Rudolph the red-nosed reindeer is the star of Santa's sleigh team, but the song about the creature has made all of use believe Rudolph's a male.
Eidenburgh University professors Gerald Lincoln and David Baird say it's impossible that Rudolph is a male, as male reindeer shed their antlers before mid-December.
Other than females, castrated males are the only reindeer to keep their horns through Christmas.
Professor Lincoln adds, "Rudolph could be a castrated male, or a female. I think it's nicest to think that Rudolph was a female!"