Mik suggested having the people procreate and age and see what rate of infection would kill off the population. I say that is a good idea! Use the scale() method to 'grow' the images; with a variable to keep track of the age of the person. You could use this variable to adjust the chance of infection (the young are less likely to catch the infection). Also, the age could be used to make the un-infected die off even when not infected (chance of dying increases as age increases).
A new version of this scenario was uploaded on Tue Jun 28 03:33:55 UTC 2011
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