Believe it or not, both male and female reindeer grow antlers, and despite the depiction of Dasher, Dancer, Prancer, Vixen, Comet, Cupid, Donner, Blitzen, (and Rudolph) as males in most media; they are most likely females.
Though the shedding schedule of a deer’s antlers can be affected by climate and age, most male reindeer lose their horns in the Winter, which, incidentally, is when Christmas occurs.
Females lose their antlers during the warm summer months, while males keep theirs to fight for breeding rights. By the time winter rolls around, male reindeer aren’t just without their horns, but are also usually much less nourished and fattened than the females. Not only would Santa’s reindeer have to be female to have horns, but to be big and strong enough to pull a sleigh full of toys, they’d have to be in peak physical condition.
Referring back to reindeer names, the original Dutch reindeer lore has deer named Dunder and Blixem, meaning thunder and lightning, instead of Donner and Blitzen. Rudolph may have been a late addition to Santa’s squad, but red-nosed reindeer to crop up in the wild.
Because reindeer live in the harshest of wintery tundras, they must migrate under sub-zero conditions. To aid them in supporting their powerful bodies, they have dense arrays of capillaries in their noses, which sometimes appear pink. This warm flow of blood warms the air they breathe in, keeping them from getting brain freezes while running.
As for being able to see in blizzard conditions, reindeer have special eyes to aid them through the virtually sunless days of the Arctic. Reindeer have the ability to see ultraviolet light and are unaffected by snow-blindness. They can easily see a predator’s urine in the snow, spot other reindeer through storms, and even see food below the ice. They also have a reflective coating behind their eyes that helps bounce more light into their retinas, enhancing their night vision!