Adaptation to natural variability and global change

这个项目是关于人类如何适应不断变化的环境。特别是，如果环境压力过大，一个种群必须通过自然选择来适应，否则就会灭绝。我们需要更多地了解“进化拯救”的过程，以便了解和预测种群将如何应对快速的环境变化。我提出了三个主要的调查领域。第一个问题涉及自然环境的可变性及其创造的选择模式。我将开发野生酵母作为生态学和进化的一般模型系统，以便利用酵母基因组技术的力量来研究自然种群的进化变化。其次，我将在实验室进行选择实验，以了解一个种群是否可能适应给定的压力。为了研究“实时进化”，这些实验使用了快速繁殖的微生物种群。它们是否适应应取决于压力的大小和种群中存在的遗传变异。最后，我将发现占全球初级生产很大一部分的浮游植物将如何对二氧化碳水平升高作出反应。这也将涉及使用单细胞藻类的实验室实验，以找出单个物种如何在几百代中适应，以及整个群落的物种组成如何变化。我们需要了解这些过程，以便预测下个世纪生态系统将如何应对全球变化。实验进化是研究一般原理和探索自然种群和群落未来行为的有力方法。

This project is about how populations become adapted to changing environments. In particular, if conditions become too stressful a population must either adapt by natural selection or become extinct. We need to know more about the process of 'evolutionary rescue' in order to understand and predict how populations will respond to rapid environmental change. I propose three main areas of inquiry. The first concerns the variability of natural environments and the pattern of selection it creates. I shall develop wild yeast as a general model system for ecology and evolution in order to use the power of yeast genomic technology to study evolutionary change in natural populations. Secondly, I will conduct selection experiments in the laboratory to find out whether a population is likely to adapt to a given stress. These experiments use microbial populations that turn over very rapidly in order to study 'evolution in real time'. Whether they adapt should depend on the magnitude of the stress and on the genetic variation present in the population Finally, I shall discover how phytoplankton, which are responsible for a large fraction of global primary production, will respond to elevated levels of carbon dioxide. This will also involve laboratory experiments using unicellular algae, to find out how individual species adapt over several hundred generations, and also how the species composition of whole communities changes. We need to understand these processes in order to predict how ecosystems will respond to global change in the course of the next century. Experimental evolution is a powerful way of both investigating general principles and probing the future behaviour of natural populations and communities.