South Pacific sea snakes are changing color in response to pollution run off from cities and military sites. Rather than camouflage, their new hue reflects the fact that dark skin is better at soaking up toxic trace metals, which get shed along with the skin.

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South Pacific sea snakes are changing color in response to pollution run off from cities and military sites. Rather than camouflage, their new hue reflects the fact that dark skin is better at soaking up toxic trace metals, which get shed along with the skin.