Figure 4.

Different positions in the genome have different neutralities. We sampled 10⁷ genotypes for g = 2 (a) and g = 3 (b) and 10³ genotypes for g = 4 (c) and g = 5 (d), and measured r_i for i = 1, …, 20. For each i we then computed 〈r_i〉 and plotted them versus genomic position. Note the high robustness of the first position in the promoter region, and the low robustness in the coding regions. (Online version in colour.)