Now, researchers have found for the mouse, the sting really is nothing. Instead of causing pain, the scorpion venom blocks it, a fact that could lead to the development of new pain-blocking drugs for people.
“The venom actually blocks the pain signal that the venom is trying to send” to the mouse, said study researcher Ashlee Rowe of Michigan State University. “We don’t want to try to sound too cute or anything, but it is sort of like an evolutionary martial art, where the grasshopper mice are turning the tables. They’re using their opponents’ strength against them.”
Southern grasshopper mice (Onychomys torridus) are carnivorous desert-dwellers. Among their favorite meals are the Arizona bark scorpions (Centruroides sculpturatus). The scorpions’ sting would kill any other rodent the size of the grasshopper mouse, but the little rodent can absorb many stings in the course of attacking a scorpion. In studying this phenomenon, Rowe noticed not only did the mice survive, but they also seemed unconcerned.