Fig. 3. D statistics with two SEs for the whole genome and fit to the classical phylogeny of these taxa.

On the basis of transversions with transitions removed. The green dot is for D not significantly different from zero, and red dotted lines mark the size of deviation of significant values. The dashed vertical line represents no introgression, a D = 0. For each test, the four taxa are arranged in a tree (((H₁, H₂)H₃)H₄), where H₄ is the Arctic cod as the outgroup and every other taxon is rotated into the position of potential introgressor (H₃, second from the right), as well as into the positions of potential recipients of introgression (H₁ and H₂, the two leftmost taxa of each line). A positive D implies that H₂ is closer to the potential introgressor (H₃) than H₁ is. The opposite is true for a negative D. The figure was made with admixturegraph (58).