Gets to ~97% in the first few minutes and then takes a long time hunting for very small gains. I was hoping to see more dramatic improvement after the first couple of minutes as well, but I was amused by the thought that followed after my evolving image failed to look successively more like a Mondrian.
We were told early in public school that we share 98% (or some such very high number percent) of our DNA with our simian relatives. I always was amazed at how just small a section of the genome was responsible for such amazing diversity among primates, or even mammals in general.
Seeing the wild differences that result in these images when you're given 3% of leeway between generations really helps me appreciate the vast number of individuals in our species!