Credit: Kyle Hutchison Diversity in diet plays a role in the complexity of venom in pit vipers such as rattlesnakes, copperheads and cottonmouths. But new collaborative research by Clemson University scientists found the number of prey species a snake ate did not drive venom complexity. Rather, it was how far apart the prey species were from each other evolutionarily. "It's not just diet that drives the variation in venom across snakes. It's the breadth of diet," said Christopher Parkinson, a professor in the College of Science's Department of Biological Sciences. "If a snake eats 20 different species of mammals, its venom will not be very complex. But if it eats a centipede, a frog, a bird and a mammal, it's going to have a highly complex venom because each component of that venom is affecting something different in one of the different animals the snake is feeding upon."