xia@cc.helsinki.fi (10/29/90)
There is a difference between maintenance of a trait and evolution of a trait. Maintenance of a trait means that the trait will be favoured when it is already present in the population at a certain frequency, while evolution of a trait means that the trait will be favoured regardless how rare it is. I think that Hamilton's principle is for maintenance of the altruisim, after random drift has overcome natural selection and altruists has drifted to a certain frequency. (Won't we believe that random drift is an extremely powerful evolutionary force given the commoness of altruism claimed in numerous number of papers?) To convince others that altruism will evolve by kin selection, one has to specify realistic mutation rate for such trait, how 'lethal' it is to its carrier given a certain population structure and breeding system, how effective it is to increase the fitness of others, etc., and, based on these, find out how many generations are required for such trait to overcome the initial disadvantageous stage and whether the number of generations required is a realistic number. Xuhua