Experimental studies on ecological and genetic complexity in adaptation

为什么自然界如此多样？可以说，这个问题仍然是生物学中尚未解决的核心问题之一。我的研究旨在提供一个答案。我的目的是为生物多样性的起源和命运提供一个普遍的、基于经验的理论。我用微生物模型系统通过实验来检验进化论的基础理论，这种技术被称为实验进化。这种方法使我能够实时跟踪多样性的出现和命运，并与基因组测序相结合，使我能够确定负责适应和多样化的基因变化。本文提出的研究问题是，当面对比以前考虑的更复杂的生态和遗传系统时，我们现有的模型在解释适应性多样化模式方面表现得如何。

Why is the natural world so diverse? Arguably, this question remains one of the central unresolved problems in biology. My research aims to supply an answer. My aim is to provide a general, empirically-grounded theory for the origins and fate of biodiversity. I use microbial model systems to test foundational theories in evolution through experiment to do this, a technique known as experimental evolution. This approach allows me to track the emergence and fate of diversity in real time and, in combination with genome sequencing, allows me to identify the genetic changes responsible for adaptation and diversification. The research proposed here asks how well our existing models fare at explaining patterns of adaptive diversification when confronted with more ecologically and genetically complex systems than have been considered previously. Our short-term objectives are (1) to evaluate the impact of network topology on adaptation in metapopulations and, (2) test predictions on how the structure of fitness landscapes the mapping of genotype to fitness changes during adaptation. More specifically, we ask whether spatial structure, the network of sub-populations connected by dispersal, impacts the outcome of selection in an otherwise uniform environment. What if the environment is also spatially variable, in the sense that different patches contain different resources or stresses, a situation that should promote the evolution of diversity? How good are models of adaptation at predicting which sequence of genetic changes cause adaptation? This work is motivated by foundational problems, and so will contribute to basic knowledge in evolution, genetics, and ecology and training at least 17 highly qualified people, from undergraduate through to PhD, over the course of this grant. However, the lens through which much of this research happens is the management of pathogenic microbes, especially in regards to antimicrobial resistance. It has long been appreciated that many of the challenges we face in treating infectious disease have evolution at their core. This work constitutes a first step towards evaluating evolutionary theories that can inform practical solutions associated with the treatment and management of infectious disease.