The ecological determinants of adaptive diversity in macroevolutionary radiations

进化生物学的一个主要悬而未决的问题是，生态条件通常在很短的时间间隔内发生变化，如何才能导致数百万年来稳定的进化模式。这个问题很难解决，因为不可能对发生在宏观进化时间尺度上的过程进行受控实验。在我的研究中，我将通过仔细研究一个自然的宏观进化实验来克服这个问题：热带蜥蜴在岛屿和大陆栖息地的重复进化辐射。变态蜥蜴(Anolis属)在几千万年的时间里，在相似和不同的生态环境中独立地发生了多次多样性。通过在宏大的进化实验中将这些辐射中的每一次作为个体复制，我能够测试关于生态学如何塑造大规模生物多样性进化的各种假说。*对于这项工作，我的第一个目标将是使用遗传工具重建所有约400种动物的系统发育(即关系和进化历史)。然后，我的实验室将使用这个历史框架来测试宏观进化过程的相互竞争的模型是否可以解释我们今天在这些蜥蜴身上观察到的由此产生的身体形式的多样性。接下来，我们将专注于确定对宏观进化影响最大的最接近的因素。具体地说，我们将再次使用系统发育框架来比较地理景观和生态群落在生物适应性多样性产生方面的相对重要性。为了我们的最终目标，我们将调查人类运输外来物种如何改变了动物的基本多样性模式，我们将寻求预测，由于人类活动，未来的多样性决定因素将如何不同于过去的那些。*这项研究的目标是通过解决进化论中一个长期悬而未决的问题来促进我们对生态学和进化的理解。该项目还将对生物多样性保护产生实际效益。我们关于引进物种的工作将为识别与贸易有关的物种威胁提供一个一般的预测框架，并将对加拿大和世界各地的生物多样性管理人员具有价值。**

A major unanswered question in evolutionary biology is how ecological conditions, which often change over very short time intervals, can result in evolutionary patterns that are stable for millions of years. This question is difficult to address because it is not possible to conduct controlled experiments on processes that occur over macroevolutionary timescales. In my research, I will overcome this problem through careful investigation of a natural macroevolutionary experiment: replicated evolutionary radiations of tropical lizards in both island and mainland habitats. Anole lizards (genus Anolis) have independently diversified many times over tens of millions of years in both similar and different ecological settings. By treating each of these radiations as an individual replicate in a grand macroevolutionary experiment, I am able to test a wide variety of hypotheses about how ecology shapes the evolution of large-scale biodiversity.******For this work, my first objective will be to use genetic tools to reconstruct the phylogeny (i.e., the relationships and evolutionary history) of all ~400 species of anoles. My lab will then use this historical framework to test whether competing models of the macroevolutionary process can explain the resulting diversity of body forms that we observe in these lizards today. We will next focus on identifying the proximate factors that most influence macroevolution. Specifically, we will again use a phylogenetic framework to compare the relative importance of the geographic landscape versus the ecological community for generating adaptive diversity in organisms. For our final objective, we will investigate how the transport of exotic species by humans has altered fundamental diversity patterns in anoles, and we will seek to predict how, as a result of human activities, the future determinants of diversity will differ from those of the past.******The goal of this research is to advance our understanding of ecology and evolution by addressing a longstanding, unanswered question in evolutionary theory. This project will also have applied benefits for biodiversity conservation. Our work on introduced species will provide a general predictive framework for identifying trade-associated threats to species, and will be of value to stewards of biodiversity in Canada and worldwide.**