Complexity Theory May Inform Socio Biology

Image: RYAN SNOOK via Science

Science magazine (7 November 2008) has a news article on the genetic factors that influence human behavior. It notes that the warrior MAOA variant of the gene for monoamine oxidase-A (MAO-A) has been implicated in male aggressiveness. The variant is found in 60% of Asians compared with 40% of Caucasians.

But the gene variant isn't all that matters. Caspi's Dunedin study has shown that the environment--in the form of traumatic life events--plays a critical role in how this gene is expressed. Caspi's group reported in 2002 that the warrior MAOA variant is associated with violent and antisocial behavior but only in people with a history of abuse as children. These men were 2.8 times as likely as nonabused males with this genotype to develop behavioral problems that are often the precursor to a life of crime and drug abuse. Children with a different variant were less likely to develop antisocial problems in response to maltreatment

The article raises the controversial question as to whether the aggressiveness that seems to be characteristic of Maori society can be traced to the frequency of the warrior variant in Maori people. (I wonder whether there are not other Asian societies, with equally high levels of the warrior gene in their peoples, which are notable for their pacifism?)

Comment: It occurs to me that complexity theory may be useful here. Would a society in which 40 percent of people carried the warrior variant function differently than a society in which 60 percent carried the variant? The variant is known to influence subsequent behavior if the individual experiences certain kinds of stress in his life. It could be that there would be a positive feedback in which people with the activated variant are more likely to create the conditions in which the variant would be activated. It might be that there would be a whole lot more male aggressiveness in a society with 60 percent of the population carrying and transmitting the warrior variant than in one with 40 percent, simply because the gene makes it more likely that the conditions will be created by each generation to result in aggressiveness being expressed by the next generation.

I am not arguing that genetic determinism exists, but simply that it may be that there may be a social process that combines a genetic predisposition and environmental triggers to make a significant change in societal behavior.

I recall that Orhan Pamuk, in his book Istanbul, remarks that the city of Istambul has a general mood of sadness, and that other cities too have been known for their own individual moods. It may be that the genetics of inhabitants lead to proclivities that influence behavior, that in turn influence in such ideosyncratic social moods. Who knows? JAD