Field guide
β Purple-red fish β speed-dominant gene (fast, but energy drain β speedΒ²).
β Neon-blue fish β vision-dominant gene (sees far, costs energy).
β Green fish β size-dominant gene (hard to kill, high metabolism).
β Red sharks β predators; starve if they fail to hunt.
Each fish is steered by its own 5-4-2 neural network. Successful survivors clone themselves; offspring inherit mutated brains & genes.