Thicket. A meditation on speciation, evolution, and extinction.
This is the family tree of a single cell, branching downward through the generations. Each new cell descends from one of its neighbors in the last generation. A coin flip decides whether it descends from the left or from the right. It inherits its ancestor’s color, often with a little drift. A little drift adds up over time. As the colors become more vivid, your eyes might start to group them. You’ll tend to see group boundaries where neighboring cells’ lineages have been separated for a long time. If you watch a group for long enough, you’ll see its color drift as new variants spread through it. It will eventually either shrink to nothing or expand and diversify into many groups. Color has no effect on branching; all variation is neutral.