Merry Christmas! Today’s IFOD contains a Reindeer joke and then a few interesting facts about Reindeer.
The joke, courtesy of the flight attendant on my Southwest flight last week:
“Which of Santa’s reindeer is a dinosaur’s least favorite?”
Scroll down for answer
Wait for it . . .
- Reindeer can see in the ultraviolet spectrum which helps them to see in the arctic. Snow covered ground reflects about 90% of the UV light that hits it whereas non-snow covered land only reflects a few percent. So, being able to see UV light is a big advantage in foraging for food and avoiding predators. And seeing where to land on snow-covered roofs on Christmas Eve. They are thought to be the only mammals who can see ultraviolet light.
- Reindeer and caribou (considered the same species) are the only deer where the males, females and calves all grow antlers.
- Santa’s reindeer are depicted with antlers, which means despite their masculine names, they are likely female. Male reindeer shed their antlers by early December each year, which is the end of mating season. While it is possible that a male reindeer here or there may have retained their antlers as late as Christmas, it wouldn’t be all of them each and every year. It is possible that Santa castrated his reindeer which could explain his reindeer’s antlers in late December (castrated male deer are known as “steers”). Thanks to Audrey Jennings for this fact.
- Antlers are actually quite impractical. They are used for social dominance (like beards). Related, the costly signaling theory: http://www.theifod.com/altruism-and-peacocks/
- Reindeer hooves expand in summer when the ground is soft and shrink in winter when the ground is hard.
- Some subspecies have knees that make a clicking noise when they walk so the animals can stay together in a blizzard.