This cute rodent, called a long-eared jerboa, may be tiny, but it’s a contender for one of the biggest records in the animal kingdom: the largest ears relative to body size.

“We don’t know exactly why the long-eared jerboas have such long ears,” says Talia Yuki Moore, a biologist at the University of Michigan. “But studies of other long-eared species suggest that they keep the animals cool.”

Blood vessels near the surface of the rodent’s large ears transfer heat to the air. The adaptation likely helps long-eared jerboas survive in their hot habitat: deserts in Mongolia and China.