Estimates from molecular data for the fraction of new nonsynonymous mutations that are adaptive vary strongly across plant species. Much of this variation is due to differences in life history strategies as they influence the effective population size ( N e ). Ample variation for these estimates, however, remains even when comparisons are made across species with similar values of N e . An open question thus remains as to why...

Critical to conservation efforts and other investigations at low taxonomic levels, DNA sequence data offer important insights into the distinctiveness, biogeographic partitioning and evolutionary histories of species. The resolving power of DNA sequences is often limited by insufficient variability at the intraspecific level. This is particularly true of studies involving plant organelles, as the conservative mutation rate of...