Physarum polycephalum, an amoeboid slide mold, is a single-celled organism that can form plasmodium (multinucleate masses of protoplasm, also called protoplasmic veins), that spreads through cytoplasmic streaming. The interesting thing about the mold is its logical way of distributing the veins. The organism hates light and spreads towards food.
Dr. Andrew Adamatzky from University of the West of England Bristol just published a paper in arXiv that outlines a general way of constructing a biological computer that can take advantage of this organism’s behavior.
The Physics arXiv Blog explains:
Physarum polycephalum has a complex lifestyle but in one phase of its existence it forms a single-celled creature called a plasmodium that is visible to the naked eye. When this creature forages for food, it physically surrounds whatever it has settled on for lunch, secretes a few enzymes and digests it. If it finds several food sources, it sends out numerous tubes that form a kind of digestive network. It is this network that can find its way efficiently through a maze (provided there is food in the middle).
Here’s how it works. You “program” this biocomputer by creating a pattern of lights and oak flakes that make a kind of obstacle course for the plasmodium to negotiate. You then “run” the program by allowing the creature to tackle this obstacle course and you read out the result by examining the shape of the network that the plasmodium forms.
More from the Physics arXiv Blog…
Image: Protoplasmic network shaped by light obstacles.
Full article from arXiv: Steering plasmodium with light: Dynamical programming of Physarum machine (.pdf)