My rating: 5 of 5 stars
It should be stated from the outset that this is not a 'self-help' book, but it definitely does raise awareness of some aspects of our modern lives which are silently and steadily harming us. Lieberman recognized the root of many of the common chronic non-infectious diseases to be evolutionary in nature, specifically ‘evolutionary mismatches’. He persuasively argues that our bodies which are molded and shaped by the adaptive force of natural selection over millions of years are no match for the abrupt changes brought about by our rapid cultural evolution.
Think of reading these very words. Evolutionary speaking, it is really weird that a bipedal primate spends hours upon hours seating on a chair, and fixating her eyes on a monotonous black and white pattern. This is just one of many examples of how so much of our mundane activities are in fact quite bizarre, given what we know about human evolution. Undoubtedly, the propensity for adaptive behaviour is one of the hallmarks of our species. It has given us a tremendous selective edge to be creative and resourceful in manipulating our environment to our benefit. Lieberman doesn’t deny this fact. However, he believes the extent of which we have changed our environment over just few centuries, or indeed the last few decades is unprecedented by any prior technological innovation. In other words, even though we are a highly resilient and adaptable species, maybe this time, the changes are just too much.
What’s the solution? Throwing away all the comfy technological advances and returning back to the good ol' hunting and gathering? Certainly not! That would be foolish. But, also treating our bodies as if they have changed profoundly since the time we were hunter gatherers is foolish. To be sure, we have changed since then, as it’s evident in some local populations that can break down lactose right into adulthood. Unfortunately, evolution has not had enough time to deal with many accelerated novel cultural changes. Think of the copious amount of sugar, abundant processed foods, comfortable sneakers, eyeglasses, elevators, cars, chairs, air conditioning, and super markets. We are living our lives in an unnaturally prolonged positive energy balance. Meaning, we eat more, while doing less.
The author is nothing if not unambitious! Even after we are armed with all these knowledge, we still want that damn donut, don’t we?! Experiments repeatedly reveal that children and adults instinctively prefer foods that we evolved to crave (sweet, starchy, salty and fatty). Also, factors like advertising and peer pressure strongly affect our decisions. The last chapter’s focus is on this problem. What do we do with this knowledge? How do we change things for the better? The author recommends changing the environment itself as the most effectual solution. Humans sometimes need to be encouraged and even obliged to act in their own best interest. Take, for example, smoking. Of course adults have free will, but in the recent decades we have finally recognized it as a public health issue. For example, we have regulations prohibiting sale to minors. The same kind of logic can be applied to the food industry and maybe even to physical education.
In the end, we can’t eliminate all the risk factors and live completely tuned in to our evolutionary heritage. Even if we did, evolution’s job is not to keep us in maximum health anyway. We probably should find a middle ground between living an austere simple life of our ancestors, and a soft indulgent technically enhanced life.