A new study looking into the reason why there are a large number of redheads in Britain suggests that the country's gloomy weather could be why it is the most red-headed nation in the world.
Provisional statistics indicate that between two and six percent of northwest Europeans are redheads as compared to an average of one or two percent in the world population.
But in the UK the numbers are much higher, with 13 percent of Scots, 10 percent of the Irish, and six percent of individuals in England having red hair.
A project by BritainsDNA, a company that tests DNA to reveal an individual's ancient ancestry, is currently looking at 4,000 test cases and hopes to explain early next year exactly why Britain has so many redheads.
It has a test that can tell who carries the red hair gene variant, which can be hidden for years before appearing in a child without warning because both parents have the gene.
Carriers pass it to 50 percent of their children, even if their spouse is not a carrier, which means red hair can be inherited for many generations unseen.
When a carrier has children with another carrier, it can then appear in their children "apparently out of nowhere".
Alistair Moffat, the rector of St Andrews University and one of the founders of BritainsDNA, said vitamin D from sunshine made most Africans dark-skinned, because of an excess of sun, and most Europeans light skinned.
Red hair, which is characteristic of people with very fair skin, freckles and intolerance to sunshine, should in theory appear most often in the far north of Europe.
However, according to researchers Britain may be the most red-headed part of the world simply because it gets more cloud than Scandinavia because of its maritime climate.
In Sweden, the average daily number of sunshine hours is 5.4, while in Scotland it is 3.1.
Mr Moffat said the "simplest explanation might turn out to be the best".
"Those who actually have red hair only need to look in the mirror but very many more carry a redhead gene variant but don't know they have it and could pass it on to their children. We aim to discover this hidden story of the red headed nation," the Telegraph quoted Moffat as saying.
"At least 1.6 million Scots carry a red-head gene variant, and most are unaware that they do. But the place where most carry the red headed variants may well not be in Scotland.
"In Ireland about 10 per cent have red hair, but it appears that a staggering 46 per cent are carriers of the red head variants. For England, the estimate is 6 per cent, but this is highly provisional and there are no current figures available for the number of carriers," he added.