Led by a reindeer named Rudolph, some might assume the sleigh-pullers that form the backbone of Santa Claus's mighty toy-distribution operation are all male.

But they'd be wrong, according to Nova Scotia Museum zoologist Andrew Hebda, who says the speed that allows the man in red to deliver presents around the world comes from an all-female team of flying reindeer.

Andrew Hebda

Andrew Hebda is a zoologist with the Nova Scotia Museum. (CBC)

Hebda said the North American name for reindeer is caribou. The term reindeer is used in some European countries and describes a slightly smaller animal that tends to be domesticated.

Both male and female caribou have antlers. During the breeding season, males use their antlers to fight and win over mates, but the antlers fall off in the fall.

"The females hang onto them until just before they give birth, which will tend to be March, April, May, depending on where you are. So therefore the only caribou left with antlers this time of year are female," said Hebda. 

In paintings, movies and sculptures, Santa's reindeer are usually shown with antlers.

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Caribou is the North American name for reindeer, according to Hebda. (Government of British Columbia handout/Canadian Press)

Hebda said the flying reindeer Santa uses bear a striking resemblance to the woodland caribou that used to roam Nova Scotia. The last of the woodland caribou disappeared from mainland Nova Scotia in the 1920s, although there were unconfirmed sightings reported as late as the 1950s.

Climate change forced the caribou to move north to find a better food supply, said Hebda. As temperatures began to rise in Nova Scotia, there were less lichen for them to eat.

"We don't have the lichen assemblages, we don't have the old growth forest and of course we're losing a lot of barren areas, so it's changed and they've shifted north," he said.

Despite shedding some light on exactly who is pulling Santa's sleigh, science still hasn't figured out the big question — what makes reindeer fly?

With files from Mainstreet