Spatial Analysis of Selection and Environmental Heterogeneity in Plant Populations

尽管有许多关于异质环境中进化的理论研究和对基因-环境相互作用的经验研究，但进化生物学家在很大程度上忽视了选择性环境中的变异模式。理论研究表明，异质环境中自然选择的结果主要取决于选择性环境中异质性的时空尺度。选择性环境是通过改变不同基因类型之间的适合度等级顺序(基因-环境交互作用)来定义的。研究人员将使用三种复制的无性基因作为“光度计”来测量环境异质性，以检验黄花灯盏花老种群中选择的空间和时间异质性。这三种基因型的幼苗将被种植在样本网格中，并监测其存活率和繁殖力。相对适合度的正空间自相关区域将定义选择性斑块，并将其与物理环境的变化进行比较。这项研究将产生第一张选择性景观地图，并将显示选择性表面在演替过程中的时间变化。

Despite numerous theoretical studies on evolution in heterogeneous environments and empirical studies of genotype- environment interactions, patterns of variation in the selective environment have been largely ignored by evolutionary biologists. Theoretical studies have shown that the results of natural selection in heterogeneous environments depend critically on the spatial and temporal scale of heterogeneity in the selective environment. The selective environment is define by changes rank order of fitness among genotypes (genotype-environment interactions). The investigators will examine spatial and temporal heterogeneity of selection in an oldfield population of Erigeron annuus, using three replicated asexual genotypes as "photometers" to measure environmental heterogeneity. Seedlings of the three genotypes will be planted in a sample grid and monitored for survivorship and fecundity. Areas of positive spatial autocorrelation of relative fitness will define the selective patch, and this will be compared to variation in the physical environment. This research will result in the first map of the selective landscape and will show temporal changes in the selective surface during succession.