Local adaptation and maladaptation in spatially structured populations

大多数物种的种群分布在许多不同的地方，有时被栖息地较差的地区隔开，那里很少有个体出现。这些独立的种群通常至少在遗传上彼此不同，或者是偶然的（遗传漂变），或者是因为不同的地方环境选择不同的基因型（地方适应）。了解种群如何对这些空间异质性选择压力做出反应和分化是很重要的;例如，温暖环境中的种群可能是应对气候变化所带来挑战的遗传变异的必要来源。在这项资助中，我们将开发新的统计方法来衡量当地适应的基因组基础。我们将找到方法来纠正以前的方法中由一致有害突变引起的偏差。此外，空间异质性环境和物种范围边缘有害突变频率的随机增加都可以减缓种群在空间上的扩张速度。了解决定分布范围扩张速度的遗传因素对于理解和保护生物多样性至关重要--为什么我们看到的物种在该物种所在的地方而不是其他地方，我们如何阻止不受欢迎的入侵物种的传播，以及我们如何帮助本地物种的传播，因为它们正在适应气候变化。最后，我们将研究适应性表型可塑性的原因和后果（即当相同的基因型可以发展出与多个局部环境所需相匹配的表型时）。我们将研究在何种条件下表型可塑性的发展和描述可塑性的影响，发展的稳定性，鲁棒性和进化的物种。我们假设，不同的机制的可塑性和从环境中捕获的信息的模式将定性不同的功效和鲁棒性的影响。了解物种对异质环境的反应方式对于理解进化生物学的大多数方面至关重要，而对保护和气候变化挑战的适当反应取决于这些基础科学。

Most species have populations in many different locations, sometimes separated by areas of poor habitats where few individuals occur. These separate populations are usually at least somewhat genetically different from each other, either by chance (genetic drift) or because different local environments select for different genotypes (local adaptation). Understanding how populations respond to and diverge to these spatially heterogeneous selection pressures is important; for example, populations in warmer environment may be necessary sources of genetic variation to respond to the challenges caused by climate change. In this grant, we will develop new statistical approaches to measure the genomic basis of local adaptation. We will find ways to correct for biases in previous methods caused by uniformly deleterious mutations. Furthermore, both spatially heterogeneous environments and also random increases in the frequency of deleterious mutations at the edge of a species range can slow the rate of expansion of a population over space. Understanding the genetic factors that determine the rate of range expansion is crucial to understanding and protecting biodiversitywhy we see species in the places that the are and not elsewhere, how we can impede the spread of unwanted invasive species, and how we can aid the spread of native species as they move to adjust to climate change. Finally, we will study the causes and consequences of adaptive phenotypic plasticity (which is when the same genotype can develop a phenotype which matches what is required for multiple local environments). We will investigate under which conditions phenotypic plasticity evolves and describe the effects of plasticity on the developmental stability, robustness and evolvability of the species. We hypothesize that different mechanisms of plasticity and the modes of information capture from the environment will qualitatively differ in their efficacy and their effects on robustness. Understanding the ways in which species respond to heterogeneous environments is critical to understanding most aspects of evolutionary biology, and appropriate responses to conservation and climate change challenges depend on such basic science.**