The mechanisms and made-up-meanings behind being a redhead
Throughout history, humans with red hair have been associated with dishonesty, witchcraft, bad temperaments, unusual libidos, and even being souless. Some of these ideas are tied to depictions of Judas, even though the Bible never refers to his hair color, while others may be tied to early Greek prejudices against red-headed Thracians. Fortunately, as the father of two adorably copper-headed kids, interest in my children’s hair usually ranges from compliments, wishes for matching hair-dye or the endless curiosity about how both kids have hair that matches neither of their parents’ coloring.
Receptors for pale skin and maroon manes
Hair and skin color is determined by variations in melanocortin 1 receptors (MC1R), which in turn dictate the amounts of melanin pigments your body produces. Variations in MC1R that produce higher amounts of red and yellow, as opposed to brown, melanin can lead to blond or red hair. Importantly, those same MC1R variations also influence skin tone, leaving redheads with paler skin. As striking as red hair can be, the pale skin was probably the trait that was advantageous in some human ancestors. When humans first migrated to more northern latitudes, they needed more vitamin D from smaller amounts of sunlight, which was more easily obtained with light skin.
Obviously, with redheads estimated to represent less than one percent of the human race, not all pale skin comes with crimson hair. This is because the genes for red hair are recessive. When receiving DNA from your mother and father, you need two copies of the correct MC1R genes to actually grow red hair. Single copies of the gene will persist, but they’ll be overshadowed by dominant genes for darker coloration, like brown hair. Single copies of redhead MC1R genes can hint at their presence though, such as in redder beards of non-redheaded men. When questioned about the origins of my children’s coloring, bringing up my and my brother-in-law’s facial hair seems unsatisfactory to many people, but it’s the best evidence anyone can think of when explaining our genetic history.
Beyond cardinal coloration
This isn’t meant to reduce red hair to dry statistics concerning an acronym for a protein receptor though. It appears that those same genetic variations have set red heads up with unusual pain tolerances as well, with greater tolerances of some pain, like electrical stimulation, but lower tolerances for thermal pain. They’ve been found to require greater amounts of anesthetics as well.
Countering the social stigmas associated with redheads, Queen Elizabeth I of England flaunted her red hair, as it emphasized her connection to her father, Henry VIII, and thus her legitimacy on the throne. While she did have the coloring of a Tudor, she made a point of dying her wigs and even the tails of her horses red, almost like a personal brand. As she solidified her authority, courtiers began dying their beards red, basically pretending to be carriers of the MC1R variants that ran in Elizabeth’s family.
Source: The Scarlet Mark by Adam Rutherford and Hannah Fry, The Curious Cases of Rutherford & Fry
