Brainless Slime Mold Naturally Recreates Tokyo Rail System Design

Humans tend to think of themselves as smart, but it turns out a slime mold—with nothing even similar to a brain—can do just as good a job as some of the brightest engineers. At least that’s what researchers are hinting at, since they’ve shown that a slime mold mapped out the basic shape of the Tokyo metro system in less than two days.

Researchers placed small amounts of oat flakes over a map of Japan, corresponding to city centers. The slime mold soon found the best way to connect to each of them so it could eat the oat flakes. Previously, researchers have used the mold to find the shortest way to get through a maze.