Research Starter Grant-Distribution of Genetic Variation in a Recently Derived Adaptive Trait

新生物技术的发展，如聚合酶链反应（PCR）和自动DNA测序，极大地促进了基础研究人员研究遗传变异的能力。新的与生物学家潜在的巨大相关性的遗传标记被称为单核苷酸多态性（SNPs）。为了验证这些理论，罗布·布伦菲尔德在他的国家科学基金会研究启动基金中，建议使用snp（发音为“snips”）来了解一群栖息在新世界热带雨林的被称为侏儒鸟的羽毛丰富的鸟类的进化史。先前对这些鸟类的研究发现，杂交和性选择在它们的物种形成中都起着重要作用。snp应该提供所需的解决方案，以确定哪个过程发挥了更重要的作用。布拉姆菲尔德的研究结果将为第二性特征的进化提供洞见（即，一些特征的进化是因为雌性喜欢它们，但这些特征并不一定是为了雄性的生存而进化的，雄孔雀的尾巴就是一个很好的例子）。由于第二性征可以通过雌性对这些特征的渴望直接进化，也可以通过与具有理想特征的近亲物种杂交间接进化，因此理清这些过程的相对重要性对于详细了解它们的进化至关重要。Brumfield的研究结果也将帮助其他生物学家确定SNPs是否代表了他们自己的自然种群进化研究的最佳遗传标记类型。

The development of new biotechnologies such as the polymerase chain reaction (PCR) and automated DNA sequencing have greatly facilitated the ability of basic researchers to study genetic variation. New genetic markers of potentially great relevance to biologists are known as single nucleotide polymorphisms (SNPs). To put them to the test, Robb Brumfield, in his NSF Research Starter Grant, proposes to use SNPs (pronounced "snips") to understand the evolutionary history of a group of brilliantly plumaged birds known as manakins that inhabit the rainforests of the New World Tropics. Previous studies of these birds have found that hybridization and sexual selection have both played important roles in their speciation. SNPs should provide the needed resolution to determine which process has played the more important role.Brumfield's results will provide insights into the evolution of secondary sexual traits (i.e. traits that evolve because females prefer them but which are not necessarily in the best interest of the male for survival; a male peacock's tail is a good example). Because secondary sexual traits could evolve directly by female's desiring those traits or indirectly through hybridization with a closely related species that has a desirable trait, disentangling the relative importance of those processes is critical for a detailed understanding of their evolution. Brumfield's results should also help other biologists determine whether SNPs represent the best type of genetic marker for their own evolutionary studies of natural populations.