Pollution Is Turning Sea Snakes Black for a Surprising Reason

by spotmydive

In the coral reefs of the Indo-Pacific, the waters of some areas are so polluted that turtle-headed sea snake have changed color in order to survive. Emydocephalus annulatus, live in the waters of Southeast Asia, Australia and New Caledonia. Some of them frequent polluted waters, near industrial and urban centers. French and Australian researchers have found that these marine reptiles wear a full black outfit, while usually they are striped. They also noticed that these species moulted much more often than others.

Copyright: Jim Catlin Photography

An adaptation to survive the pollution

Scientists then conducted skin analyzes of these animals and found that they contained a much higher concentration of toxins than individuals in unpolluted areas. This dark skin would allow urban marine snakes to reject heavy metals ingested, copper, lead, zinc, or others, whenever they moult. This is the phenomenon of industrial melanism. This is not the first case observed. Already in the nineteenth century, Biston betularia, a large night-flying moth with white wings speckled with black, which lived near the great British industrial centers, had been decorated with a black dress. This transformation allowed him to be confused with the darkness of the soot that covered the trees.