Ecological and genetic mechanisms of adaptive radiation

我的研究计划的目的是揭示驱动适应性辐射的机制--来自共同祖先的新物种的快速起源和分化。地球上的许多物种(甚至大多数物种)都是在这种爆发期间出现的，所以它们是理解生命异常多样性的起源的关键。适应性辐射仍处于早期阶段的情况具有巨大的研究优势，因为进化速度加快，新物种仍在形成，中间形式仍然存在，进化事件经常重复，年轻物种仍有能力杂交。这些特征使我们能够通过结合观察、实验和遗传研究取得快速进展。*已经积累了许多理论来解释新物种是如何形成的，驱动它们彼此分化的机制，以及新物种如何继续存在。我在实验室的工作通过研究自然选择和遗传变异在三刺鱼物种复合体中的作用来测试这些基本想法，这些刺鱼生活在不列颠哥伦比亚省沿海的幼小湖泊和溪流中。这个系统包括一些地球上最年轻的物种。这个学习系统有很多研究的优势(它被称为进化的“超模”)。与合作者一起，我们开发了针对刺鱼的特殊遗传和实验工具。这使我们能够通过操纵自然选择的原因(例如，捕食)来检验基本假设，并通过跟踪由此产生的世代遗传变化来衡量进化。目前的提案描述了新的实验，这些实验特别侧重于竞争和行内捕食在物种起源及其同时分化方面的作用。*我们的工作有助于发展生物多样性科学的基本概念。这项工作将使人们更好地理解推动新物种快速起源的因素，并使它们能够在自然界中长期存在。我们的工作还提供了对生态系统在新物种崩溃时如何变化的更好的理解。其中一些工作具有立竿见影的实际效果。刺背物种对是我们大部分工作的重点，是公元前最濒危的鱼类群体，其中两对已经灭绝。所有这些都是联邦政府列出的濒危物种，我们关于物种起源和差异的工作继续为恢复计划提供信息。**

The aim of my research program is to uncover the mechanisms that drive adaptive radiation -- the rapid origin and divergence of new species from a common ancestor. Many (perhaps even most) species on earth have arisen during such bursts, so they are key to understanding the origins of life's extraordinary diversity. Cases of adaptive radiation still in their early stages have great advantages for study because the rate of evolution is sped up, new species are still forming, intermediate forms are still extant, evolutionary events are frequently repeated, and young species remain capable of hybridizing. These features allow us to make rapid progress using a combination of observational, experimental, and genetic studies. ******Much theory has accumulated to explain how new species form, the mechanisms driving their divergence from one another, and how new species continue to persist. Work in my lab tests these fundamental ideas by addressing the role of natural selection and genetic variation in a species complex of threespine stickleback fish, which inhabit young lakes and streams of coastal British Columbia. This system includes some of the youngest species on earth in any organism. This study system has many advantages for study (it has been called an evolutionary “supermodel”). With collaborators, we have developed exceptional genetic and experimental tools for stickleback. These allow us to test fundamental hypotheses by manipulating the causes of natural selection (for example, predation), and measure evolution by tracking the resulting genetic changes across generations. The current proposal describes new experiments that focus especially on the role of competition and intraguild predation on the origin of species and their simultaneous divergence. ******Our work contributes to the development of fundamental concepts in biodiversity science. The work will lead to a better understanding of the factors driving the rapid origin of new species, and that enable their long-term persistence in nature. Our work has also provided a better understanding of how ecosystems change when new species collapse. Some of this work has immediate practical benefits. The stickleback species pairs that are the focus of much of our work are the most highly endangered group of fishes in BC, with two pairs already extinct. All are federally listed Species at Risk, and our work on species origins and differences continues to inform recovery planning.**