"It might surprise the public, but not ancient DNA geneticists," says Mark Thomas, a scientist at the University College London. Following suit is the theory that two people with blue eyes will automatically have a child with blue eyes due to the gene being recessive, rather than dominant.A recent facial reconstruction of a 10,000-year-old skeleton called the " Cheddar Man" has revealed a man with bright blue eyes, slightly curly hair, and dark skin. It’s long been believed that if someone has brown eyes – or what appear to be brown eyes – their chances of having a child with lighter eyes are slim. “It’s believed that’s how blue eyes came about, but it may just be the de-emphasis on the need for all the melanin,” Heiting said. In one study, he analyzed genes for eye color and identified what he believed to be a common mutation causing blue eye color. This would lead to light eyes in the affected individual their rarity may have made them more attractive and aided their natural selection within the population. “There was less need for all that melanin,” Heiting said.Īnother theory conceived by professor Hans Eiberg at the University of Copenhagen was that a mutation once switched off the ability of someone’s eye to produce melanin. While high levels of melanin – in eyes, hair, and skin – help protect people in hotter climates, like Africa, from UV radiation, the need for the protective pigment decreases as people move to locations with less sun. Regular marijuana use might affect vision, study says Marijuana use became more widespread in the 1960s, reflecting the rising counterculture movement.
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