Divergent host plant adaptation and reproductive isolation between ecotypes of Timema cristinae walking sticks
Divergent host plant adaptation and reproductive isolation between ecotypes of Timema cristinae walking sticks
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DOI：
10.1086/510634
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发表时间：
2007-02-01
影响因子：
2.9
通讯作者：
Nosil, Patrik
中科院分区：
文献类型：
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作者：
Nosil, Patrik
理论和实证研究表明，趋异自然选择可以促进生殖隔离的进化。三个尚未解决的问题涉及的类型的生殖障碍，地理的作用，以及决定的进展程度的因素完全物种形成。在这里，我综合研究Timema cristinae寄主植物生态型来解决这些问题。该方法是比较不同的生态和地理情景之间的多重生殖障碍的大小，其中每一个场景中的人口对是复制的单位。将该方法应用于T. cristinae揭示了不同的宿主适应可以促进不同生殖障碍的进化，包括那些不是固有生态的障碍。在parapatry基因流往往限制分歧，与性隔离的加强显着的例外。因此，地理影响了物种形成的进程，但并没有以同样的方式影响所有的生殖障碍。对任何一对分类群的研究往往只能捕捉物种形成过程的某些阶段。例如，T. cristinae生态类型是不完整的，因此只研究了物种形成完成之前的阶段。需要对该属内更多不同分类群进行研究，以确定完成物种形成的因素。
dTheoretical and empirical studies have demonstrated that divergent natural selection can promote the evolution of reproductive isolation. Three unresolved questions concern the types of reproductive barriers involved, the role of geography, and the factors determining the extent of progress toward complete speciation. Here I synthesize studies of Timema cristinae host plant ecotypes to address these issues. The approach is to compare the magnitude of multiple reproductive barriers among different ecological and geographic scenarios, where pairs of populations within each scenario are the unit of replication. Application of this approach to T. cristinae revealed that divergent host adaptation can promote the evolution of diverse reproductive barriers, including those that are not inherently ecological. Gene flow in parapatry tended to constrain divergence, with the notable exception of the reinforcement of sexual isolation. Thus, geography affected progress toward speciation but did not influence all reproductive barriers in the same way. Studies of any single pair of taxa often capture only certain stages of the speciation process. For example, reproductive isolation between T. cristinae ecotypes is incomplete, and so only the stages before the completion of speciation have been examined. Studies of more divergent taxa within the genus are required to determine the factors that complete speciation.