OK, I'll work this through for you.
The childs DNA doesn't say he is a wife beater, he might have got his Doa I beat my wife gene from his mothers side and that might be a don't beat your wife gene, but even if he get's it from his fathers side, it's unlikley to be a beat your wife gene, He'll probably loose his temper quite quickly, but he won't neccacerraly be pre-programmed to beat his wife, he could beat his temper by taking up yoga or some way of learning to control his temper. If we look at the Nurtur side, he could see the wife beating in one of two ways.
He sees wife beating as the done thing or
He sees how muich his mother is hurt by his father and goes against his fathers habits by not beating his wife, He has learnt by his experience, because his DNA tells him to.
also he could start out by seeing it happen and believing that this is what happens, but other influences could suggest this is wrong.
we do not need this 3rd influence to explain why people do not take ater their parents, there are so many influences and so many ways he could be influenced that he could turn out in any way at all.
