Slime has been on earth a lot longer than us – perhaps up to a billion years. Certain types (if you want to be formal, P. Polycephalum) might also be a lot smarter that we thought. Slime can have a sense of time, it can work its way through mazes and – in a recent discovery – it can be used to design efficient railway systems.
The single-celled brainless amoebae did not grow living branches between pieces of food in a random manner; rather, they behaved like a team of human engineers, growing the most efficient networks possible. Just as engineers design railways to get people from one city to another as quickly as possible, given the terrain—only laying down the building materials that are needed—the slime molds hit upon the most economical routes from one morsel to another, conserving energy.
Researchers created a mini petri-dish Japan, with food for all the major cities, and slime-like obstacles where human engineers might find them. In a matter of hours they had recreated something very similar to the complex Japanese railway system.
Andrew Adamatzky of the University of the West of England Bristol and other researchers were so impressed with the protists’ behaviors that they have proposed using slime molds to help plan future roadway construction.