WE’RE LOSING IT!

If you don’t use it, you lose it – and we’ve been losing it for thousands of years.

Yuval Harari, historian, professor, and author explains how we got to where we are today in the New York Times best-seller “Sapiens: A Brief History of Human Kind” .  About 2 million years ago, there were prehistoric humans that were no more impressive than other species. From 2 million years ago until about 10,000 years ago, there were a number of human species. About 70,000 years ago, Sapiens underwent a “cognitive revolution”, where their brains evolved to become much larger, and they were the only species capable of large-scale communication and cooperation. Along with the expanding brains came communication, which allowed for knowledge sharing, collective group learning, and the passing of information across generations. Language and social hierarchy, then later religion and economics exponentially grew collective abilities of Sapiens.  This was what took homo sapiens from the middle of the food chain about 400,000 years ago, to the top of the food chain 100,000 years ago, then exited the food chain about 12,000 years ago, then to total world domination for the past 1000 years.

Evolution is change in the heritable characteristics of biological populations over successive generations. It is about the passing on of traits (genes) to your offspring, then to their offspring, and so on. The traits that favor successful reproduction are passed on, while the traits of those who don’t survive long enough are lost. For an extreme example – If there was a gene that gave birds only 1 wing, their chances of survival would be very poor. They would struggle to flee from predators and wouldn’t be good at catching bugs for dinner. The 1-winged birds likely wouldn’t live long enough to reproduce and pass on the 1-wing gene (sounds like a band name).  Now, some of those birds would survive long enough to reproduce. Perhaps a few 1-winged birds happened to also have razor-sharp teeth. These birds could ward off predators and find a new source of food. Now these 1-winged razor-toothed birds would be able to produce and pass on their own genes but at a different success rate. Over several generations, there would be varying amounts of 2-winged birds, 1-winged birds, and 1-winged razor-toothed birds. Once again, this is a very dramatic example. It may seem like a simple equation, but considering that humans have 20,000-25,000 genes which determine their biology, and every other species has many genes, and many species interact with many species, and the habitat/climate is always changing, and catastrophic events happen that throw a wrench in things, it can get very messy. As well, many populations of species hold millions of their kind, and some species are not fertile for decades. So, change across an entire species is incredibly slow. Often, we are talking millions of years slow. The evolution of a species can cause a divergence, a gradual evolution of a new species out of another species. You can visualize an evolutionary tree as a stream of water, splitting and meandering around rocks. Evolution is a very complex, dynamic, ongoing process that is only visible when you look from far enough away.

For the past almost 2 million years, we slowly evolved to become more proficient hunter-gatherers. Individually, we were weak and slow, but we could cooperate in groups and travel great distances. We were the ultimate endurance animals. Evidence shows that some hunter-gatherers would run the equivalent of 2 marathons… in one day! We were built for it. Although we were slow, it was way more energy efficient to run on two legs. The upright posture reduced the body surface area exposed to the sun directly. Our now hairless bodies and sweat glands helped us keep cool, while other animals didn’t have sweat glands and had to pant to keep cool. Panting is an incredibly inefficient way to cool yourself down, leading to quick fatigue and exhaustion. Sapiens were persistence hunters, chasing animals until they collapsed to the ground exhausted, then harvest it and bring it home. We would work very well together to hunt down much larger animals and share our success with the group. We were also nesting mammals. We had a place to call home that we left all day to hunt and gather, then return to. We would nest and raise young in groups. Being social and working as a team was one of our secrets to evolutionary success. 

We started refining tools, making fire, advancing communication and developing culture. Our physical features changed, and our brains grew. Just a short 12,000 years ago began the transition into the agricultural revolution. 

To put this into perspective – 12,000 years makes up 0.0006% of the time humans have existed. Evolution occurs over millions of years, but just in the last 12,000 years, our lifestyle demands have changed drastically. Just yesterday we were figuring out how to grow our own food, and now we are riding hoverboards and shipping people off the planet in rocket ships!

During the Neolithic revolution (the first agricultural revolution) we began domesticating animals and farming crops. This meant we no longer had to leave our nesting areas to find food and resources. It was a gradual transition, but being cognitively advanced creatures, we learned quickly. We rapidly advanced our techniques and expanded our resources to become more efficient farmers. Although it created a more abundant food supply, the food was of poor nutritional value and we were tasked with repetitive labour. We went from traveling the distance of 2 marathons in a day chasing antelope, to plowing fields and working on a confined area of land. A body optimized over 100s of thousands of years for persistence hunting will not thrive in an environment of repetitive heavy moving. The earliest evidence of musculoskeletal disorders such as degenerative joint disease and disc herniations dates back to as early as the dawn of the agricultural era. 

“Our environment has changed so rapidly; evolution cannot keep up with the new demands of our self-made environment.”

As hunter-gatherers, we also gathered foods such as nuts, fruits, and seeds. These types of foods high in salt, fats, and sugar were a rare treat to come by. The genetics of Homo Sapiens evolved to crave food high in salt, fat, and sugar because of the scarcity of this rich energy source. You see, while evolution was a sex game, survival was an energy game. It takes energy (activity) to get energy (food), without turning into someone else’s energy, The reward for survival? Reproduction; and the passing on of your genes to your offspring to contribute to the evolution of a more successful species. This food craving would drive sapiens to eat as much salt, fat, and sugar as possible, when possible. Between the other hominids and apes, there was a lot of competition for these foods. If a Sapien came across a fig tree, they would stuff their faces before someone else crashed their party. It was too risky trying to fight others off. Our genetics haven’t changed, but our availability of food has changed dramatically. We are now able to sit in a car, drive up to a window, and be served a bag of salt, fat, and sugar, super-sized! Not only can we get these energy-rich foods anytime, but we also don’t have to expend any energy to get it. After the dawn of the agricultural revolution, we experienced a huge increase in diseases like Type II Diabetes, Cardiovascular Disease, cancer, dental cavities, ocular disease, and many more. Think about that next time you order delivery and think about dessert.

Since the dawn of the agricultural revolution, things haven’t slowed down. About 200 years ago we entered the industrial revolution, transitioning to new manufacturing methods for mass production. Only 40ish years ago, we entered the digital age, transitioning again to an economy based upon information technology. As time has gone on, our living conditions have changed more and more rapidly, to the point where the world changes significantly in just one person’s life. My grandmother (who I call Oma) tells me stories of World War II, while I share my stories with her from my smartphone. 

How come evolution hasn’t been on our side? Because evolution is a sex-addict. It passes on genes across generation to improve the success of survival to re-productive age. We are becoming less and less healthy because as a species, we have managed to maintain success. The 7.8 billion people on this planet is living proof. Our life expectancy has gone up some since our hunter-gather days, but our years of quality life have gone down. Our advancements in medicine and healthcare have helped us to live longer, but these extra years are spent sick and suffering (on average). We are living longer but we are living sicker.