Data for: Position in the plant size hierarchy is not heritable

<p><span>The rate of fitness evolution is largely determined by the amount of genetic variation for fitness in the population. In many plant populations, a few large individuals often occur alongside many more, smaller individuals. In annual plants, size is highly correlated with fitness. The contribution of genetic variation to position in the plant size hierarchy has not been investigated. We genotyped individuals at opposing positions in the plant size distribution in a natural population of the annual plant <em>Impatiens</em> <em>capensis</em> (Jewelweed). No significant genetic variation for position in the size hierarchy was detected when population structure was accounted for. This result suggests that the rate of evolution for increased plant fitness is constrained by low levels of standing genetic variation.</span></p>