The 10,000 Year ExplosionPosted: April 5, 2012 | Author: Greg Linster | Filed under: Reviews | 3 Comments »
The evolutionary biologist, Steven Jay Gould, once famously said that “There’s been no biological change in humans in 40,000 or 50,000 years. Everything we call culture and civilization we’ve built with the same body and brain.” Nonsense say University of Utah anthropologists Gregory Cochran and Henry Harpending. Their book, The 10,000 Year Explosion, dismantles Gould’s claim in elegant fashion by arguing that human evolution has not stagnated, but rather, it has actually accelerated rapidly. In fact, so much so that it “is now happening about 100 times faster than its long-term average over the six million years of our existence.”
If this sounds a bit far fetched, then consider the work of a Russian scientist named Dmitri Belyaev. In the 1950s, Belyaev and his team bred silver foxes by selecting only those individual foxes that showed the least fear of humans. After roughly ten generations of controlled breeding, the domesticated silver foxes showed significant changes in their nature. They no longer showed any fear of humans and often wagged their tails and licked their human caretakers to show affection. In other words, they became dogs.
Now, humans and foxes are certainly different, but if foxes can evolve into dogs in such a relatively short time period, shouldn’t we consider what this might mean for human evolution? At the very least, this should make us consider what happens to our brains, biological makeup, and behavior after major environmental changing events (e.g. the agricultural revolution or the rise of the Internet).
Cochran and Harpending, who run a blog called West Hunter, essentially argue that the adoption of agriculture has dramatically altered the course of human evolution. And there is plenty of evidence to confirm that genetic innovation has run rampant since the dawn of agriculture. For example, the gene that allows one to tolerate lactose appears to have arisen in Europe about 8,000 years ago among the first humans who herded cows and other milk-producing animals.
The authors claim that the lactose-digesting gene quickly spread throughout parts of Eurasia. New genetic variants, like the one that allows people to tolerate lactose, thrived namely because it helped people cope with the challenges an agricultural way of life presented. Is a similar effect happening now to those of us who are constantly plugged-in? I can’t help but think that there are changes going on in my brain from all the information I consume in the modern digital world.
Jared Diamond, for one, has argued that the agricultural revolution was the worst mistake of the human race. Then, there are those who argue that the industrial revolution was the worst mistake of the human race. And now I’m sure there those who argue that the digital revolution was the worst mistake of the human race. Cochran and Harpending, however, ultimately refrain from anthropomorphically commenting on whether or not any of these events are “good” or “bad”. Cochran and Harpending do acknowledge, however, that most hunter-gatherers were egalitarian anarchists. As they put it, “They didn’t have chiefs or bosses, and they didn’t have much use for anyone who tried to be a boss. Bushmen today still laugh at wannabe “big men”. Perhaps we could learn from them.” Touché!
With agriculture came the rise of elites (defined as those who live almost solely off the work of others), who are clearly still a nuisance today. Agriculture certainly enabled the rise of strong governments (although forms of governance arguably already existed). Strong governments need individuals as citizens who can be “tamed” (like the Russian foxes) in order to function properly. Not surprisingly, peoples with little or no exposure to agriculture tend to be less submissive, on average, than members of longtime agricultural societies. As the authors put it: “One possible indicator of tameness is the ease with which people can be enslaved, and our reading of history suggests that some peoples with little or no evolutionary exposure to agriculture ‘would not endure the yoke’, as was said of Indians captured by the Puritans in the Pequot War of 1636.” The authors also remind us that the Bushmen have been described as the “the anarchist of South Africa” for a reason.
As an evolutionary health enthusiast, I found the parts of this book that related to human diet and health very interesting. This book should make open-minded and well informed evolutionary health enthusiasts question some of their own basic assumptions and arguments. Are all grains as bad as some Paleo zealots make them out to be?
Near the end of the book, Cochran and Harpending make the controversial argument that people of Ashkenazi Jewish descent (European Jews) have, on average, evolved a higher level of intelligence relative to other ethnic groups. Politically incorrect as it may be to say, the evidence seems to confirm that human races are truly genetically different at some levels (although they are indeed mainly similar). Back in 2010, it was even confirmed that most of us have at least a little neanderthal in us.
This book is mischievous, humorous, lively, and very educational. In the end, Cochran and Harpending remind us that “history looks more and more like a science fiction novel in which mutants repeatedly arise and displace normal humans –sometimes quietly, simply by surviving, sometimes as a conquering horde.” I think it’s fair to say that without a doubt Steven Jay Gould was grossly mistaken. After reading this book, I’ve only been left to wonder about where exactly evolution plans on taking us.