A GENETIC INTERPRETATION OF ECOLOGICALLY DEPENDENT ISOLATION
A GENETIC INTERPRETATION OF ECOLOGICALLY DEPENDENT ISOLATION
复制标题
生态依赖性隔离的遗传学解释
DOI：
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发表时间：
2001
期刊：
影响因子：
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通讯作者：
M. Whitlock
中科院分区：
文献类型：
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作者：
H. Rundle;M. Whitlock
摘要杂种可能会遭受降低的健身，因为他们之间的生态位（生态依赖的隔离）和作为一个结果的内在遗传不相容性之间的亲本基因组（生态独立的隔离）。尽管遗传不相容性是所有物种形成理论的共同点，但生态依赖隔离是物种形成生态模型的独特预测。这种预测可以使用相互移植，其中各种基因型的适合性进行评估，在父母的栖息地进行测试。在这里，我们扩展了Lynch（1991）的数量遗传模型，以包括两个亲本环境。我们问是否有足够的实验设计存在检测生态依赖隔离。模型的分析表明，通过在两个亲本环境中使用两个回交，可以估计环境特异性加性遗传效应，同时校正任何内在的遗传隔离。环境特异性优势效应也可以通过将F1和F2包括在相互移植中来估计。相反，只将F1或F2代与亲本物种进行比较的相互移植不能将生态依赖与内在遗传隔离分开。因此，F1或F2杂种相对于亲本物种的适应性降低不足以证明生态物种形成。该模型突出了重要性，确定遗传和生态机制的贡献，混合健身，如果有关物种形成机制的推论。通讯编辑：H. A. Orr
Abstract Hybrids may suffer a reduced fitness both because they fall between ecological niches (ecologically dependent isolation) and as a result of intrinsic genetic incompatibilities between the parental genomes (ecologically independent isolation). Whereas genetic incompatibilities are common to all theories of speciation, ecologically dependent isolation is a unique prediction of the ecological model of speciation. This prediction can be tested using reciprocal transplants in which the fitness of various genotypes is evaluated in both parental habitats. Here we expand a quantitative genetic model of Lynch (1991) to include two parental environments. We ask whether a sufficient experimental design exists for detecting ecologically dependent isolation. Analysis of the model reveals that by using both backcrosses in both parental environments, environment-specific additive genetic effects can be estimated while correcting for any intrinsic genetic isolation. Environment-specific dominance effects can also be estimated by including the F1 and F2 in the reciprocal transplant. In contrast, a reciprocal transplant comparing only F1s or F2s to the parental species cannot separate ecologically dependent from intrinsic genetic isolation. Thus, a reduced fitness of F1 or F2 hybrids relative to the parental species is not sufficient to demonstrate ecological speciation. The model highlights the importance of determining the contribution of genetic and ecological mechanisms to hybrid fitness if inferences concerning speciation mechanisms are to be made. Corresponding Editor: H. A. Orr