Gray Matters

The Mokens are a seafaring people who spend a great deal of their time in boats off the coast of Myanmar and Thailand. They live off the sea and get their food from diving deep underwater where there is little light. They have developed unusual underwater vision--twice as good as Europeans. This has enabled Mokens to gather shellfish at great depths without the aid of scuba gear. Without masks or scuba gear, they trained their brains and eyes to gather tiny shellfish and other food on the ocean floor at depths as low as 75 feet (23 meters). According to an online article in National Geographic News, deep water makes it difficult for the human eye to see. "But the Moken are able to accommodate, or muscularly change the shape of the eye's lens, in order to increase light refraction," the article says."It seems they have learned to control their accommodative response, such that they can voluntarily accommodate even in the blurry underwater environment." 

    

Dr. Dennis Charney, has studied how the brain responds to dramatic changes in peoples' environments. He believes that the brain can order the body to adapt to suite its needs in any environment. In the Moken's case, they have obviously trained their brains to adapt their vision to accommodate the underwater darkness.