Rudolph the reindeer really has a red nose - scientists
The story of Rudolph the red-nosed reindeer may be based on scientific fact, according to the findings from a new study.
Researchers in Sweden have used thermal imaging cameras to capture the heat coming from reindeer as they graze.
They found that while most of the animals are well insulated by their fur, their noses glow bright orange in the images due to the large amounts of heat they release.
This is because reindeer have a high concentration of blood vessels in their nose and lips to help keep them warm and sensitive when rummaging through snow as they search for food.
Professor Ronald Kröger, a zoologist at Lund University in Sweden, said that in some cases these even led to the animals mule, or snout, taking on a reddish colour in cold weather.
He said: “When reindeer are feeding, their mules are exposed to very low temperatures as they look for food under the snow. They need to maintain sensitivity in order to know what they’re actually eating.
"They pump warm blood into the mule which means it can be a bit reddish because of this strong blood flow.
"The thermographic cameras show the heat coming from their body. The eyes and the mule are lighter and warmer than the rest of the body."
The story of Rudolph and his red nose dates back to a book written in 1939 by Robert L May and has subsequently featured in hundreds of stories, songs and films about the folklore of Father Christmas and his sleigh.
They found that the reindeer's noses glow bright orange when viewed with infrared light. This is because they have 25 per cent more blood vessels there compared to human noses.
Professor Kröger has been using thermal cameras to study the body heat given off by animals in an attempt to understand their physiology in ways not visible to the human eye.
He said: “Dogs are the exact opposite to reindeer. Nobody knows why their noses are cold and why they have evolved that way. That is what we want to find out.”