Genome wide patterns of ancestry in an emerging hybrid lineage of sculpins (Cottus, Pisces)

由于遗传方法的应用已成为非模式物种的可能，越来越多的研究致力于自然杂交的案例。这一过程因其可能解释进化新颖性的出现而受到关注。除此之外，可以利用杂交种来确定亲本物种之间进化差异的遗传基础，因为不同的性状在杂交后代中分离，在那里可以使用适当的遗传和统计方法来识别它们。到目前为止，在动物身上还缺乏关于杂交确实影响进化变化的彻底证明。这项研究集中在一个可能的杂交物种形成的案例中，两种鱼(Cottus)杂交产生了一个具有新的生态潜力的杂交谱系，以入侵受干扰的栖息地。大规模并行测序将被应用于进行全基因组筛选，以确定与杂交成功相关的遗传因素。当混合血统被证明是生态成功的遗传基础时，就可以支持杂交影响进化过程的观点。事实上，杂交世系和当地亲本物种之间的杂交仍在继续，这一事实可以用于适合度分析，从而能够评估杂交基因在自然环境中的进化意义。

Since the application of genetic methods has become possible for non-model species, an increasing number of studies are devoted to cases of natural hybridization. This process receives attention for its potential to explain the emergence of evolutionary novelty. Aside of this, hybrids can be exploited to identify the genetic basis for evolutionary divergence between the parental species because differentiated traits segregate in hybrid offspring where they can be identified using appropriate genetic and statistical approaches. Up to now, a thorough demonstration that hybridization indeed affects evolutionary change is still lacking in animals. This study focuses on a likely case of hybrid speciation in which two species of fish (Cottus) have interbred to give rise to a hybrid lineage with a new ecological potential to invade disturbed habitats. Massively parallel sequencing will be applied to perform a genomewide screen to identify genetic factors that are associated with the hybrids success. Support for the idea that hybridization affects evolutionary processes, can be obtained when a mixed ancestry is demonstrated for the genetic basis for ecological success. The fact that interbreeding continues among the hybrid lineage and the parental species locally can be exploited for fitness assays which permits to assess the evolutionary significance of hybrid genotypes in natural settings.