Scientists are baffled by the humble slime mold—a brainless, single-cell organism that can solve mazes, learn from experience, and even make decisions.

In one experiment, researchers placed slime molds in a petri dish maze. They quickly found the shortest route to food—without any brain at all.

“They remember. They adapt. It’s like they have a mind,” said Dr. Masanori at Kyoto University.

These fungi-like organisms might hold clues to the origins of intelligence—and could help scientists create smarter robots.

Sometimes, the weirdest life forms are the smartest ones of all.