Mechanisms of reinforcement in natural and simulated polymorphic populations
Mechanisms of reinforcement in natural and simulated polymorphic populations
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自然和模拟多态群体的强化机制
DOI：
10.1111/j.1095-8312.2008.01048.x
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发表时间：
2008
影响因子：
1.9
通讯作者：
Roman Yukilevich
中科院分区：
文献类型：
--
作者：
P. Nosil;Roman Yukilevich
强化物种形成是一个过程，即对杂交种的选择驱动了增强的交配前生殖隔离的进化。工作集中在不同的交配偏好（交配），但交配前的隔离也可以通过各种迁移修改行为，如不同的栖息地偏好。这两种不同的强化机制的相对重要性尚不清楚。最近的一个理论模型（Yukilevich-True模型）发现，这些机制之间的相对固定概率可能会有所不同。此外，自然种群的Timema cristinae手杖表现出的变化（多态性）在这两种机制，产生的问题，预计在固定之前的等位基因频率的模式，在物种形成过程的早期阶段。在本研究中，我们报告：（1）新的分析研究的固定概率之间的相关性，为替代性交配和迁移修改的Yukilevich-True模型;（2）新的模拟研究等位基因频率的多态群体;（3）经验模式的强化T。cristinae在理论预测的背景下。两种类型的模拟结果一致，表明强化的结果取决于选择的强度。在弱选择下，两种机制都不可能强化。在中间选择下，有利于一种机制的上升和固定的条件也有利于另一种机制的上升和固定。然而，竞争性交配比迁移修饰更容易进化。种群T。cristinae经历了这样的中间选择，支持了这些预测。在强选择下，迁移修饰的进化通常通过减少种群间的迁移来干扰选择性交配的进化，从而减少选择性交配。等位基因频率与固定概率结果的一致性表明，在物种形成过程的不同阶段，预期会有类似的强化模式。© 2008 The Linnean Society of伦敦，Biological Journal of the Linnean Society，2008，95，305-319。
Reinforcement speciation is the process whereby selection against hybrids drives the evolution of enhanced pre-mating reproductive isolation. Work has focused on divergent mating preferences (assortative mating) but pre-mating isolation can also arise via various migration modification behaviours, such as divergent habitat preferences. The relative importance of these two different mechanisms of reinforcement remains unclear. A recent theoretical model (Yukilevich–True model) found that relative fixation probabilities between these mechanisms can vary. Additionally, natural populations of Timema cristinae walking-sticks exhibit variation (polymorphism) in both mechanisms, generating questions about the patterns expected for allele frequencies prior to fixation, during the early stages of the speciation process. In the present study, we report: (1) new analyses examining the correlation between fixation probabilities for assortative mating and migration modification in the Yukilevich–True model; (2) novel simulations examining allele frequencies in polymorphic populations; and (3) empirical patterns of reinforcement in T. cristinae in the context of theoretical predictions. Simulations of both types yielded congruent results, revealing that the outcome of reinforcement was dependent on the strength of selection. Under weak selection, reinforcement by either mechanism is unlikely. Under intermediate selection, the conditions favoring the rise and fixation of one mechanism favored the rise and fixation of the other. However, assortative mating evolved somewhat more readily than migration modification. Populations of T. cristinae, which experience such intermediate selection, supported these predictions. Under strong selection, the evolution of migration modification generally interfered with the evolution of assortative mating by decreasing migration between populations, thereby reducing selection for assortative mating. Congruence of the results for allele frequencies versus fixation probabilities suggests that similar patterns of reinforcement are expected during different stages of the speciation process. © 2008 The Linnean Society of London, Biological Journal of the Linnean Society, 2008, 95, 305–319.