats. We also show sexual dimorphism in the plasticity of brain morphology, highlighting the importance of considering sex-specific variation in adaptive diversification. Overall, these results may suggest the evolution of brain morphology plasticity as an important mechanism that allows for ecological diversification and adaptation to divergent habitats.
摘要：
表型可塑性对于生物性能至关重要，并且可以响应自然选择而进化。大脑形态通常是发育可塑性的，在各种情况下影响动物的表现。然而,大脑形态的可塑性演变的程度很少被探索。在这里，我们使用特立尼达孔雀鱼（Poeciliareticulata），以反复适应高捕食（HP）和低捕食（LP）环境而闻名，检查大脑形态的演变和可塑性。我们将HP和LP位点个体的第二代后代暴露于两种不同的治疗方法：捕食线索和特定的社会环境。结果表明，与祖先HP种群相比，LP孔雀鱼在大脑形态上具有更大的可塑性，这表明可塑性可以随着环境差异的栖息地而进化。我们还显示了大脑形态可塑性的性二态性，强调在适应性多样化中考虑性别特异性变异的重要性。总的来说,这些结果可能表明大脑形态可塑性的进化是一个重要的机制，允许生态多样化和适应不同的栖息地。
