In our cultural ethos, rattlesnakes are inextricably linked with the wild west of tumbleweeds, cowboys, horses, sheriffs, and outlaws. These reptiles are indigenous to the Americas and have several notable features. The most distinctive is the rattle at the tip of their tails which they can move 60 or more times per second producing a sound which serves as a warning of their proximity. Rattlesnakes are deaf, but they compensate for this by having a highly developed sense of smell. In fact, the reason why rattlesnakes (and other snakes) constantly stick their tongues in and out of their mouths is to bring scent particles in contact with their smell organs which lie in the roof of the mouth.
Rattlesnakes do not hear sound, rather they have an inner ear that is very sensitive to vibrations in the ground which are transmitted to it by the snake’s muscles and jaw bones. Besides also having very good vision, rattlesnakes have the ability to sense heat thanks to organs located behind each nostril which gives the snakes the ability of heat vision allowing them to hunt in the dark. Rattlesnakes have a venom which they inject through their fangs when they bite much in the same way that a hypodermic needle works. The venom consists of proteins that break down cells and tissues, as well as anticoagulants and neurotoxins that cause circulatory arrest and respiratory paralysis.
The Timber Rattlesnake (Crotalus horridus) featured in the video below was filmed at the Zoo Knoxville in Knoxville, Tennessee.