WHY IS RUDOLPH'S NOSE RED????

   Why is Rudolph's nose red???
    It's no wonder Rudolph the red-nosed reindeer is the most famous member of Santa's team...on top of being a skilled flyer, his nose, as his name suggests, glows bright red.  This unusual variation on the reindeer nasal prominence could have all kinds of benefits, the most important of which would involve guiding Santa's sleigh.
   According to folklore, if the weather's ever bad on Christmas Eve, Santa's cleared for flight by the FAA, for that matter...thanks to the brightness of Rudolph's nose.
   But how does Rudolph's nose actually work?  How could one reindeer create a light bright enough to lead a sleigh through darkness and inclement weather?  And how could a reindeer actually develop a red nose?
   Although no one may ever know for sure just how Rudolph got his unusual nose, I have what could be the most logical explanation for how the doe-eyed deer guides Santa's sleigh: science.

Rudolph's Bioluminescence

  Rudolph could use something many organisms use on Earth in order to create natural light...a neat little scientific trick call bioluminescence.  Animals can make their own light by mixing certain chemical compounds together to produce a glow.  The reasons vary...fireflies, for instance, flash light at each other in order to attract mates, while some fish that live very deep in the ocean use light to locate prey.
   There would be three parts to his nasal beacon.  The first would be just like any other reindeer nose (so playmates technically shouldn't have shunned him from any reindeer games in the first place).  He would breathe oxygen through it, and it would be 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.  The other two parts, however, would set Rudolph apart from all the other reindeer.
   The second part is a thin, enclosed layer of a light-producing organ between the dermis and epidermis.  Inside this layer is luciferin, a light-producing substance, and luciferase, an enzyme that catalyzes the light-producing reaction.

   The third part is where the "red nosed reindeer" part comes in.  Most bioluminecent life forms, like fireflies, produce green light.  The outermost part of Rudolph's nose, however, would be a red phosphorescent layer...once the light-producing organs, providing enough reactions for long, intensely shiny bursts of light.
   But why is Rudolph the only reindeer with a nose that glows?

Rudolph and Evolution

   So we know that Rudolph stands out a bit from other reindeer, but how could something like this have happened??...Could Santa be some kind of a mad scientist, tweaking reindeer DNA for his own benefit, or could Rudolph's nose be a biological accident?
   It's possible that Rudolph's bright honker could be a reindeer atavism, But what's an atavism???
   An atavism is a trait of distant ancestors that randomly pops up in modern-day organisms...a whale with legs or a human with a tail are two examples.  These traits may have served a purpose for the animal way back when, but for whatever reason the trait was "silenced" over time, every once in awhile making a rare triumphant return in modern times.  Could distant reindeer ancestors of Rudolph have needed to produce light in order to survive in the wild?  You'll find most reindeer in Scandinavia, and it does get pretty dark there during the winter...so could Rudolph's ancestors have needed a better way to get around at night?

   But that doesn't explain why only Rudolph has a bioluminescent nose.  When we look closer at Rudolph's childhood, however, it could be that his bright nose was a rapid evolutionary adaptation.  It's possible that the real reason Rudolph couldn't play in all those reindeer games was due to his poor eyesight...he developed the red nose in order to compensate, and it just happened to save Christmas when Santa really needed it.
   Although his playmates treated him like a misfit in the beginning, Rudolph actually proved himself to be the stronger specimen.  Determined to excel, he could have adapted out of necessity.  The question now is whether or not future generations of reindeer could also take on Rudolph's unique traits.