I tried with HSB. It didn't produce good results. The image was always too dark.

In HSB, colors that are far apart in our perception can have close distance. For example two colors with the same Brightness, Saturation but a different Hue.

Using HSB in the DNA was perfect. It's hard to mutate a RGB color in the right direction. You have to get 3 composants right. In HSB a single modification can change everything.

BTW, I coded a Java version after seeing the original. It works, but first, it doesn't converge very fast, second, it's stuck at: http://i33.tinypic.com/2yycdc8.jpg

On the bright side, I can easily switch the population size to 50. Java is very good at this. I piggy back on automatic hardware acceleration for rendering.

How did you get yours to converge sooo fast?!