Making a Point

Some of our favorite mammals are adorned with horns

True horns are permanent, paired protuberances that are tough, strong, and durable. Thick layers of a fibrous protein called keratin surround a horn’s bony core. In some species, both males and females have horns. In others, only males have them.

BY Donna Parham

Photography by Ken Bohn

Photos: (Jackson’s chameleon) Hawaiian/iStock/Getty Images Plus; (Markhor) HeitiPaves/Getty Images Plus.