Warning: This video contains language that some may find offensive.

While the blond-hair, blue-eyed look is often portrayed as the "ideal" all-American look, blue eyes are actually a genetic mutation. In fact, the majority of people had brown eyes prior to 10,000 years ago, according to BuzzFeed. 
Advertisement
Researchers at the University of Copenhagen discovered that everyone with blue eyes can be tracked back to a single ancestor, according to Science Daily. The researchers tracked down the genetic mutation that causes blue eyes to sometime between 6,000 and 10,000 years ago, 

Scientists believe that all people originally had brown eyes but that a genetic mutation on the OCA2 gene caused the body to produce less pigment, which resulted in blue eyes, according to Science Daily. 

Because different eye tones are based on the amount of melanin (pigment) the body produces, scientists concluded that everyone with blue eyes comes from the same ancestral line, "From this we can conclude that all blue-eyed individuals are linked to the same ancestor. They have all inherited the same switch at exactly the same spot in their DNA," Professor Hans Eiberg, of the University of Copenhagen's Department of Cellular and Molecular Medicine, told Science Daily. 

Scientists say that the "mutation" isn't good or bad, it just is. "It is one of several mutations such as hair colour, baldness, freckles and beauty spots which neither increases nor reduces a human's chance of survival, " according to Science Daily. 

Blue eyes are considered a recessive gene by biologists. This means that in order for a person to have blue eyes, both parents must pass on a gene for blue eyes. Scientists believe that about 1 in 6 Americans have blue eyes, according to The Tech.