Saharan desert ants are known to wander great distances in search of food. Twisting and turning on their way, the ants manage to return to their nests along surprisingly direct paths. They sense direction using light from the sky, but how do they judge distance? By counting steps, apparently.
As National Public Radio science correspondent Robert Krulwich explains in this engaging little cartoon, a group of German and Swiss scientists have discovered that by manipulating the stride of the ants halfway through their trip–by either lengthening or shortening their legs–the ants would invariably overshoot or undershoot their return destination. As Princeton biologist James Gould told NPR, “These animals are fooled exactly the way you’d expect if they were counting steps.”