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Yellowstone National ParkA Grizzly Bear sow keeps careful watch over her two cubs.
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Yellowstone National Park
Difference Between Antlers and Horns

Antlers, on members of the deer family, are grown as an extension of the animal's skull. They are true bone and are a single structure They are generally found only on males. Antlers are shed and regrown each year.

Horns, found on pronghorn, bighorn sheep, bison, and many other bovine, are two-part structures. An interior of bone (also an extension of the skull) is covered by an exterior sheath grown by specialized hair follicles, as are your fingernails. In fact, your fingernails and the exterior sheath of horns are made of very similar materials. Horns are never shed and continue to grow throughout the animals life. The exception to this rule is the pronghorn which sheds and regrows its horn sheath each year. 

To figure out who the antlers & horns in the photo belong to, go back to the Antler Horn Match Games by clicking "Back to the Game" below. 

Why you should leave them on the ground

Back to the Game

Lake Trout Illustration  

Did You Know?
Lake trout are an invasive species of fish that is decimating the native cutthroat trout population in Yellowstone Lake.

Last Updated: July 17, 2007 at 12:12 EST