Human quadrupeds: Social infrastructure (or its absence) makes genetic conditions hardwired
‘Family That Walks on All Fours’ is a popular science documentary on the United States Public Broadcasting Network (2006). Five offspring of a couple in a remote area of Turkey have grown up walking quadrupedally on their hands and feet. The documentary describes various angles of research on the siblings: MRI brain scans show a reduced cerebellum, the region of the brain controlling balance and movement; genetic analysis identifies a mutation in a gene on chromosome 17 influencing cerebellum development; and evolutionary biologists try to link this gene to the evolution of human bipedalism 3 million years ago. Indeed, other deleterious effects of the gene are depicted as reversing the progress in fine motor coordination and intelligence that accompanied human evolution. Scientific disputes arise over these interpretations. But then it is also observed that no medical treatment or physical therapy has been available since the children failed to shift from crawling to walking upright. Following the introduction of a simple walking frame, then exercising between parallel bars, the quadrupedal adults learn to walk upright.
The quadrupedal condition may have been genetic in origin, but it was the social infrastructure—or lack thereof—made it hardwired. Adjustments to that infrastructure then softened that wiring. Could the corollary also hold: The application of genetic knowledge to reshape human life will always involve reconstruction of the social infrastructure? Under what conditions—or crises—will that reconstruction become possible?
Another excerpt from P. Taylor, “Infrastructure and Scaffolding: Interpretation and Change of Research Involving Human Genetic Information,” Science as Culture, 18(4):435-459, 2009