The link below happens to cross a couple of my interest zones, so I'm sharing it here.
It's an overview of an evolutionary genetics experiment, mutating simple simulated "organisms" to solve The Mario Problem. That is, how can successive generations of a creature with basic run and jump capabilities evolve to navigate a complex world of platforms successfully?
You can see that the first batch of generations gets a lot of Marios stuck in the lower, largely unnavigable path; the later batch gets farther, as those lowdown Marios failed to rescue the princess (i.e., breed) as successfully as the ones who took the higher road.
It's a nice visual demonstration of how genetic algorithms work -- with Mario!