Pumpkin toadlets, also called Brachycephalus frogs, live in southern Brazil. Although they can jump in the air, they roll, cartwheel or backflip, and then plummet to the ground. They often end up belly-flopping or crash-landing on their backs.

Richard Essner, Jr., a zoologist, says, “I’ve looked at many frogs, and these are the weirdest things I’ve ever seen. He works with vertebrates at Southern Illinois University Edwardsville.

Essner and his colleagues have discovered these animals’ lack of internal equipment needed to sense changes in rotation. Most of the time, fluid sloshing through the bony tubes in an animal’s inner ear helps it feel its body’s position. However, the pumpkin toadlet’s tubes are so small that their tiny tubes don’t work.

Essner observed that these animals might just stay grounded and crawl exceptionally slowly.