DISSERTATION RESEARCH: The role of the Z-chromosome in the reproductive isolation of Passerina buntings (Aves: Cardinalidae)

模式生物之间杂交的研究对于我们理解新物种的形成非常重要，但不太可能完全捕捉自然系统中物种形成和杂交的过程。在拟议的项目中，研究人员调查了靛蓝（Passerina cyanea）和青蓝（P. amoena）buntings（Aves：Cardinalidae）之间生殖隔离的遗传基础，它们形成了一个杂交区，其繁殖范围重叠。初步数据表明，不同的遗传位点（线粒体，核常染色体，核Z-连锁）表现出跨杂交区的差异渐渗，并暗示Z-染色体对鸟类物种形成具有相对较大的影响。在这里，多个Z连锁基因座的遗传渐渗模式将与理论预测相结合，以检验旨在确定这些物种之间生殖隔离的基因的假设，除了研究将对我们理解密切相关的物种之间生殖隔离的演变产生影响之外，收集的数据还将允许评估P. cyanea的范围扩展。观测数据表明，蓝单胞菌的繁殖范围正在向西扩展，可能以P. amoena为代价，因此准确了解它们之间的杂交模式对于保护目的可能很重要。

Studies of hybridization between model organisms have been extremely important to our understanding of the formation of new species, but are unlikely to fully capture how speciation and hybridization proceed in natural systems. In the proposed project, the researchers investigate the genetic basis of reproductive isolation between Indigo (Passerina cyanea) and Lazuli (P. amoena) buntings (Aves: Cardinalidae), which form a hybrid zone where their breeding ranges overlap. Preliminary data suggest that different genetic loci (mitochondrial, nuclear autosomal, nuclear Z-linked) exhibit differential introgression across the hybrid zone and implicate the Z-chromosome as having a relatively large impact on avian speciation. Here, patterns of genetic introgression of multiple Z-linked loci will be combined with theoretical predictions to test hypotheses aimed at identifying genes contributing to reproductive isolation between these species.Beyond the impact the research will have on our understanding of the evolution of reproductive isolation between closely related species, the data collected will also allow for assessments of range expansion in P. cyanea. Observational data suggests the breeding range of P. cyanea is expanding westward, perhaps at the expense of P. amoena, such that an accurate knowledge of the patterns of hybridization between them may be important for conservation purposes.