culture

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

play

Imitation is the sincerest form of flattery – and bonding

Okay, first I just have to get it out of the way that Frans de Waal is a giant hippie. Big ol’ bio-anth hippie! The article I’m posting below undoubtedly reflects that. BUT, if you look past the hippiness, I think he’s onto something.

Okay, cue posting of Discover Magazine, general audience article about bonobos:

What intrigues me most about laughter is how it spreads. It’s almost impossible not to laugh when everybody else is. There have been laughing epidemics, in which no one could stop and some even died in a prolonged fit. There are laughing churches and laugh therapies based on the healing power of laughter. The must-have toy of 1996—Tickle Me Elmo—laughed hysterically after being squeezed three times in a row. All of this because we love to laugh and can’t resist joining laughing around us. This is why comedy shows on television have laugh tracks and why theater audiences are sometimes sprinkled with “laugh plants”: people paid to produce raucous laughing at any joke that comes along.

The infectiousness of laughter even works across species. Below my office window at the Yerkes Primate Center, I often hear my chimps laugh during rough-and-tumble games, and I cannot suppress a chuckle myself. It’s such a happy sound. Tickling and wrestling are the typical laugh triggers for apes, and probably the original ones for humans. The fact that tickling oneself is notoriously ineffective attests to its social significance. And when young apes put on their play face, their friends join in with the same expression as rapidly and easily as humans do with laughter.

Shared laughter is just one example of our primate sensitivity to others. Instead of being Robinson Crusoes sitting on separate islands, we’re all interconnected, both bodily and emotionally. This may be an odd thing to say in the West, with its tradition of individual freedom and liberty, but Homo sapiens is remarkably easily swayed in one emotional direction or another by its fellows.

Read the full article. I’ll wait.

Okay, are you back? Good.

I think he has a good point. There are lots of other data that really point out to me how important it is to have other individuals around, how much we learn from them, and how it’s hard for us to be the “lone wolf” (which doesn’t actually exist either, but that’s a different post all together).

The first type of play that humans participate in is imitating their moms and dads. Smiling at them, opening and closing their mouth the same way they do. Kids learn by mimicking and playing, trying the same stuff those around them do.

I don’t know if you need to go so far as to call it the new field of “embodied” cognition, but it is important to acknowledge that that part of us as social creatures definitely exists, and that basically, no man is an island. This is being re-shown every day.

language

Why chimps don’t talk?

All the news came out last week about the FOXP2 gene, but I can’t help and post it here a week late anyway:

Chimps, our nearest relative, don’t talk. We do. Now scientists have pinpointed a mutation in a gene that might help explain the difference.

The mutation seems to have helped humans develop speech and language. It’s probably not the only gene involved, but researchers found the gene looks and acts differently in chimps and humans, according to a study published online Wednesday by the journal Nature.

Lab tests showed that the human version regulated more than 100 other genes differently from the chimp version. This particular gene — called FOXP2 — mutated around the time humans developed the ability to talk.

“It’s really playing a major role in chimp-human differences,” said the study’s author, Daniel Geschwind, a professor of neurology, psychiatry and human genetics at the University of California, Los Angeles. “You mutate this gene in humans and you get a speech and language disorder.”

This tells you “what may be happening in the brain,” he said.

Read the full Associated Press story.

brain · neuroscience

Evolution of the mind

This is an older (from February) interview from Discover Magazine with Nobel laureate and neuro­scientist Gerald Edelman. Edelman is interested in studying what makes each human mind so unique, and thinks he may have found the answer: natural selection of the brain!

“Neurons proliferate and form connections in infancy; then experience weeds out the useless from the useful, molding the adult brain in sync with its environment.” His latest book, which I have no read, is called Second Nature: Brain Science and Human Knowledge.

I think this is an interesting theory, but need to read more about it before I feel comfortable forming any opinions on it. After reading the interview, let me know what you think.