Rattle Snakes

Rattlesnakes are a group of venomous snake, genera crotalus and sistrirus. They belong to the subfamily of venomous snakes known as Crotaliane (pit vipers).

There are approximately thirty species of rattle snake, with numerous subspecies. They receive their name for the rattle located at the end of their tails. The rattle is used as a warning device when threatened. The scientific name Crotalus derives from the Greek, κρόταλον, meaning "castanet". The name Sistrurus is the Latinized form of the Greek word for "tail rattler" (Σείστρουρος, Seistrouros) and shares its root with the ancient Egyptian musical instrument, the sistrum, a type of rattle. Most rattlesnakes mate in the spring. All species give live birth, rather than laying eggs. The young are self-sufficient from birth. Since they do not need their mother after birth, the mother does not remain with her young. However, at least one captive study has demonstrated that females and their neonates show some level of affinity for each other's company and will cross barriers to reunite if separated.

Contrary to popular myth, rattlesnakes are not deaf. In fact, the structure of their inner ears is very much like that of other reptiles. They do, however, lack external ears. Sound (whether from air or ground vibration) is transmitted to the snake's inner ear via vibrations in other body structures.

Rattlesnakes are native to the Americas, with the large majority of species in the American southwest and Mexico. The state of Arizona in particular has more species than any other state. Four species may be found east of the Mississipi river, and only 2 in South America.