JO, in order to make the case that sociobiology shapes human behaviour, we first need to accept two premises:
One: humans are biological matter
Two: we live socially
You being the expert on sociobiology and all things anthropological would of course know this...wouldn't you??????
"sociobiology's contention that genes play an ultimate role in human behavior and that traits such as aggressiveness can be explained by biology rather than a person's social environment. Sociobiologists generally responded to the criticism by pointing to the complex relationship between nature and nurture"
It seems that socio-babble turns to nurture when its nature argument fails. I agree with you that human nature changes over time and is adaptive but the reason isn't genetic but social.
Like language, we evolve over time and in doing so we use language and behaviour to enforce inequalities/conditions that might be considered in some way beneficial at any given point. We may even change in terms of appearance, physical strength, characteristics, traits and fertility because social phenomena, like the way in which we use and abuse the natural environment.
Look at pictures of men in the great depression, men that were out of work, they have lost body mass but retain some muscle, compare that to today's fat and lardy specimen of masculinity and we find that desk dweller or coach potato, men's appearance and physical strength is different to only 80 years ago. This due to not the survival of the fittest (what a laugh) but changes to the economic and social life of people. ie social change drives all change.
And whilst you might like to think that men are naturally driven to aggression because of natural selection, I don't, to do so overlooks the one thing that sets humans apart from other animals...something you yourself seem to lack...rationality.