Cultural Selection
Don’t you love it when something you’ve been harping on is supported by hard evidence? Biologists are discovering that culture is affecting evolution at the genetic level:
The best evidence available to Dr. Boyd and Dr. Richerson for culture being a selective force was the lactose tolerance found in many northern Europeans. Most people switch off the gene that digests the lactose in milk shortly after they are weaned, but in northern Europeans — the descendants of an ancient cattle-rearing culture that emerged in the region some 6,000 years ago — the gene is kept switched on in adulthood.
Lactose tolerance is now well recognized as a case in which a cultural practice — drinking raw milk — has caused an evolutionary change in the human genome. Presumably the extra nutrition was of such great advantage that adults able to digest milk left more surviving offspring, and the genetic change swept through the population.
This instance of gene-culture interaction turns out to be far from unique. In the last few years, biologists have been able to scan the whole human genome for the signatures of genes undergoing selection. Such a signature is formed when one version of a gene becomes more common than other versions because its owners are leaving more surviving offspring. From the evidence of the scans, up to 10 percent of the genome — some 2,000 genes — shows signs of being under selective pressure.
And the working definition of “culture” in this article is “broadly defined as any learned behavior, including technology.”
Tags: Culture, Evolution, Genetics
Pop Transhumanism | Kyle Munkittrick | 
March 2, 2010 8:53 am
By meika, March 2, 2010 @ 4:24 pm
Background reading Baldwin Effect in evolution.
This maintaining lactose digesting in adulthood gene spread through populations unconnected with whatever ‘culture’ this mutation first appeared in. You don’t speak that cultures language I bet. nor believe in their gods.
You confusing plasticity of behaviour with ‘culture’. The more an animal has to learn rather than have hardwired behaviour set ingenes then it’s more likely to play and explore new territories and behaviours and be able to take advantage of any benefit a mutation may allow.
Maintaining a culture is also outcome of our large human behavioural plasticity. But cultural practices do not go through a genetic bottleneck and cannot be selected for.
EG I can digest milk as an adult but my Y chromosome is that of the original hunter-gathers in Europe and not the johnny-come-lately farmer types and cattlemen who prob brought the milk digesting gene in.
Also while the population grew with that new ability to drink milk as well as eat cheese, the populatin splintered into various cultures we know in Europe today. The is no singular domniant milk-drinking culture continuing in a thousand year reich for example.
Not that I would run over a cow in India you understand, even if I was tempted by my hunter-gather culture genes.