Snakes are specialized animals, having elongated bodies and no legs. They have no ears, externally or internally, and no eyelids, except for a protective window beneath which the eye moves. The organs of the body are elongated. Snakes have a long, forked tongue, which helps them smell. Gaseous particles from odors are picked up by the tongue and inserted into the two-holed organ, called the Jacobson’s Organ, at the roof of the mouth.

The two halves of the lower jaw are not fused, but are connected by a ligament to each other. They are also loosely connected so the snake can swallow food much larger than its head. Because snakes are cold-blooded and not very active, one meal may last them several weeks. Also, because they are cold-blooded, they may hibernate during cold weather months or aestivate during hot summer months when the climate is severe. In either case, they consume little or no food during these times. Some snakes lay eggs, some hatch their eggs inside the body, and some give live birth. The young of copperheads, rattlesnakes, and cottonmouths are born alive.

Nonpoisonous snakes are harmless to humans. In most cases, a snake will crawl away when approached if it feels it can reach cover safely. No snakes charge or attack people, with the exception of the racers, which occasionally bluff by advancing towards an intruder. Racers will retreat rapidly, however, if challenged. Snakes react only when cornered. Different species react in different ways, playing dead by turning over on their back, hissing, opening the mouth in a menacing manner, coiling, and striking and biting if necessary.

A nonpoisonous snake bite has no venom and can do no more harm than frighten the victim. After being bitten several thousand times by nonpoisonous snakes, the author and his students have never suffered any adverse reaction, and no treatment was ever used. The only harm nonpoisonous snakes can cause is frightening people who are not familiar with them. A bit from a poisonous snake, however, causes an almost immediate reaction--swelling, tissue turning a dark blue-black, a tingling sensation, and nausea. If none of these is observed or felt, the bite was from a nonpoisonous snake. Also, bites from one of the pit vipers (copperheads, rattlesnakes, and cottonmouths) will reveal two fang marks, in addition to teeth marks. All snakes have teeth; only pit vipers have fangs. North American pit vipers have only two rows of teeth on top and bottom. whereas nonpoisonous snakes have four on top and four on the bottom.