Abstract：
We know that heritable variation is abundant, and that selection causes all but the smallest populations to rapidly shift beyond their original trait distribution. So then, what limits the range of a species? There are physical constraints and also population genetic limits to the effectiveness of selection, ultimately set by population size. Global adaptation, where the same genotype is favoured over the whole range, is most efficient when based on a multitude of weakly selected alleles and is effective even when local demes are small, provided that there is some gene flow. In contrast, local adaptation is sensitive to gene flow and may require alleles with substantial effect. How can populations combine the advantages of large effective size with the ability to specialise into local niches? To what extent does reproductive isolation help resolve this tension? I address these questions using eco-evolutionary models of polygenic adaptation, contrasting discrete demes with continuousspace.
摘要：
我们知道遗传变异是丰富的，这种选择导致除了最小的种群之外的所有种群迅速转移到其原始性状分布之外。那么,是什么限制了一个物种的范围？有物理限制，以及群体遗传对选择有效性的限制，最终由人口规模决定。全球适应，在整个范围内，相同的基因型受到青睐，当基于大量弱选择的等位基因时是最有效的，即使当地的恶魔很小，也是有效的，前提是有一些基因流动。相比之下,局部适应对基因流动敏感，并且可能需要具有实质性作用的等位基因。人口如何将有效规模大的优势与专注于当地生态位的能力结合起来？生殖隔离在多大程度上有助于解决这种紧张关系？我使用多基因适应的生态进化模型来解决这些问题，将离散的恶魔与连续的空间进行对比。
