Colorplot of the DAPC of extended HGDP-CEPH data based on four inferred clusters. This colorplot represents the three principal components (PC) of the DAPC of extended HGDP-CEPH data, using the four clusters inferred by find.clusters (see Figure 6). Each dot corresponds to a sampled population. Each principal component is recoded as intensities of a given colour channel of the RGB system: red (first PC), green (second PC), and blue (third PC). These channels are mixed to form colours representing the genetic similarity of populations. Eigenvalues are not indicated, since there are only three PC in a DAPC based on four clusters.