A brainless slime mould redesigned the Tokyo rail network.

In 2010, researchers placed oat flakes on a map in the positions of cities around Tokyo, with a slime mould at the centre. It spread out, then pruned itself into a network of tubes strikingly similar to the real railway.

Truth label: Established. Strong evidence and broad agreement among experts.

Go deeper

No brain needed

The slime mould is a single giant cell. It strengthens tubes that carry food well and lets others fade.

Maze solver

It can also find the shortest route through a maze to reach food.

Learn

1. Learning from it. Engineers study its simple rules to design efficient, resilient networks.

Test yourself

Sources

• Physarum polycephalum

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