''I've said this before on this forum, and I'll say it again here: I consider human altruism evolutionarily explicable in the same manner as is sickle cell anemia.''
I hate the word ‘’evolution’’ in the context of the theory of natural selection. If you look up the word in the dictionary it just means change. Who in their right mind in isolation can argue against change? Those of us who have some doubts and qualifications are therefore almost on a loser from the start by going along with the terminology, however, moving on.
As you raise it lets talk about sickle cell anaemia in the context of altruism. First a couple of premises that the natural selection hypotheses dictates that we accept;
1) The underlying mechanism for evolutionary change is proposed to be genetic mutation, which confers an advantage to the organism in both a particular and randomly formed environment (although please see my last post which questioned the randomness of the environment).
2) Every species of living thing that has ever existed has evolved from a pre-existing species (apart from the very first, but that is for another very interesting debate). A new species might be said to be in place when the genotypes are sufficiently different, so as to grossly forestall interbreeding.
A fact on sickle cell anaemia:
1) Although the genotype results in a phenotype which expresses itself as pathology of the blood, it does confer resistance to the malaria parasite carried by the mosquito.
Now let us imagine a world of runaway global warming where the mosquito becomes much more geographically extensive then it is now. We might also imagine a world where civil chaos means that insecticide and/or medicine supply is interrupted to the general population. Or perhaps, my favourite, a world where the mosquito and/or malaria parasite have themselves evolved to be immune to any containing measures and/or drugs we humans might employ. It is changes in the environment such as these which are often quoted as being the drivers of evolution. (Although, it is a little beside the point to discuss the gradualism v. catastrophic competing evolutionary theories. I can do that if you like; I have in mind the long neck of the giraffe as an example)
The guys who have sickle cell anaemia will then be at a distinct advantage. They will almost certainly go on to form distinct communities of fit individuals and evolve further advantages characteristics. We might then call them a proto-species or, if you prefer a race. Now I can hear the rebuttals already along the lines of – ‘’oh, but we humans are different, we have air travel and geographical isolation could not possibly apply to us’’. Anthropocentric piffle, you either embrace the idea of a multi-billion year chronology of evolution (the interaction of differing genotypes on a random environment) of which we are but an infinitesimally tiny part, or you don’t.
Viewed in this context any idea of an altruism which applies to the whole species or, if you prefer, the human race, is romantic nonsense. A reciprocal altruism purely based on our own kin group or as I prefer to put it our ‘’hunter gather group’’ might have some legs. I would only caution that you should be careful what you wish for.
To give credit where it is due I believe that Dawkins himself, in the context of the human race has made an appeal for us to rise up our evolutionary origins (or was it impulses?).
Some of us, however, believe in true altruism or, if you prefer, a brotherhood of man, for other reasons, which are perhaps not strictly relevant to this discussion. Just to note that there is an alternative point of view.