The 10,000 Year Explosion and Evolution

In 2009 Gregory Cochran and Henry Harpending utilized their merit as professors of anthropology at the University of Utah to publish a book detailing the recent history of evolution. The 10,000 Year Explosion: How Civilization Accelerated Human Evolution argues that human evolution accelerated from civilization due to new selective pressures and an increase of sample size for mutations. While Cochran and Harpending utilize past selective advantages like lactose tolerance or language capabilities, they lack evidence of current day selective advantages that are changing in the human genome. While the book is very convincing that evolution was ongoing pre civilized and early civilized humans, it lacks evidence on evolution in the current day.

The authors start the book with an evaluation on primitive peoples’ genome. The authors explain, “Modern humans had developed advanced language capabilities and were able to talk the neanderthals to death.”(26). This means people were evolving right up to the start of civilization because language enabled civilization. Also supporting that language was a genetic advantage rather than a cultural advantage was the fact that this quote implies humans could talk while neanderthals couldn't, which could only mean we had a genetic advantage to neanderthals. Changes were also evident in the fossil record: “The archaeological record of The Upper Paleolithic… is qualitatively different from anything that came before” (30). This means that humans were not only evolving subtle characteristics like language, but also skeletal changes that would make us distinct from the neanderthals. However, what sparked civilization must have been changes in the characteristics of human interactions to bring people together who years before would have been competing tribes. The authors have evidence for this as well when the say,” People… were acting different from their forebearers 20,000 years earlier” (30). Changes in act were almost certainly made in the genome because it is extremely hard to change the characteristics of every clan without a culture behind them. Using evidence of body and acting changes, the authors effectively argue that humans were evolving right up to the point of civilization.

However, the book proves evolution didn’t stop there. Changes in the human genome signal selective pressure changes were expressed in the human genome. The book continues, “Lactose-tolerant Europeans carry a particular mutation that is only a few thousand years old” (22). This means that the authors prove that humans changed to a diet of milk due to early herding and domestication. The authors also prove that hunter gatherers did not have this mutation through explaining,”Hunter Gatherers… stop making lactose in childhood (an enzyme that digests lactose)”(77). By making a genetic distinction between hunter gatherers and early civilized peoples, there is adequate evidence that evolution continued as nomadic tribes put down the spears and took up agriculture. The authors also stress the selective pressures due to agriculture by saying,”Agriculture reshaped human society… changes involved… nutrition and infectious diseases”(85). Because agriculture allowed people to stay in one place, the authors tell us that diseases spread easier than in nomadic times. This means the authors prove new selective pressures dictated a change in disease resistance. Cochran and Harpending do a very good job support evolution up to early civilization.

However, once civilization becomes more advanced, the authors lack the support they had for more ancient times. The closest the authors have to modern times unfortunately comes 1200 years ago,”The Ashkenazi Jews… began as a community 1200 years ago”(187). The authors go on to explain the Jewish community 1200 years ago kept the traits they had been passed down isolated because of cultural separation. However, this is distinct from evolution; they just had less genetic mixing. The need for proof that evidence is continuing especially in the last 100 years is greater than ever. With new means of globalization, disease prevention, safety concerns, and modern medicine, selective pressures have been greatly decreased. Because issues of obtaining food are no longer a test of competition but a test of where you are born, humans are no longer evolving due to their adaptations but how many resources they have, which is often only passed down to them. This means that there is an ever greater need for the authors to prove that evolution is still continuing. Some may say that the selective pressures have changed to who best operates in a competitive economy. Unfortunately, this is not the case because those from already prosperous families have an advantage over those who may be more productive. In short, the authors fail to prove that humans are evolving to the modern day, which is crucial to them proving their thesis.

The most important quality of a nonfiction book, especially one of scientific background, is to have both accurate and adequate information. Though it is agreeable that the book holds accurate information, it lacks adequate information beyond early civilization. Evolutionary pressures have changed with the invention of modern medicine and therefore more evidence is needed for proof of evolution in the modern age. However, this book does hold enough information to prove evolution in early modern humans adapting language and early civilized peoples adapting to changes in diet. Without addressing the main concerns of evolutionary history in the modern age, the book cannot stand comfortably to the critics of its own theories.