Mechanisms of adaptive radiation

适应性辐射是进化过程中的一个阶段，在此期间，新物种从一个共同的祖先迅速起源，并在饮食、栖息地、体型、行为和其他特征上进化出差异。这些事件被认为产生了许多生命的多样性。在过去的一二十年里，生物学家在了解适应性辐射的一般特征方面取得了显著的进展，但其潜在机制的许多细节仍不清楚。在我的实验室里，研究的是在不列颠哥伦比亚省沿海新形成的湖泊和溪流中生活的三刺鱼物种群中产生适应性辐射的原因。这个群体代表了正在进行的进化工作，它包括地球上一些最年轻的物种。它的许多特征使它易于研究（它被称为进化研究的“超模”）。在不同的湖泊中，大小、形状和行为的许多变化都在反复进化，生殖隔离进化的每个阶段（减少物种之间基因流动的特征——新物种进化的必要条件）都得到了体现。然而，种群可以在实验室中进行杂交，从而进行遗传和实验研究。大量的遗传资源最近被开发出来，包括一个完整的基因组序列，使它成为研究进化遗传基础的最佳系统之一。目前的建议利用这些优势来研究基因的自然选择，新物种起源和分化两个阶段的基因组变化，以及适应性辐射对生态系统的影响。这项工作扩大了与分子生物学家dr。Kingsley（斯坦福大学医学院）和Peichel（西雅图弗雷德·哈钦森癌症研究中心）已经取得了引人注目的发现，知识和工具的公开转移，以及对学生的高级培训。

Adaptive radiation is an episode in evolution during which new species originate rapidly from a common ancestor and evolve differences in diet, habitat, body size and shape, behavior and other traits. These episodes are thought to have given rise to much of life's diversity. Biologists have made outstanding progress over the last decade or two in understanding the general features of adaptive radiation, but many details of the underlying mechanisms are still obscure. Work in my lab addresses the causes of adaptive radiation in a species complex of threespine stickleback fish inhabiting young lakes and streams of coastal British Columbia. This group represents an evolutionary work-in-progress and it includes some of the youngest species on earth. It has many features make it amenable to research (it has been called a "supermodel" for evolutionary studies). Many changes in size, shape and behavior have evolved repeatedly in different lakes, and every stage in the evolution of reproductive isolation (traits that reduce gene flow between species -- a requirement for the evolution of new species) is represented. Yet, populations can be crossed in the lab, allowing genetic and experimental study. Substantial genetic resources have recently been developed for stickleback, including a complete genome sequence, making it one of the best systems known in which to investigate the genetic basis of evolution. The present proposal harnesses these advantages to investigate natural selection on genes, the genomic changes that underlie two stages in the origin and divergence of new species, and the effects that adaptive radiation has on ecosystems. The work expands collaborations with molecular biologists Drs. Kingsley (Stanford University Medical School) and Peichel (Fred Hutchinson Cancer Research Centre, Seattle) that have already yielded high-profile discoveries, open transfer of knowledge and tools, and advanced training of students.