There’s a fascinating story in yesterday’s New York Times about some new insights into the role culture itself plays in human evolution (and yes, I’m sure I’ll get chided by some of you, again, for referencing such a liberal rag). Historically, most scientists have discounted the role of culture in our evolutionary history. In fact, the rise of agriculture and organized civilization has always been seen as a speedbump for the natural evolutionary forces shaping our ancestors. But the thinking on this is changing.
From the story:
As with any other species, human populations are shaped by the usual forces of natural selection, like famine, disease or climate. A new force is now coming into focus. It is one with a surprising implication — that for the last 20,000 years or so, people have inadvertently been shaping their own evolution. _The force is human culture, broadly defined as any learned behavior, including technology. The evidence of its activity is the more surprising because culture has long seemed to play just the opposite role. Biologists have seen it as a shield that protects people from the full force of other selective pressures, since clothes and shelter dull the bite of cold and farming helps build surpluses to ride out famine. Because of this buffering action, culture was thought to have blunted the rate of human evolution, or even brought it to a halt, in the distant past. Many biologists are now seeing the role of culture in a quite different light.
Although it does shield people from other forces, culture itself seems to be a powerful force of natural selection. People adapt genetically to sustained cultural changes, like new diets. And this interaction works more quickly than other selective forces, “leading some practitioners to argue that gene-culture co-evolution could be the dominant mode of human evolution,” Kevin N. Laland and colleagues wrote in the February issue of Nature Reviews Genetics. Dr. Laland is an evolutionary biologist at the University of St. Andrews in Scotland.
The whole story is well worth a read, and if true, raises some interesting questions about hunting, its role in evolution, and how it’s generally perceived in modern society. My first question on reading the story was “OK, just how fast are they talking here? Millenniums? Centuries? Could culture exert an influence on evolution in the space of just a few generations?
If true, the possibilities are fascinating, if a little frightening. As outdoors persons, we all worry about the long, slow, society-wide decline in not only hunting and fishing, but general interest in nature itself. And traditionally we’ve lamented that decline as a cultural problem. But if current cultural norms and conditions do indeed have a hand in hard-wiring our genes, what might that say about our future? What traits would modern society select for? What will the human of the future look like?
For example, my wife is a high school teacher, so I am an observer of the teenage condition. And thanks to the children of today, I believe the human of the future will not need the hand as we currently know it. Instead, our hands will evolve into cupped flipper-like appendages with an iPhone-shaped indent and two prominent and blindingly fast thumbs. Why? The teens and young adults with superior thumb speed text more quickly and will be more successful at hooking up with potential mates and employers. They will consistently beat out their slow-thumbed competitors, and therefore be rewarded with propagating their traits. A few generations down the line, a few more rounds of selection and Bingo! The iFlipper is born. Simple natural selection at work.
So there’s my vision. What’s yours?