Even though no one has actually seen a reindeer fly, this special member of the deer family has a lot to live up to! Reindeer and caribou are classified as the same genus and species—Rangifer tarandus—but caribou are slightly larger, and reindeer are domesticated. “Reindeer” is the European and Asian name for the animal that is used by humans to pull sleds or carry packs, and “caribou” is the name used in the northern parts of North America. Those of us in the United States use “reindeer” when referring to the domesticated animal. Antlers are the most memorable characteristic of reindeer.But what are the antlers for? They are handy weapons against predators, and males use their impressive antlers (which can weigh up to 33 pounds, or 15 kilograms!) to impress the females.Reindeer love a good crowd. A social species, they form large regional herds of 50,000 to 500,000 animals during the spring. The herds generally follow food sources, traveling south (up to 1,000 miles, or 1,600 kilometers) when food is hard to find in winter. Reindeer are ruminants. When available, they eat mosses, herbs, ferns, grasses, and shoots and leaves of shrubs and trees, especially willow and birch. In winter, they make do with lichen and fungi, scraping the snow away with their hooves. The reindeer is thought to have first been domesticated by humans at least 3,000 years ago (and perhaps as long as 7,000 years ago) in northern Eurasia ( Lapland) and still remains the only deer species to be widely domesticated. They are used as beasts of burden and farmed for milk, meat, and their hides. Currently, there has been concern about how herds will be affected by companies drilling for oil and gas lines, as these activities often block the reindeer’s travel routes.