Evolutionary dynamics in complex phenotype spaces

复杂表型空间中的进化动力学

• 批准号: 216921-2013
• 负责人: Doebeli, Michael
• 金额: $ 5.76万
• 依托单位: University of British Columbia
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2014
• 资助国家: 加拿大
• 起止时间: 2014-01-01 至 2015-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=546476
• 关键词: Evolutionary; dynamics; complex; phenotype; spaces

40 years ago, the realization that ecological dynamics can be very complicated, and indeed chaotic, has revolutionized ecology. In contrast, in evolutionary biology the prevalent perspective still is of evolution as an equilibrium process, converging towards optimally adapted phenotypes. This perspective is correct for simple scenarios, when frequency-independent selection acts on simple phenotypes. In most organisms, many phenotypic properties combine in complicated ways to determine ecological interactions, and hence frequency-dependent selection. Therefore, it is natural to consider evolution due to frequency-dependent selection acting simultaneously on many different phenotypes. For example, diversity is more likely to evolve when phenotypes are multi-dimensional. In general, however, very little is known about the theory of evolutionary dynamics due to frequency-dependent selection in complex phenotype spaces. In particular, it is not known how often oscillatory and chaotic evolutionary dynamics are expected to occur. My research aims to address these fundamental questions. I use mathematical models for evolution due to competition, predation and mutualism to classify the different types of evolutionary dynamics occurring in multi-dimensional phenotype spaces, and to assess how often oscillatory and chaotic dynamics occur in such models. Also, I will use whole-genome sequencing of the fossil (frozen) record of microbial populations evolving in nutritional environments of varying complexity to test the effect of phenotypic complexity on evolutionary dynamics. This will show empirically whether in more complex environments, diversification becomes more likely, and evolutionary dynamics exhibit larger fluctuations and become less predictable. Finally, I will use mathematical models to investigate the effect of phenotypic complexity on another fundamental evolutionary problem: the evolution of cooperation. Taken together, the proposed research has the potential to alter our view of general evolutionary processes. If complex dynamics is common in high-dimensional phenotype spaces, then our view of evolution as an equilibrium process must be fundamentally revised.

40年前，意识到生态动力学可能非常复杂，而且确实是混乱的，它彻底改变了生态学。相反，在进化生物学中，普遍的观点仍然是一种均衡过程，趋向于最佳适应表型。当独立于频率的选择作用于简单表型时，这种观点对于简单场景是正确的。在大多数生物体中，许多表型特性以复杂的方式结合起来，以确定生态相互作用，从而确定频率依赖性选择。因此，由于频率依赖性选择在许多不同的表型上同时起作用，因此自然而然地考虑进化。例如，当表型是多维时，多样性更有可能发展。然而，通常，由于复杂表型空间中频率依赖性选择而导致的进化动力学理论知之甚少。特别是，尚不清楚预期发生振荡和混乱的进化动力学的频率。我的研究旨在解决这些基本问题。由于竞争，捕食和互惠主义，我使用数学模型进行进化来对多维表型空间中发生的不同类型的进化动力学进行分类，并评估此类模型中振荡和混乱动力学的频率。另外，我将使用在不同复杂性的营养环境中演变的微生物种群的化石（冷冻）记录的全基因组测序，以测试表型复杂性对进化动力学的影响。从经验上讲，这将显示在更复杂的环境中，多样化的可能性更大，而进化动力学表现出更大的波动，并且变得较低。最后，我将使用数学模型来研究表型复杂性对另一个基本进化问题的影响：合作的演变。综上所述，拟议的研究有可能改变我们对一般进化过程的看法。如果复杂的动力学在高维表型空间中很常见，那么我们对进化作为平衡过程的看法必须从根本上进行修订。