Five offspring of a couple in a remote area of Turkey grew up walking quadrupedally on their hands and feet, as portrayed in the popular science documentary ‘Family That Walks on All Fours.’ Among the various angles of research on the siblings was genetic analysis identifying a mutation in a gene on chromosome 17 influencing cerebellum development and the work of certain 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. Moreover, 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.
Adapted from P. Taylor, “Infrastructure and Scaffolding: Interpretation and Change of Research Involving Human Genetic Information,” Science as Culture, 18(4):435-459, 2009
(Introduction to this series of posts)