Fig. 2

The number of parallelisms exceeds expectations under mutation-only null models. a The observed number of parallelisms in each pairwise paralog alignment is plotted against the number of one-to-one aligned polymorphic sites that segregate alternative alleles. b The observed number of parallelisms in a random set of 100 paralog alignments is plotted against the expected number of parallelisms derived from coalescent simulations. In both plots, the dashed red line corresponds to the null expectation assuming equal mutation rates to all nucleotides (y = 2×)