Posted - 04/12/2012 : 7:28:47 PM
| Computers powered by swarms of crabs
by Jacob Aron, "enhanced" by BigDOGGe
Most of us are happy with computers that run on electricity, but imaginative systems based on chemical reactions, slime moulds and a host of other unusual concepts are also capable of computation. Now we've got another to add to the list:
Crabs. The found-in-the-ocean type of crab, not the found-in-my-crotch kind...
It turns out that swarms of soldier crabs herded through tunnels can form the AND, OR and NOT logic gates required to make a computer.
Yukio-Pegio Gunji of Kobe University in Japan and colleagues realized that when two swarms of crabs collide, they merge and continue in a direction that is the sum of their velocities. This behavior means the researchers could adapt a previous model of unconventional computing, based on colliding billiard balls, to work with swarms of crabs, with 0s and 1s represented by the absence or presence of a swarm.
They first tried the idea with simulated crab swarms. The OR gate, which simply combines one or two crab swarms into one, worked every time, but the more complicated AND gate, which involves the combined swarm heading down one of three paths, was less reliable.
They then tried the logic gates for real, using swarms of 40 crabs. The crab swarms were placed at the entrances of the logic gates and encouraged to move by a looming shadow that fooled them into thinking a predatory bird was overhead. The results closely matched the simulation, suggesting that crab-powered computers could indeed be possible.
To be fair, the results were mixed. While Gunji and co found they could build a decent OR gate using soldier crabs, their AND-gate was much less reliable.
However, it's early days and they say it may be possible to produce better results by making conditions inside the computer more crab-friendly. (No crabs were harmed in the making of their computer, say Gunji and co.)
So there you have it--a computer in which the information carriers are swarming balls of soldier crabs.
Not a sentence you expect to read every day. But it surely cannot be long before we all have one of these on our desktops.