The genes hold culture on a leash. The leash is very long, but inevitably values will be constrained in accordance with their effects on the human gene pool. The brain is a product of evolution. Human behavior—like the deepest capacities for emotional respone which drive and guide it—is the circuitous technique by which human genetic material has been and will be kept intact.
A new study co-written by Dr. J.C. Barnes of UT Dallas (my alma mater) demonstrates that lifelong criminals have a strong genetic predisposition for their lifestyle. In their study, they reference three types of subjects. 1)Life-Course Persistent (LCP), 2)Adolescence Limited (AL) and 3)abstainers. Using data from over 4,000 people drawn from the National Longitudinal Study of Adolescent Behavior and combining that with twin methodology(which is designed to measure the extent of genetic influence upon a certain trait), the authors conclude,
genetic factors played a role in the etiology of the two LCP offending groups, in the AL offending group, and in the group of abstainers.
Genes did not play an equal role in each group however.
Genetic influences accounted for a larger proportion of the variance for the LCP offender groups (both the top 20 percent grouping and the top 10 percent grouping) as compared with the AL offender group. The proportion of variance explained by genetic factors for abstaining behaviors was also larger than the proportion of variance explained by genetic factors for AL offending.
Another recent study published in the journal Nature, suggests that social behavior evolved in response to the increased predation primates experienced when they started becoming more active in the daytime. In his review of the paper Nicholas Wade of the New York Times writes,
the new survey emphasizes the major role of genetics in shaping sociality. Being rooted in genetics, social structure is hard to change, and a species has to operate with whatever social structure it inherits.
And another study also from Nature that looks at genetic contributions to the stability of intelligence from childhood to old age. The researchers used genome-wide single nucleotide poloymorphism (SNP) data from nearly 2000 individuals who had their intelligence measured at age 11 and again in old age (65,70 or 79). From their findings the authors conclude that,
Genetic factors seem to contribute much to the stability of intelligence differences across the majority of the human lifespan.
Studies like these should not come as a surprise but there is still a very vocal movement of academics and professionals who wish to discount the role of biology in human behavior. Instead of looking at human behavior as another trait linked to adaptation they place all or most of the responsibility on societal attitudes and biases. They then label those of us who disagree as genetic determinists or something similar. And yet none of them can ever point to a single individual who discounts environment completely from shaping human behavior. Meanwhile the blank slaters pat themselves on the back for tearing their own concocted straw man to pieces.
1. BARNES, J., BEAVER, K. M. and BOUTWELL, B. B. (2011), EXAMINING THE GENETIC UNDERPINNINGS TO MOFFITT’S DEVELOPMENTAL TAXONOMY: A BEHAVIORAL GENETIC ANALYSIS. Criminology, 49: 923–954.
3. Susanne Shultz, Christopher Opie & Quentin D. Atkinson. Stepwise evolution of stable sociality in primates Nature 479, 219-222 (10 November 2011)
4. Nicholas Wade. “Genes Play Major Role in Primate Social Behavior, Study Finds.” New York Times on the Web Dec 19,2011. Feb 10 2012.
5. Ian J. Deary, Jian Yang, Gail Davies, et al Genetic contributions to stability and change in intelligence from childhood to old age. Nature (2012) doi:10.1038/nature10781