(…) This explanation is based on the misconception that i have already mentionned, that living creatures evolve to do things ‘for the good of the species’ or ‘for the good of the group’. It is easy to see how this idea got its start in biology. Much of an animal’s life is devoted to reproduction, and most of the acts of altruistic self-sacrifice that are observed in nature are performed by parents towards their young. ‘Pepretuation of the species’ is a common euphemism for reproduction, and its undeniably a consequence of reproduction. It requires only a slight over-stretching of logic to deduce that the ‘function’ of reproduction is ‘to’ perpetuate the species. From thisit is but a further short false step to conclude that animals will in general behave in such a way as to favour the perpetuation of the species. ALtruism towards fellow members of the species seems to follow.
This line of thought can be put into vaguely Darwinian terms. Evolution works by natural selection, and natural selection means the differential survival of the ‘fittest’. But are we talking about the fittest individuals, teh fittest races, the fittest species, or what? For some purposes this does not greatly matter, but when we are talking about altruism it is obviously crucial.