Western diamondback rattlesnakes have heat sensitive pits for locating prey and hemotoxic venom to incapacitate small animals. These snakes are excellent at conserving energy and can survive nearly two years without food.
The Western diamondback rattlesnake is a large, heavy pit viper native to the Southwestern United States and Mexico. One of the most important adaptations of the Western diamondback, as with all pit vipers, is the heat-sensitive pit between the eyes and nostrils. The pit is sensitive to infrared energy given off by the snake's mammalian prey. A membrane divides the pit into two unequal sections, allowing the snake to better pinpoint the location of prey. A rattlesnake incapable of seeing or smelling is still able to locate prey using its pits, providing the animal is slightly warmer than ambient air temperature.
Venom is another important adaptation for the Western diamondback. A diamondback relies on venom to subdue prey that might otherwise harm it. Western diamondback venom contains a hemotoxin that attacks red blood cells, impacting the heart and blood vessels. Other venom components attack skeletal and heart muscle, leading to a decrease in mobility and, eventually, heart failure.
Western diamondback rattlesnakes inhabit hot, arid climates. During an especially dry season, food becomes scarce, requiring the snakes to conserve resources. Western diamondbacks can survive on fat stores up to two years, if necessary.