Bacteriart and Fractal Forms

Eshel Ben-Jacob studies how bacterial communities communicate when faced with a challenge. What odd decisions we would face were we living in these colonies of single-celled foragers:

Larry: The food’s a little scarce over here. It’s getting crowded. Should we turn left? Or branch out forward? I’m not good with directions. Maybe we should ask the group. Or not. All I know is that I’m hungry, and I want to move away from you guys. You’re letting off gross chemicals.

Lisa: There’s some undiscovered country over there, maybe we can branch off of this branch. What’s that? I’m four branches down already? Why is that enormous scientist up there taking a picture of me? And why does he keep saying the word “fractal”?

The intricate patterns created by these microbial colonies are thought to be an emergent property of a brainless system turning simple decisions into very complex ones (which is something that bothers me about Ben-Jacob’s work, since he invokes the idea of “bacterial social intelligence”). They are not designs. they are only results. The key difference? There’s no intelligence involved. Rivers carve the same sort of fractal fingers, and they only obey the rules of gravity and friction. 

The science of decisionless decision-making is a fascinating one. Ed Yong covered it marvelously earlier this year in a must-read piece for Wired. Everything from fish schools (eyes on your neighbor) to locust swarms (don’t get bit by your neighbor) to honeybee hives (head-butt your neighbor until they agree with you) create complex behaviors from simple inputs and outputs.

There’s a reason that slime molds, nerve cells and city maps look similar. Simple rules applied at large scales beget complex results.

These microbes might not be that different from the above examples, which makes sense if you stroke your chin and ponder the math behind it all. But they’re certainly more attractive, and for that, they win the day.

Previous Bacterial Art: Bacterial galaxies! Alexander Fleming paints with microbes! Psychadelic biofilms!

Thanks to io9 for the link.