Evolutionary-branching lines and areas in bivariate trait spaces
Evolutionary-branching lines and areas in bivariate trait spaces
复制标题
双变量特征空间中的进化分支线和区域
DOI：
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发表时间：
2012
期刊：
影响因子：
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通讯作者：
U. Dieckmann
中科院分区：
文献类型：
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作者：
Hiroshi C. Ito;U. Dieckmann
目的：进化分枝是由频率依赖的生态相互作用引起的进化多样化过程。在这里，我们展示了如何预测发生的进化分支的双变量性状时，人口的方向发展。
方法：根据自适应动力学理论，我们假设低突变率和小突变步长。在此基础上，我们概括的条件进化分支点的条件进化分支线和地区，描绘的区域的性状空间中，进化分支，可以预期，尽管人口仍然发展方向沿着这些线和这些地区内。为了评估我们的新条件进化分支线和区域提供的预测质量，我们分析了三个生态进化模型与双变量性状空间，比较预测的进化分支线和区域与数值计算的进化动力学中进化分支的实际发生。在这三个例子中，一个表型的适应性受到频率依赖的资源竞争和/或捕食者-猎物相互作用的影响。
结论：在无限小突变步长的限制下，二元性状空间中的进化分支只能发生在进化分支点，即，进化的种群在没有任何定向选择的情况下经历破坏性选择。相反，当突变步长是有限的时，进化分支也可以沿着进化分支线发生，即，其中与这些线正交的分裂选择相对于沿着它们的沿着方向选择足够强。此外，这种进化分支线嵌入在进化分支区域中，这些区域描绘了所有双变量性状组合，当突变率低时，进化分支可以发生，而突变步长是有限的。我们的分析表明，进化分支线和地区是很好的指标，在定向进化种群的进化分支。我们还证明了并非所有的进化分支线和区域都包含进化分支点，因此即使在根本不包含进化分支点的性状空间中，进化分支也是可能的。
Aims: Evolutionary branching is a process of evolutionary diversification induced by frequency-dependent ecological interaction. Here we show how to predict the occurrence of evolutionary branching in bivariate traits when populations are evolving directionally.
Methods: Following adaptive dynamics theory, we assume low mutation rates and small mutational step sizes. On this basis, we generalize conditions for evolutionary-branching points to conditions for evolutionary-branching lines and areas, which delineate regions of trait space in which evolutionary branching can be expected despite populations still evolving directionally along these lines and within these areas. To assess the quality of predictions provided by our new conditions for evolutionary branching lines and areas, we analyse three eco-evolutionary models with bivariate trait spaces, comparing the predicted evolutionary- branching lines and areas with actual occurrences of evolutionary branching in numerically calculated evolutionry dynamics. In the three examples, a phenotype's fitness is affected by frequency-dependent resource competition and/or predator-prey interaction.
Conclusions: In the limit of infinitesimal mutational step sizes, evolutionary branching in bivariate trait spaces can occur only at evolutionary-branching points, i.e., where the evolving population experiences disruptive selection in the absence of any directional selection. In contrast, when mutational step sizes are finite, evolutionary branching can occur also along evolutioary-branching lines, i.e., where disruptive selection orthogonal to these lines is sufficiently strong relative to directional selection along them. Moreover, such evolutionary- branching lines are embedded in evolutionary-branching areas, which delineate all bivariate trait combinations for which evolutionary branching can occur when mutation rates are low, while mutational step sizes are finite. Our analyses show that evolutionary-branching lines and areas are good indicators of evolutionary branching in directionally evolving populations. We also demonstrate that not all evolutionary-branching lines and areas contain evolutionary- branching points, so evolutionary branching is possible even in trait spaces that contain no evolutionary-branching point at all.
条件扩散和生殖隔离沿着环境梯度的演变。
影响因子：
2
作者：
Payne,JoshuaL;Mazzucco,Rupert;Dieckmann,Ulf
通讯作者：
Dieckmann,Ulf