Read a rather fascinating article ”Slime Mold Grows Network Just Like Tokyo Rail System” in which scientists have drawn parallels with the Tokyo railway network is laid out and the way slime mold (Physarum polycephalum) forms nutrient tunnels between food sources.

The research intially seems to have been directed at analysing the efficiency of the nework layout for the Tokyo rail system, and surprisingly it appears to be fairly effective. Of course, the slime mold network didn’t have to worry about little things like planning permission or how long it would take to drill through a particular mountain. Of course, the rail network has probably evolved in its design over many years - I don’t think the original designers would have gotten it right first time, this means that the population growth and population centres/distribution would have affected the design decisions over the years. That said, it is interesting nonetheless.

Interestingly in an article for the New York Times: ”The Wisdom of Slime” a map of the major US highways is reproduced by the same species.

This kind of things is all very well and good, but do we really need to validate our transport infrastructure? No, not really, but luckily there are some other more realistic uses for the slime. In a paper from 2008 entitled “A mathematical model for adaptive transport network in path finding by true slime mold” a mathematical model of the slime mold is used to solve mazes. This work has been enhanced to provide evidence for biological computing: using the slime as a kind of logic gate. Fascinating.

References

• Physarum Machines
• Slime mould logical gates: exploring ballistic approach
• Steering plasmodium with light: Dynamical programming of Physarum machine