Kuijper Bram, Johnstone Rufus A, Townley Stuart
Environment and Sustainability Institute, University of Exeter, Penryn, United Kingdom; Behaviour and Evolution Group, Department of Zoology, University of Cambridge, Cambridge, United Kingdom; CoMPLEX, Centre for Mathematics and Physics in the Life Sciences and Experimental Biology, University College London, London, United Kingdom; Department of Genetics, Evolution and Environment, University College London, London, United Kingdom.
Behaviour and Evolution Group, Department of Zoology, University of Cambridge, Cambridge, United Kingdom.
PLoS Comput Biol. 2014 Apr 10;10(4):e1003550. doi: 10.1371/journal.pcbi.1003550. eCollection 2014 Apr.
There is a growing interest in predicting the social and ecological contexts that favor the evolution of maternal effects. Most predictions focus, however, on maternal effects that affect only a single character, whereas the evolution of maternal effects is poorly understood in the presence of suites of interacting traits. To overcome this, we simulate the evolution of multivariate maternal effects (captured by the matrix M) in a fluctuating environment. We find that the rate of environmental fluctuations has a substantial effect on the properties of M: in slowly changing environments, offspring are selected to have a multivariate phenotype roughly similar to the maternal phenotype, so that M is characterized by positive dominant eigenvalues; by contrast, rapidly changing environments favor Ms with dominant eigenvalues that are negative, as offspring favor a phenotype which substantially differs from the maternal phenotype. Moreover, when fluctuating selection on one maternal character is temporally delayed relative to selection on other traits, we find a striking pattern of cross-trait maternal effects in which maternal characters influence not only the same character in offspring, but also other offspring characters. Additionally, when selection on one character contains more stochastic noise relative to selection on other traits, large cross-trait maternal effects evolve from those maternal traits that experience the smallest amounts of noise. The presence of these cross-trait maternal effects shows that individual maternal effects cannot be studied in isolation, and that their study in a multivariate context may provide important insights about the nature of past selection. Our results call for more studies that measure multivariate maternal effects in wild populations.
预测有利于母体效应进化的社会和生态环境的研究兴趣日益浓厚。然而，大多数预测都集中在仅影响单一性状的母体效应上，而在存在一系列相互作用性状的情况下，母体效应的进化却知之甚少。为了克服这一问题，我们在波动环境中模拟了多元母体效应（由矩阵M表示）的进化。我们发现，环境波动的速率对矩阵M的性质有重大影响：在缓慢变化的环境中，后代被选择具有与母体表型大致相似的多元表型，因此矩阵M的特征是具有正的主导特征值；相比之下，快速变化的环境有利于具有负主导特征值的矩阵M，因为后代倾向于具有与母体表型有显著差异的表型。此外，当对一个母体性状的波动选择相对于对其他性状的选择在时间上延迟时，我们发现了一种显著的跨性状母体效应模式，即母体性状不仅影响后代的同一性状，还影响其他后代性状。此外，当对一个性状的选择相对于对其他性状的选择包含更多随机噪声时，大的跨性状母体效应会从那些经历最少噪声的母体性状中进化而来。这些跨性状母体效应的存在表明，个体母体效应不能孤立地进行研究，并且在多元背景下对它们的研究可能会提供有关过去选择本质的重要见解。我们的结果呼吁开展更多在野生种群中测量多元母体效应的研究。
