Analysis of Speciation Mechanisms in an Adaptive Radiation

长期以来，适应性辐射一直被认为是自然选择和物种形成的主要例子。为了理解导致这些辐射的过程，需要对物种之间的关系进行系统发育重建。然而，适应性辐射通常发生得非常快，因此传统的系统发育重建方法往往失败。这项拟议的研究将调查对多个基因的3‘-非翻译区的DNA测序是否将为一种特别快速的适应性辐射的系统发育重建提供必要的数据，这种辐射是在柱花属中进行的。在对表达基因的3‘端进行测序后，将设计特异的聚合酶链式反应引物来扩增编码和非编码基因区域。然后，将对这些基因区域进行测序，以确定多个物种的基因序列，并进行系统发育重建。理解产生生物多样性的过程对于理解如何维持生物多样性至关重要。适应性辐射代表着显著多样化的实例，但如果没有关于其物种进化关系的信息，在了解其起源方面就不可能取得什么进展。这项拟议的研究将调查一种适用于重建大范围分类群关系的技术。

Adaptive radiations have long been recognized as prime examples of natural selection and speciation. To understand the processes that bring about these radiations requires a phylogenetic reconstruction of the relationships among the species. However, adaptive radiations usually occur extremely rapidly and therefore traditional methods of phylogenetic reconstruction often fail. The proposed research will investigate whether DNA sequencing of the 3'-untranslated region of multiple genes will provide the data necessary for the phylogenetic reconstruction of a particularly rapid adaptive radiation, that in the columbine genus Aquilegia. After sequencing the 3' ends of expressed genes, specific PCR primers will be designed to amplify both coding and non-coding gene regions. These gene regions will then be sequenced for multiple species of Aquilegia and a phylogenetic reconstruction will be made. Understanding the processes that generate bio-diversity is essential to understanding how bio-diversity can be maintained. Adaptive radiations represent instances of remarkable diversification yet without information on the evolutionary relationships of their species, little progress can be made on understanding their origin. The proposed research will investigate a technique that would be applicable to reconstructing relationships for a wide range of taxa.