It's relatively rare to see a redhead — just 1% to 2% of humans are natural gingers. So, you might do a double-take if you see a man sporting a reddish or even a full-blown red beard, even though he ...

Many Irish men who are not redheads still grow red or reddish beards, a phenomenon known as "gingerbeard" that affects almost two in five men. Experts say it comes down to how genes control two ...