I modified Paul's last NetLogo program so that the ant doesn't base his moves purely on how successful a bold or safe move has been in the past, but rather on how successful each type of move has been from his current color patch. That is, there is a success ratio for a bold move from a yellow patch, a bold move from a black patch, a safe move from a yellow patch, and a safe move from a black patch. In the clumpier setups, he learns pretty quickly to move safely when on yellow and boldly when on black. Java Applet NetLogo source