Artificial-life sims have always been lots of fun, except for one problem: For decades, the “life forms” have only existed on the computer screen, so they’ve never seemed very real. This all started to change with the Internet and video games, where the action of real life itself takes place — bien sur — on the screen. When you’re an avatar in a virtual world, the line between who’s “real” and who’s “artificial” is much easier to blur.

A brilliant example of this is the work of Surina Skallagrimson, a resident of Second Life, the increasingly-popular 3D immersive game-world. Second Life has a simple scripting language that allows users to create their own in-game stuff; recently, Skallagrimson decided to create a school of fish. She wrote a script to govern the behavior of an individual fish, then made hundreds of copies with slightly different attributes: Some could swim fast, others could see farther, and so on. Then she turned the fish loose in Second Life’s ocean to see what they’d do. Most of ‘em just wandered around aimlessly, so she killed them off; the few that seemed to behave more purposefully, she kept.

She did this a few hundred times and, in essence, created her own little evolutionary hothouse — such that she now has a school of fish that behaves very, uh, fishlike. (Fishy?) Anyway, Wagner James Au — the writer who pens a brilliant blog reporting on the goings-on inside the world of Second Life — recently met up with her at the bottom of the ocean, where she showed off her school. As Au notes:

The gold standard for any creator of artificial life is unplanned emergent behavior, and Surina has noticed at least a couple instances of these. For one, with enough fish in the school, they begin to move in circles. “[T]hey tend to form a line. And if the front moves around so it ‘sees’ the back of the line, they circle.” With the addition of food, she’s also noticed that “the weaker ones tend to lead the shoal. They are the ones most in need of food. The ones most in need of food will tend to break away from the shoal. This causes the rest of the shoal to follow, so you end up with the weakest near the front, heading for food.”

(Thanks to W. James Au for this one!)