What are the benefits of having blonde hair?
Some believe it provided an evolutionary advantage in the competition for mates but no evidence to support this has been found.
Interestingly, blonde hair is more common in young children and women but can also be caused by sun exposure and your genes.
Blonde hair is most common in Europeans with lightly-coloured skin but it’s also found in regions where skin is darkly pigmented. For example, in Melanesia, about 5–10% have naturally blonde hair.
It was always thought that blonde hair was introduced by colonising europeans but a recent study of people from the Solomon Islands in Melanesia has shown the blonde hair has evolved separately in this population.
The genetic basis underlying blonde hair was investigated by comparing the genomes of blonde and dark-haired Solomon Islanders. This revealed that the islanders’ blonde hair was linked to a single mutation in the TYRP1 gene, that encodes an enzyme influencing pigmentation in mice and humans. Several genes are known to contribute to blonde hair coloration in Europeans, but not TYRP1.
A larger DNA comparision in individuals from 52 populations around the world, found that the TYRP1 mutation is probably unique to the Melanesia region. About one-quarter of Solomon Islanders carry the mutation in their genomes, but it is recessive, so an individual needs two copies to be blonde.
To end, here’s a list of Blonde medical terminology and a smart blonde joke (unusual, I know).
Bubba and Junior were standing at the base of a flagpole, looking up.
A woman walked by and asked what they were doing. “We’re supposed to find the height of the flagpole,” said Bubba, “but we don’t have a ladder.” The woman took a wrench from her purse, loosened a few bolts, and laid the pole down. Then she took a tape measure from her pocket, took a measurement and announced, “Eighteen feet, six inches,” and walked away.
Junior shook his head and laughed. “Ain’t that just like a dumb blonde! We ask for the height, and she gives us the length!”
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