We all know that reindeer pull Santa’s sleigh, and that they can fly. We know that this is a myth because we know that deer do not fly. But how do we know what a ‘deer’ actually is, and how do we know that it is not a member of the group of creatures that can fly? How do we sort animals into groups, and what do those groups tell us about the animals in them?

Reindeer illustrate one of the most interesting problems in zoology, which is that of common names vs. Latin names. Reindeer are known by different common names depending on where they are, even though they are all the same species. A reindeer and a caribou, for instance, are in fact the same animal. In some places, what we know as elk are also reindeer, but in other places, an elk is the same thing as a moose, which is definitely not the same thing as a reindeer.

The Latin naming and categorizing system (known as taxonomy) that we use for animals was invented in the late 1700’s by Carl Linnaeus, and is known formally as the Linnaean system. While it has been modified and changed over the years, and continues to be so, it remains the same basic system , which indicates how incredibly effective it is. The Linnaean system divides animals into ever-more-specific categories, based on the animals’ basic features. It starts with an assignment into the broadest possible category – is it an animal or a plant? This category is called the Kingdom. It has four parts: Animalia, Monera, Protista, and Metaphyta. Of these, three are plant or plant-like creatures. Animalia, of course, is animals. After Kingdom comes Phylum, which further breaks down Animalia into categories based on basic characteristics such as: does it have a spinal cord or not? The next category is Class – this is the category where it becomes specific enough to start the real differentiation between types of animals.

The Classes are probably familiar to us all, although in non-Latin terms. They are: Pisces (fish), Amphibia (amphibians such as frogs), Reptilia (reptiles, such as snakes), Aves (birds), and Mammalia (mammals such as humans). These are the basic divisions by which people generally identify animals. But think of what is was like before Linnaeus! These basic divisions did not exist yet, so we did not have the tools to describe animals ard put them into categories that made sense. Add to that the confusion between names – sometimes several explorers would ‘discover’ exactly the same species, and each would give it its own name – and it’s surprising that natural history was explicable at all.

After Class comes Order. This is where things get a little complicated, as scientists are still trying to figure out what Order certain animals belong to. In the beginning, imagine what could be done with the platypus. It didn’t fit the description for Class Mammalia, because it laid eggs. But it had fur and nursed its young, which made it ineligible for Class Reptilia or Amphibia. And it surely was not a bird or a fish. But by dividing Classes into Orders, the platypus had a place. It was given its own Order, within the Mammalia Class, which allowed for it to have an overall classification that made sense, given its many mammal-like characteristics, but which also allowed, at the Order level, for its idiosyncracies to be noted.

So let’s look at our reindeer friend. Reindeer are, of course, animals. They have spinal cords. They are mammals. So what Order are they? Reindeer belong to the Order Artiodactyla. An Artiodactyl is an even-toed ungulate. “Ungulate” means that it is vegetarian, grazing animal (like deer, sheep, goats, etc.). Even-toed means that it has an even number of toes (or hooves.) The other Order of ungulates is Perissodactlya, which is odd-toed ungulates, such as the horse – and, interestingly, the rhino.

Reindeer, then, are grouped with other animals that eat plants and have an even number of toes. This is a very large Order, including everything from reindeer to pigs to hippos. But the very beauty of it is in its flexibility. Who knew, when hippos were first discovered and named, that they were largely peaceful, grass-eating creatures? With their huge imposing teeth, perhaps they were first classified as meat-eaters (Order Carnivora) before it was realized where they belonged and they could be moved to the ungulates. Then someone had to be brave enough to get close enough to count the toes! And who would have thought, without this classification system in place, that the enormous water-dwelling hippo was related to the delicate little chevrotain, a tiny mouse-like deer? And yet, there it is, and recently supported by DNA testing as well – the chevrotain, the goats, the sheep, the deer – all related and all related to the hippo.

But back to our reindeer/caribou/elk. After Order comes Family. This is where the large Orders start getting divided into recognizable groups. The Artiodactyls get divided into deer, goats, pigs, camels, and so on. We can all usually recognize the differences between these animals when we see them. We know the difference between a pig and a goat, or a deer and a giraffe. This is the group we are most likely to use when trying to describe an animal to someone: we say “it’s a kind of goat” or “it’s like a deer.” This is also where the standard naming system begins to be used commonly. A standard Latin name for an animal starts with the Family – classifications before that can be inferred or are simply not needed to identify the animal. After Family comes the Genus and the Species. These two categories, along with Family, provide the basic Latin name of an animal. Genus is a division that breaks Family down based on detailed characteristics, and Species is usually the final designation. (There are subspecies, but the specifics of how they are identified and named is constantly evolving, and very complex.)

The reindeer, then, is scientifically known as Cervidae Rangifer tarandus. The way this would usually be written is C. Rangifer tarandus. Cervidae, the Family, includes all the deer and deer-like creatures with even numbers of toes (and excludes the other Artiodactyls, like pigs). Rangifer, the Genus, includes all species and subspecies of reindeer (sometimes the Genus includes different species, in this case it includes only the reindeer) and finally tarandus. I have been unable to find the Latin translation of either Rangifer or tarandus – perhaps someone could help me out over in the Forums?

In closing, Happy Holidays to you all, and may Santa and his team of C. Rangifer tarandus visit your home this year!