Danish geneticists say everyone with blue eyes is not just related, but descended from one person.
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Brown, they say, is the default color for human eyes ... produced by melanin.
Blue eyes are caused by a genetic switch, programmed to suppress the melanin. It's a genetic mutation.
--snip--
The first blue eyed person was probably born near the Black Sea just 10,000 years ago when the entire population of the world was less than 50,000.
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