This is a picture of a bacterial community, taken by Eshel Ben-Jacob, who thinks bacteria are both the key to understanding complex biological systems and a source of incredible art. These bacteria, discovered by Ben-Jacob's research team, self-organize into intricate and beautiful systems.
Bacteria are generally pictures swimming around by themselves, but they're not as solitary as they're made out to be. Many are quorum-sensing, meaning that when they detect a certain amount of them are present, they can build up into astounding complex communities.
Paenibacillus dendritiformis and the Paenibacillus vortex are two types of bacteria, both discovered by Eshel Ben-Jacob, a physicists-turned-biologist. They build up into massive colonies. The bacteria in each colony can exceed the number of people on Earth, so they make a bacterial super-city. Unlike most human cities, the bacteria can make beautiful structures as they grow their colony outward. Ben-Jacob takes pictures of those structures, tints them, and makes them into bacterial art.
Via Eshel Ben-Jacob.