Why does Rudolph have a red nose?

Hello, Santamory here! You know, the one in charge of all the science and technology here at the North Pole.

Now, as you all know, Rudolph is the most famous member of Santa’s team. As well as being a skilled flyer, his nose glows bright red. This unusual variation on the reindeer nasal prominence has all kinds of benefits – the most important of which is helping guide Santa’s sleigh.

But you may be wondering why does Rudolph’s nose shine so bright.

Well, many organisms on Earth use a neat little scientific trick called bioluminescence to create light. Sea creatures at the bottom of the oceans can make light by mixing certain chemical compounds together to produce a glow to help locate prey, whilst fireflies flash light at each other in order to attract mates.

Now Santa doesn’t need to deliver presents at the bottom of the ocean, so that isn’t quite how Rudolph’s nose works. All reindeers have many more blood vessels in their noses than humans have. This helps them to breathe in the extreme cold of the North Pole. If you saw a reindeer under a special UV light, then ALL of their noses would look pretty red. So really there was no need for any of the other reindeer to shun Rudolph or exclude him from any reindeer games.

Just like every other reindeer, Rudolph breathes oxygen through his nose, which is made up of two layers – the dermis (the thick, inner layer of skin that contains blood vessels and hair follicles) and the epidermis (the thin, outer layer that you can see and touch).

So despite all these similarities, we know that Rudolph stands out a bit from other reindeer. But how could something like this have happened? Well, I can’t give away all the secrets – some say that the elves and Santa are tweaking reindeer DNA for their own benefit, whilst others say that Rudolph’s nose is a biological accident – an ATAVISM – that’s a trait from a distant evolutionary ancestor that reappears in a modern-day organism. Perhaps once there were herds of red nosed reindeers at the North Pole. Can you imagine that!

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