Fig. 6From: Parallel or convergent evolution in human population genomic data revealed by genotype networksBalancing selection can produce cycles. The example indicates a hypothetical diploid genotype where two nucleotide changes occur at position 10 and 20. Circles (nodes) correspond to genotypes. An edge connects two nodes if they differ by a single mutation. Lettering next to each node indicates the nucleotides at which two genotypes differ. Edge labels show changes required to create a genotype from its neighbor, e.g., “A20G” indicates a change from A to G at position 20 of the first haplotype of the hypothetical genotype. See text for detailsBack to article page