Inference of the demographic history of <i>P</i>. <i>teres</i> f. <i>teres</i> populations shows an ancient split coinciding with barley domestication and early migration.

A) Development of speciation scenarios across three analyses steps and using approximate Bayesian computation and Random Forest analyses implemented in DIY ABC-RF version 1.0. B) The most probable hypothetical evolutionary scenario of the migration routes of P. teres f. teres across the Middle East, North Africa, Europe, and North America based on the results of three sequential DIY ABC-RF analyses. The parameter “P” indicates the posterior probability of the most probable scenario. In paratheses are shown the probabilities of the different group containing the most probable demographic scenario (see Methods). We considered a classic invasion scenario for the topology building where each derived population passes through a bottleneck as it gives rise to a new population. Predicted time over the current Ne of the most ancestral population (NAzb) values inferred with random forest are shown. The 90% CI values for each parameter is provided in parentheses. C) Changes in effective population size for all P. teres f. teres populations were estimated with MSMC2. The axes were scaled with a mutation rate of 4.5 x 10−7 per site per generation, and one generation per year. The estimated time of barley domestication is indicated with an arrow. D) Relative cross-coalescence rate for all pairs of populations. Five runs of seven randomly selected individuals per population per run were performed. Shown here, is the trend line fit between the five runs. Gray area around the line indicates the 95% confidence interval. The arrow indicates the estimated time of barley domestication.