• allozymes;
  • Avena barbata;
  • ecotypes;
  • local adaptation;
  • QTL;
  • RIL

Both ecological and molecular methods have been applied to the study of locally adapted populations. While Clausen et al. (1940) were the pioneers of field transplant studies, the work of Robert Allard et al. on the invasive species Avena barbata is a classic example of using molecular evidence to infer adaptation via correlation of particular alleles with environmental gradients. In a new study published in this issue of Molecular Ecology, Latta (2009) combines ecological methods (reciprocal environment studies) with quantitative genetic techniques (recombinant inbred lines and quantitative trait analysis) to provide new evidence for local adaptation within this well known system. The conclusions are orthogonal to the original hypothesis, and instead, provide evidence that factors other than local adaptation were likely responsible for the historically observed patterns. This new evidence suggests that one ecotype is generally more fit than the other in both a moist and a dry environment, and accordingly, it appears to be increasing in frequency in historically surveyed populations.