My Genes Made Me Do It: Self-domestication

If you think you are being surrounded by idiots, you are probably right. A leading Stanford University scientist, Gerald Crabtree, would confirm your view. His idea is that since individuals are no longer exposed to nature’s raw selection mechanism on a daily basis that nearly all of us are genetically compromised compared to our ancestors of 3,000 years ago.

This and the previous blog are notes from the Coursera: ’Genes and the Human Condition’, University of Maryland, lectures on “My Genes Made Me Do It”. What follows is from lecture 5.

Crabtree gives the following example: "If a hunter-gatherer did not correctly conceive a solution to providing food and shelter probably died along with his or her progeny. Whereas a modern Wall Street executive that made a similar conceptual mistake would probably receive a substantial bonus and a be a more attractive mate". In other words, the consequences of being stupid were much worse in the Stone Age.

What is Self-domestication? - it is a process of transforming ourselves through self selection. What are some of the traits? We are selecting against aggression and favoring the juvenile behaviors  of trust, playfulness, and creativity. Both in brain size and physiology, we can be considered to be sexually mature baby chimps. This process is called paedomorphism, where the adult retains their infantile or juvenile features. Like most domesticated animals we have a smaller brain than our progenitors. Our brains have shrunk by about 20% in the last 10,000 years. The area that seems to have decreased in size is Area 13 which is the part of the limbic brain that establishes adult emotional reactions such as aggression.

Gerald Crabtree thinks we reached a peak in our intelligence about 7,000 years ago, but he doesn’t think our decline relates to our domesticating of ourselves. His argument is based on the idea that for more than 99% of human evolutionary history, we lived as hunter-gatherer article-crabtree-1112communities, surviving on our wits. However, since the invention of agriculture and cities and technology, natural selecting on our intellect has effectively stopped. He suggests that this has allowed mutations to accumulate in the genes involved in intelligence on average 25 - 65 per generation. He predicts the 5,000 new mutations in the last 120 generations, which is about 3,000 years, are the cause of our decline. He gives an interesting illustration: “I would wager that if an average citizen from Athens of 1000 BC were to appear suddenly among us, he or she would be among the brightest and most intellectually alive of our colleagues and companions, with a good memory, a broad range of ideas, and a clear-sighted view of important issues. Furthermore, I would guess that he or she would be among the most emotionally stable of our friends and colleagues. I would also make this wager for the ancient inhabitants of Africa, Asia, India or the Americas, of perhaps 2000–6000 years ago. The basis for my wager comes from new developments in genetics, anthropology, and neurobiology that make a clear prediction that our intellectual and emotional abilities are genetically surprisingly fragile.”

In today’s world we compensate for having a smaller brain or a more mutated one by using computers and technology. We also have an education system that provides the supportive environment to allow what brain power that remains to attain its potential. Education allows those strengths to be rapidly distributed to all members of our society. What we need to do is educate Athenians.

For a mash up of the video from Coursera; Genes and the Human Condition, University of Maryland by Professor Raymond St. Leger -- see below:

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