Neutral Evolution Now let’s add some additional players. At first, they make no contributions to the final score. They are just bystanders while player 1 completes the whole room.
Then we let their genomes mutate, only requiring that collectively they maintain the same score. What can then happen over time is that some of the other players start scoring points. Subsequently, player 1 develops mutations such that he can no longer get a perfect score by himself. All of these mutations are neutral with respect to the team score in the room. And we go from a 1 component solution to a 4 component solution, which is more complex. Yet the fitness function does not select for more components, and the individual mutations that allowed the other players to score points were not selectively advantageous either. The increase in complexity occurs purely by neutral drift.
