NYT: "Human Culture, an Evolutionary Force"

Ha ha!
 By NICHOLAS WADE, New York Times

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.

Read full article


Cultural evolution seen in polynesian canoes

Despite the popularity of cultural evolution as an idea, with cultures as organisms and memes as genes, the actual science has lagged.

But by applying the tools of population genetics to Polynesian boat designs, researchers show that cultural evolution might be studied as rigorously as the beaks of finches.

“Evolution is a logical way of looking at change over time,” said Deborah Rogers, a Stanford University evolutionary biologist. “There’s nothing inherently biological about it. The logic can be applied to cultural change. Biology was just the first place that people ran with it.”

Working with fellow Stanford researchers Marcus Feldman and Paul Ehrlich, Rogers converted archaeological records of Polynesian canoes, the design of which varied between islands and tribes, into standardized descriptions.

The structure of that dataset was described in a paper published last year in the Proceedings of the National Academy of Sciences. In the latest study, published in the November Proceedings of the Royal Society B, the researchers ran their data through a program of the sort typically used to analyze genetic information, inferring trees of relationships from patterns of inherited biological difference.

Read full story and compare pictures at the original post on Wired Science.


Reblog: Culture doesn’t develop the same way as genes

I saw this post by Brandon Keim at Wired Science discussing a paper by evolutionary game theorist Arne Traulsen and his gang at the Max Planck Institute, titled “Exploration dynamics in evolutionary games,” and just HAD to re-post it, mostly because it just seemed like it would push some buttons:

“In a paper published Monday in the Proceedings of the National Academy of Sciences, Traulsen and colleagues modeled the effects of mutational variance in a standard game-theory model where individuals can be part of a community, steal from that community, or punish the thieves.

Most models of behavioral evolution, said Traulsen, assume that individuals will imitate their successful neighbors, with a minor allowance made for random variation — the cultural equivalent of heredity with minor mutations.

But in reality, people are unpredictable, prone to whimsical explorations and rash, seemingly irrational decisions. And when Traulsen reduced imitation and increased randomness, his simulations produced different end-states, with cooperation finally triumphing over thievery.”

Read Keim’s full post.

Keim seems to think this is a big, grand statement to be making, but to me this is fairly obvious stuff; that humans are greedy, ingenious people who will adapt to different situations in different ways. That’s why we have so many different cultures around the world.

Although I suppose if people like Alan Greenspan thought better of the human race, than other people would be surprised by these findings too.

Citation: “Exploration dynamics in evolutionary games.” By Arne Traulsen, Christoph Hauert, Hannelore Brandt, Martin A. Nowak, and Karl Sigmund. Proceedings of the National Academy of Sciences, Jan. 5, 2009.