This is a fascinating article on how nature and nurturing work together. Apparently there was a study done in New Zealand starting in 1972, which showed that children were much more likely to grow up to be aggressive and antisocial if they had inherited a "short" version of a gene called MAOA. This short version is worse at breaking down neurotransmitters like serotonin than the long version.
But the kids in the study only went ballistic (as they were genetically pre-disposed to do) when they had some crisis in their lives. The article is about a duplicate study done on monkeys.
Possible results of the study are "prenatal screening tests which ensure that infants at risk receive optimal mothering in their first two years of life." I can't imagine what they would have in mind.....
But I think this whole thing is fascinating because it is really making me think about the extent to which our state of mind controls our entire body on a very physical level.
I also think it's funny how they only look at the level to which the monkeys have been "mothered" as thought the presence or absense or potentially violent disposition of a father would have no effect...