Sunday, November 12, 2006

The Genetic Basis for Behavioral Differences

Dmitri K. Belyaev studied the genetics of domestication in an animal breeding farm in Siberia. In 1959 he started developing colonies of silver foxes. Belyaev hypothesized that the single criterion that led to domestication was selection for tameness. He tested his hypothesis by breeding silver foxes, an animal which had remained wild, despite being kept on farms for about 50 years by fur farmers. After 40 years of the experiment, "a group of animals had emerged that were as tame and as eager to please as a dog...they were clean and quiet and made excellent house pets."

I found it interesting that this species that had been aggressive and wild could be bred into a domesticated pet by only letting the tamest of the silver foxes mate. Is the effect genetics plays on our behavior greater than we think? Applying the findings of this experiment to humans seems to suggest that the offspring of aggressive parents are much more likely to be aggressive themselves because they either have an "aggression gene" or lack a "tame gene." Could the end to human rights abuses actually lie in the hands of geneticists? Currently the technology to silence a targeted gene is readily available. We also know how to determine the role of genes. If there is a gene for aggression and we know where in our chromosomes it lies, we will have the potential to "domesticate" the most vicious criminals.

3 comments:

stacy h said...

As a psychology major, I am repeatedly reminded of the interaction between both nature(situation) and nuture(disposition) when describing various phenomena. Therefore, I believe that evil behavior cannot only be cured by changing specific genes. Yes, aggressive behavior definitely has a genetic factor, but if all people with genetic defects were identified and then cured, there would still be many people who grow up in harsh or poor environments that could lead to the development and persistence of evil/bad behavior.

Also, another issue is that focusing on particular genes for aggression would not be able to limit all avenues that breed evil behavior. For example, people might lack the gene(s) linked to aggression, but have mental disorders (e.g. bipolar disorder, schizophrenia, etc.) that lead to uncontrollable behavior that in turn is evil. Although it's important to recognize how genes are linked to behavior, I think it would be a mistake to ignore environmental factors and other biological factors that can lead to evil behavior.

Rme said...

I have a great interest in Sociology and in my criminology class we have just been discussing this very topic. There are two schools of thought. First there is the Classical school which argues that all humans have free will and therefore we have total control over all of our actions. The second school is callled Positivism which states that you can use scientific method to explain criminal behavior because all behavior is a cause and effect or stimulus and response reaction. Positivism therefore implys that we have no free will. We are either driven by biological malfunctions, or by enviormental and situational circumstances. I stuggle with this concept because no matter where you grow up or how you are raised the decision to do evil is yours.

I like to explain criminal human behavior by combining the two schools of thought. I believe that some people are born with biological abormalities, and that might be having an "aggressive gene" or it might be that the prefrontal cortex of the brain never fully develops, or it might be that a person has a mental disease. However, I do not believe that a person who robs someone and then shoots them has a genetic discrepency. I think they made a choice to rob someone and then shoot them. Perhaps situational circumstances compelled them to commit the robbery, but the decision was theirs, and no number of geneticists can explain that decision. I think science can only explain so much when it comes to human behavior.

hewhowould said...

Great article but I fear what the research will produce. Let say there is a gene that can be removed or suppressed by a drug. I personally would not like to see anyone undergo surgery or take pills to suppress an aggressive gene. Reminds me of a government conspiracy as seen in the movie, Equilibrium. But I have seen people on heavy medication because school said they were too aggressive or way to wild and thus had to take Ridilin and they were never the same again. Their whole personality changed and they lost that creative side that made them unique. I would prefer to maintain my aggressive side and deal with the issue of having to make a good or evil decision.