The bighorn sheep’s spiraling helmet is an iconic example of horns. Horns are rigid, curving structures growing from an animal’s head. While bovines are the only creatures sporting true horns, other animals, like rhinos, giraffes, pronghorns and even deer, have horn-like structures.
The only true horns in the animal kingdom belong to members of the family Bovidae, which includes cows, sheep, goats and antelopes. Horns protrude from the skull, and are comprised of a bony core sheathed in keratin, the same material that makes up our fingernails. While they curve, curl, or spiral, horns never branch. They never shed or stop growing. Horns are present on males of all species of bovine, and usually are present on the females as well.
While the rhino is well-known for his horned nose, this isn’t the same as a bovine horn. Rhino horns lack the bony core of true horns. Instead, they are made completely of keratin. They do contain calcium and melanin, which add strength and protect the horn from the sun’s UV rays. Rhino horns are similar to hooves and bird beaks.
Giraffe horns, called ossicones, share many characteristics with bovine horns. They are permanent, paired and don’t branch. However, they are covered in skin and hair. Male and female giraffes have horns present from birth. Like most horned creatures, male giraffes will use their horns when sparring with other males.
While called pronghorn antelopes, pronghorns don’t belong to the bovidae family as antelopes do. Pronghorns are the only members of their own family, Antilocapridae. Pronghorn horns are kind of like a mix of true horns and antlers. Their horns branch, having two prongs. They also have bony cores and keratin sheaths, like bovine horns, but they shed them annually, similar to antlers.
While antlers technically aren’t horns, they are similar in many respects. Antlers are characteristic to members of the family Cervidae, or deer family. They grow from a deer’s head, and males use them when sparring with other males. However, unlike horns, antlers are present only in males in most species. Antlers are made only of bone, not keratin. Deer shed their antlers every year, growing a brand new set every mating season.
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