Does phenotypic plasticity help or hinder rapid adaptation?

表型可塑性是指单个基因型在环境变化的影响下产生不同表型的能力。如果一个种群中所有的基因型都以同样的方式对环境变化作出反应，那么可塑性就会减少选择所作用的可遗传表型变异，并减缓适应。相反，如果所有的基因型都以非常不同的方式反应，可塑性可能会加速快速适应。因此，可塑性是帮助还是阻碍了适应，取决于选择对种群所面临的压力源形成可塑性反应的时间。在这种情况下，与适应污染物等“新的”人为环境相比，可塑性对种群适应气候变化方面的快速适应的影响可能大不相同，气候变化方面一直是种群进化史的一部分。克隆生物使我们能够验证这一假设，因为我们可以将相同的基因组暴露在不同的环境中，并比较它们对个人、群体和社区的影响。该项目的目的是验证这样一个假设，即对气候相关压力源的塑料反应会减缓适应，而对“新”环境的塑料反应会加速适应。这些发现的相关性将通过比较实验室中暴露于压力源组合的复制种群的适应率来确定。虽然有一些实验室证据表明，新环境暴露了隐遗传变异的选择，但我们仍然很少了解这在自然种群中的相关性，在自然种群中，表型取决于对许多环境异质性的适应性和非适应性可塑性反应。了解这些相互作用对于预测种群如何应对环境变化至关重要。该课程采用多种方法，包括实地和实验室技能、显微镜、图像分析和高级统计分析，以调查快速适应的机制。

Phenotypic plasticity is the ability of a single genotype to make different phenotypes inresponse to environmental variation. If all genotypes in a population respond to anenvironmental change in the same way plasticity can diminish the heritable phenotypicvariation that selection acts on and slow down adaptation. In contrast, if all genotypesrespond in very different ways, plasticity may speed up rapid adaptation. Whether or notplasticity helps or hinders adaptation therefore depends on the time that selection has had toshape the plastic responses of a population to the stressor it is facing. In this context, theeffect that plasticity has on rapid adaptation could be quite different for populations adaptingto aspects of climate change that have always been part of a population's evolutionaryhistory, compared with adaptation to 'novel' anthropogenic environments such as pollutants.Clonal organisms allow us to test this hypothesis because we can expose the same genomesto different environments and compare the effect that they have on individuals, populationsand communities.The aim of this project is to test the hypothesis that plastic responses to climate-relatedstressors slows down adaptation whereas plastic responses to 'novel' environments speeds itup. The relevance of these findings will be determined by comparing rates of adaptation inreplicated populations exposed to combinations of stressors in the laboratory. Although thereis some laboratory evidence that novel environments expose cryptic genetic variation toselection, we still have little understanding of how relevant this is in natural populations,where phenotypes depend on adaptive and non-adaptive plastic responses to manyenvironmental heterogeneities. Understanding these interactions is critical for predicting howpopulations respond to environmental change. This studentship applies diverse approaches,including field and laboratory skills, microscopy, image analysis, and high-level statisticalanalysis to investigate the mechanisms underpinning rapid adaptation.