Evolve
Bones joined by muscles that pull in and out on a rhythm and feel the ground under them. Whichever creatures get furthest have children. Nobody drew any of them.
generations, up to 2000
More controls
A muscle can pull harder when the foot at its end takes weight, when the body tips, or when the ground ahead rises. How much of each is bred like everything else. Turn reflexes off and the muscles keep only their rhythm.
This run started from seed 0. Everything after that is decided by it, so the same seed and the same number of generations give the same animal whether you sit and watch or run ahead. Start over picks a new one, and adding ?seed= and a number to the address uses yours.