A rare mutation among the Bajau people lets them stay underwater longer: natural selection at the PDE10A gene has increased spleen size in the Bajau, providing them with a larger reservoir of oxygenated red blood cells.

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A rare mutation among the Bajau people lets them stay underwater longer: natural selection at the PDE10A gene has increased spleen size in the Bajau, providing them with a larger reservoir of oxygenated red blood cells.