Genetic divergence within the gambiae species complex. (a) An un-rooted neighbour-joining tree, calculated from pairwise K
between species averaged across loci. Branch lengths are to scale. The filled triangles illustrate the relative scale of diversity and divergence within the complex, such that the length of the triangle is half the divergence between haplotypes within species (i.e π
/2) and net divergence (K
) corresponds to branch-lengths that are not part of the triangle. (Note that population samples and thus π
were not available for An. quadriannulatus A and An. merus). (b)-(d) Neighbour-joining cladograms (i.e. topology only, branch-lengths uninformative) showing the unique alleles sequenced from three loci. Note that in all cases An. gambiae and An. arabiensis alleles are intermixed. (b) to (d) are control locus 14, SRPN7 and SRPN11, selected to illustrate a wide range of K
values between An. gambiae and An. arabiensis (K
= 0.51, 0.10 and 0.09, respectively).