Evolving Brains in the Life Engine (5 Year Anniversary!)

Life Engine is a free-to-play evolution simulator created by Emergent Garden, where digital organisms made of colored cells live on a grid, eat, move, reproduce, and mutate under simple rules that implement natural selection.

The Life Engine developer describes a JavaScript-specific performance trick—“update packing”—used to make the in-browser evolution simulator run several times faster without rewriting it in C++.

Life Engine’s “brains” are upgraded from simple stimulus–response tables to multi-state finite state machines, an intentional choice over using neural networks for organism control.

The Life Engine update introduces “symmetrical mutations,” a body-plan mutation rule where adding a cell in one location can also add mirrored copies, biasing evolution toward symmetric organisms.