The scene is this year's e3 ( Electronic Entertainment Expo). Thousands of game junkies crowd around a giant video screen to witness the latest pinnacle of game programming: a little green bacterium in a pond of primordial goop.

The usual Vegas-style booths advertising the latest first-person shooters empty out as technophiles grab at the opportunity to watch, enraptured, as the bacterium slowly evolves into a multi-celled organism, then a land-dweller, and finally a social being complete with buildings and spaceships. The 20-minute demo is a preview of Spore (www.spore.com), the latest game by Will Wright, the creator of The Sims.

The game reprises the open-ended structure of The Sims, where the usual gaming formula is reversed: usually, a gamer controls a main character in an environment of pre-set rules, but in The Sims, the player controls the environment, and the characters develop lives of their own.

The focus of Spore is nothing less than the evolution of life itself, a fact sure to please the intelligent design lobby.

Once you prove your worth in the primordial stew by eating smaller, weaker bacteria, you use DNA points to facilitate growth of complex structures, eventually allowing users to make decisions that would make Darwin swoon, such as trying out various adaptive features like green skin or sharper teeth.

The virtual world of The Sims, released in 2000, made headlines by attracting more women players than men; a rarity in the male-dominated world of gaming.

The popularity across gender and generational divides spawned a slew of spin-offs including SimFarm, SimAnt, SimEarth and SimCity, the last of which was used by many city planers to prep eager apprentices.

Similarly, Spore seems to be of interest to everyone from game geeks to casual players, and even science teachers anxious to promote the fundamental principles of natural selection. I can hear the collective happy sigh of biology teachers the world over as they hear the words of a stoned gamer: "Dude, you've totally got to get a flagellum to move better."

Although graphically innovative, Spore is not the first instance where the complexity of life has been modelled through a gaming platform.

In 1970, mathematician John Conway developed The Game Of Life, a set of animations showing how initially straightforward patterns can evolve into surprisingly complex shapes based on a simple set of mathematical rules.

The Game has been used to illustrate the principles of complexity, which allow for so-called "emergent behaviour": completely unpredictable patterns can emerge from a simple set of conditions.

Emergent behaviour is clearly evident in Spore. With one of his creations, Wright combined the action of eating with the action of movement and found to his surprise that the creature eventually decided on its own to drag its future prey to a set place for dinner.

Once you've paid your dues mucking around in the prehistoric jungle, your creatures can form societies and complex communities, perhaps even venturing into space. The game itself is linked to other players online, so you can meet creatures on other planets that are the results of another player's game.

Here, Spore veers into the territory of game theory, a philosophy that describes evolution as a scenario where creatures can either conquer or co-operate with new species, depending on the net benefit to their society.

Simple interactions with other animals in Spore can lead to some pretty unpredictable results, something familiar to anyone who's tried to apply game theory to the world of international relations.

So when Spore hits shelves in late 2006, try your hand at what Will Wright has called SimEverything, and see if you can survive as one of its fittest.