Karl Sims, US computer programmer at Thinking Machines Corporation. Sims created an 'Artificial Life' program which simulates evolutionary theory. The program starts with very simple 'creatures', whose aim in life is to 'capture' cubes found in their electronic environment. When the creatures reproduce, random mutations arise in their 'genes' which may invoke a functional advantage in being able to capture a cube. This increases their probability of reproduction, and thus of passing on their genes. After about 100 generations, creatures evolve - as seen on the monitor here - which have limbs, move around with ease, and display aggressive behaviour. Photographed 1994.