Thanks - my assumption was that the speedup in dying would increase the reproductive pressure and make the whole process a lot more competitive. But GAs are not my specialty (far from).

I am indeed very curious, but also very, very short on time! Before I can justify picking up someone else's code I have a couple of pieces of coursework and a dissertation to work on - but I might get some time round abouts next weekend, I'll let you know how I get on :)