What’s the Difference Between Antlers and Horns?
By Marilyn Shy, Kalkaska Conservation District
The words “antlers” and “horns” on deer and other animals are often used interchangeably. But there are distinct differences. Horns are not just antlers on a different animal, or vice versa. However, there are many similarities between the two.
A common mistake that people make is assuming deer have horns. Along with moose and elk, deer are members of the Cervidae family, which is the only class of mammals that grows antlers. These are grown every spring and shed every winter. At the root of each antler is a small, bony growth called a pedicel. Antlers are made of bone and initially covered with “velvet”, a kind of skin tissue that carries blood and nutrients during development. When the antlers are done growing, the velvet dies. The animals shed this layer by scraping its antlers on brush and trees. When this process is going on, the antlers look sort of raggedy, with some of the shredded velvet hanging loosely from the emerging antlers.
In the winter, when the growth hormones stop pumping, the pedicel loses calcium, which weakens the connection between it and the antler. At this point, the antlers fall off. Since they are made of bone, they persist in the environment and you can sometimes find them laying on the ground. You may have heard people call these “sheds.”
Antlers are grown exclusively by males, except in reindeer (also called caribou). They are primarily used in clashes by males competing with one another for mates.
By comparison, horns are attached permanently to the animals who have them. They do not regrow each year. Horns are found on members of the Bovidae family, which includes cows, sheep, goats, water buffalo, antelopes and gazelles. Horns can appear on both males and females depending on the species. The size and shape of horns can vary quite a bit from one animal to the next. Just think of the long, curved horns of the mountain goat, compared to the shorter, more compact horn of the American bison.
Unlike antlers, horns are never branched or shed. In many species, they never stop growing throughout an animal’s life. The only scenario in which a bovid loses its horns is if they are broken off. The continuous growth of their horns is important since they become worn with use.
Horns have a core of bone, but unlike antlers, they are covered with keratin, the same substance that makes up he human fingernail. Similar to cervids, bovid males use horns in fights and displays of strength during the mating season. In species where females have horns, they’re usually smaller and used more as a defensive tool than an offensive weapon.
One unique animal that has horns is the Pronghorn Antelope. Its horns are actually a cross between horns and antlers, with characteristics of both. True horns have only one point, not the prongs or forks that antlers have. Yet the male pronghorn can grow horns 10 inches in length with a forward-facing prong. Like the Bovidae, the sheath of the horn is made of keratin, but unlike the other animals that sport horns, the pronghorn shed its horns each year. Although the pronghorn looks like many antelopes, it is different enough to have its own taxonomic family, the Antilocapridae.
One of the yaks from the ranch near Kalkaska. Photo credit: A Yak or 2 Ranch - Nathan Priest
So what about giraffes? Don’t they have horns? Well, yes, they do, but they have a special name due to their composition. The giraffe’s horns are called ossicones which are actually cartilage hardened into bone (ossified cartilage covered in skin). Both female and male giraffes have ossicones. The ossicones are present right from birth, making it the only mammal to have horns when they are just born. In females, the ossicones are relatively thin and hairy, but in male giraffes, the ossicones are thick, and the tops are bald due to fights between them.
To see some local horns up close, A Yak or 2 Ranch in Kalkaska County near Mancelona has a herd of yaks displaying horns on the shaggy Bovidae.