Supplementary Figure 4: Linkage disequilibrium decays rapidly in honeybees.

The linkage disequilibrium (LD) between SNPs as measured using the r² estimator (y axes) is shown over increasing distance between the SNPs (x axes). (a) LD was found to decay quickly across the natural, domestic and Africanized populations. All populations have an r² value of <0.2 at 1 kb. The rate of decay of LD reflected population size and was most rapid in the African populations. The highest LD was found among European bees. The domestic lineages had an intermediate decay of LD. (b) The corresponding decay of LD after grouping the samples according to major continental groups—A (n = 30), C (n = 20), M (n = 30) and O (n = 20)—shows that r² is below 0.1 in all groups at distances of greater than 1,500 bp.