Ok, thanks. I guess you know I'm talking about the latest version 2.4. I was just thinking that if I left all fields with 0's then the bots whouldn't have any metabolism or energy transfers at all, acting like frozen in time kind of state. I want it to be as close to realism as possible. Anyway, I haven't had much opportunity to try out this program's full potential as I keep getting runtime errors and crashes. I tried out the Darwin 2.37.4 version since last night. I start up a simulation, go away for a couple of hours, come back to find the program crashed, either frozen, runtime error or overflow. Graa! :angry: I guess I wont see any bots develop anytime soon, huh?