It turns out that grasshopper mice (Onychomys torridus) are resistant to the painful, and potentially lethal, stings of one of their menu items—the Arizona bark scorpion (Centruroides sculpturatus).

These rodents may be small—ranging from 1.5 to 2 ounces (40 to 60 grams) in weight—but they're carnivorous, "howl" before they kill, and take care of scorpion stings with just a swipe of the tongue to soothe the injured area before eating their prey.

A new study published this week in the journal Science describes just how these curious mice neutralize the pain-producing toxins contained in bark scorpion venom. And it's unlike anything yet discovered in mammals.

The ability to sense pain is important, said study author Ashlee Rowe, an