"My dear, Gaia! Please listen to me. From this time forward, every one billion years, you will have children called 'Life'. One of them will be able to help you to build a new era. Each child must endure a difficult trial. You might think it's too severe, but it is necessary. The trial is a test of nature: 'The survival of the fittest'. If he passes, I will allow him to be your partner and to enter Eden."
E.V.O. is one of those obscure old games for the SNES that haven't really been appreciated until people started playing them on emulators. The basic premise is that you guide a creature through the history of evolution. You start off as a simple fish in the Precambrian era, and go around beating up on the other animals you find to rack up on EPs, or evolution points. You can use these points to develop more useful appendages, sharper teeth, harder skin, and whatnot. After finishing a major age, you will face a level boss, and upon defeating him, you will mutate into a totally new kind of creature and advance to the next age.
The game is surprisingly fun to play, and while the premise may reek of edutainment, you don't actually learn too much. In fact I'm sure the diligent biology student would be quick to point out numerous problems with the trail of evolution the game uses. The later part of the game especially smashes any hope of educational value, bringing dragons and bizarre alien experiments into the picture.