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(A) All populations. (B) Lineage north. (C) Lineage south. (D) Sublineage NW. (E) Sublineage NE. (F) Sublineage S1. (G) Sublineage S2. The lines indicate the observed frequency of pairwise nucleotide differences between sequences, and the dashed lines are the expected distribution based on a model of sudden population expansion.
