Figure 5

Effect of sequence divergence on power to detect sites evolving under positive selection. In the simulations, an average of 19 sites were assigned to evolve under positive selection (see text for simulation parameters). The level of sequence divergence estimated from the combined A. halleri, A. lyrata and Brassica sequences is 23.47 substitutions per codon. Results are averages over 5 independent replicates. The dashed vertical line represents the observed level of divergence estimated from the analysis of the 3 taxa combined.