The United States is home to 15 species of rattlesnake, including the western diamondback and sidewinder, according to the Internet Center for Wildlife Damage Management. Rattlesnakes are one of four venomous snakes found in the U.S. and are members of the pit viper family -- that means they have lateral pits to serve as heat sensors.
Rattlesnakes exist in a range of colors, depending on the species. Some colors include brown, grey and rust. Different species also have varying patterns, such as bands and diamonds.
The rattle is the distinguishing feature of rattlesnakes. They use it as a warning system before striking. The sound is made by the rattle segments, or buttons, bumping into each other as the snake moves its tail. A new button is produced each time the snake sheds its skin. Buttons can easily fall off, however, so counting rattle segments will not reveal a snake's age.
Rattlesnakes have forked tongues that they use to collect information about the environment. The tongue gathers particles from the environment and then places them on Jacobson's organ, located on the roof of the mouth. This allows the snake to identify prey, predators, mates and other objects.
Rattlesnake venom is made up of enzymes that paralyze prey and destroy blood cells. Venom is injected into prey through the snakes' fangs, which act like hypodermic needles. When at rest, the fangs fold back to rest against the top of a snake's mouth. When the snake moves to strike, the fangs move forward and the jaw opens up to 180 degrees. While rattlesnakes cannot spit venom, venom may squirt out of the fangs if enough pressure is placed on the roof of the mouth, where venom glands are located.
The head of a rattlesnake is triangular. Its eyes feature vertical pupils, similar to a cat's. Rattlesnakes have excellent vision. The loreal pits are visible holes located between the snake's eyes and nostrils. These pits sense heat and create a heat image that allows the snake to accurately locate prey even in total darkness. Rattlesnakes can smell through their nostrils, although they use their other senses to a greater degree. Nostrils are mainly used for breathing. Finally, rattlesnakes pick up vibrations through contact with the ground. These vibrations are transmitted to the inner ear, which allows the snake to hear. Rattlesnakes do not have an outer ear to pick up sound waves from the air.
Females produce eggs that, once fertilized, grow and hatch within the snake. The mother snake usually gives birth to 5 to 12 snakes. Rattlesnakes are fully functional when born and have a single-button rattle, fangs and venom.
Maureen Malone started writing in 2008. She writes articles for business promotion and informational articles on various websites. Malone has a Bachelor of Science in technical management with an emphasis in biology from DeVry University.