Figure 3.

Patterns of pairwise F_ST for control (blue) and immune (red) genes. Levels of F_ST reflect D. melanogaster’s spread out of its ancestral range in sub-Saharan Africa (represented by the Zimbabwe population). Flies likely spread to Europe and Asia 10,000 years ago, only reaching Tasmania and North America through colonization by European populations within the last 200 years. Population samples are from Zimbabwe (Z); Beijing (B); the Netherlands (N); Ithaca, New York (I); and Tasmania (T).