The rhinoceros cuts an imposing figure with its one or two horns, thick gray skin and weight in excess of a ton. Still, the six species that comprise this family of odd-toed ungulates lack front teeth and use their lips to tear at tasty grasses and leaves. Relentlessly hunted near the point of extinction for its prized horn, the only true predator of the rhino is mankind, although it may have to fight off a wildcat now and again. Nature has given the rhino some ways in which to protect himself.
The black rhino, white rhino, Nile rhino and Sumatran rhino each have two horns on the bridge of the nose, the larger one closer to the nostrils. The Indian rhino and Javan rhino each have one horn. A black rhino's nasal horn can be up to three feet in length. These horns are actually keratin, the same as hair and fingernails, but are in demand by poachers for traditional Asian medicine and to make trinkets such as dagger handles. The rhino uses this horn to ward off lions and in spats with other rhinos.
Rhinos have a reputation for being easily irked, particularly the solitary black rhino. A rhino will charge at speeds up to 30 miles per hour, head down and ready to gore with its horns, when he feels provoked to attack. The charge demonstrates remarkable agility for this bulky creature.
Rhinos have very poor eyesight but have heightened senses of hearing and smell to know when danger is coming. Black rhinos have long tube-shaped ears that can swivel to pick up noises from any direction and from great distances. To communicate, they speak a series of growls, grunts, squeaks, snorts and bellows.
A rhino can get a layer of bug defense with a nice wallow in the mud, but it gets an extra hand defending its skin against pests with the help of "tick birds." The sub-Saharan oxpeckers eat ticks, flies, fleas and lice, and also help remove earwax and grease from the rhino's body. The birds will also stir up an alarm and react noisily if danger is on the horizon; on wildlife preserves, this cry also alerts wardens that poachers may be near. Rhinos tolerate their perched friends well despite the fact that oxpeckers also pick at their wounds.