Summary of the book "A Hunter-Gatherer's Guide to the 21st Century" - By Bret Weinstein and Heather Heying

Key Insights in this book:

1. WEIRD persons are raised in an environment that is devoid of natural geometry.
2. There is no such thing as an ideal universal diet for humans.
3. In an unpredictable world, sexual reproduction makes sense.
4. Children must be allowed to explore and discover during their youth in order to evolve into adults.
5. Our bodies' response to a specific condition is sleep.
6. When it comes to health, scientists take a dangerously reductionist approach.

Who can benefit the most from this book:

• Psychology buffs looking for fresh insights.
• Anyone interested in evolutionary biology.
• Fans of natural history

What am I getting out of it? Take pride in your ancestors.

Despite the fact that the modern world has offered us more money and ease than ever before, so many of us are unhappy. Despite our wealth, we are becoming increasingly lonely, unhealthy, and unsatisfied with our lot in life.

How is it possible?

The answer can be found in our ancestors' history. This summary is here to show how our bodies and minds, which have evolved over millions of years, are frequently mismatched with our modern settings. You'll learn why we've evolved the way we have, and how harmful it may be to ignore our evolutionary legacy, from medicine to food to childhood.

• You'll learn how screen time is preventing our children from maturing.
• The evolutionary purpose of sleep.
• And why we reproduce sexually in this summary.

1. WEIRD persons are raised in an environment that is devoid of natural geometry.

Is it possible to detect if two lines written on a page are the same length? You've probably encountered the optical illusion when two lines of equal length with arrowheads at each endpoint in opposite directions. Because of this discrepancy, one line appears to be longer than the other. However, not everyone is fooled by this deception.

People who grow up in hunter-gatherer societies, such as the San Bushmen of Southern Africa, have no trouble identifying the similarities between the two lines. It's nearly impossible for people who grow up in WEIRD countries, which are Western, educated, industrialized, wealthy, and democratic.

The main point here is that WEIRD people grow up in an environment that is devoid of natural geometry.

People in industrialized countries, unlike the San Bushmen, employ sawmills to produce timber with absolutely straight edges and accurate corners. This could explain why humans have problems perceiving differing line lengths: we lose some of our visual capacities when we are prevented from seeing more organic shapes. However, this is merely a theory, and it's concerning that specialists can't state for sure that this is why we battle with illusions like this. But one thing is clear: modernism is eroding our innate capacities in ways we don't completely comprehend, and frequently don't even notice.

Our lack of understanding of how our environment impacts our body reveals itself in a variety of ways. Many people in WEIRD countries, for example, will develop appendicitis, a deadly infection of the appendix. In undeveloped countries, however, appendicitis is a rare occurrence.

Why?

Experts now believe that the appendix serves as a breeding place for the beneficial bacteria and germs that live in our intestines and aid in digestion. A lot of gut bacteria from our digestive tract is pushed out of our body when we have diarrhoea or stomach discomfort. The appendix, on the other hand, does not lose its germs and can therefore grow more to repopulate the tract. People in underdeveloped countries are more likely to be exposed to germs and bacteria than people in WEIRD countries. Our bodies are intended to go through this cycle of stomach discomfort and bacterial renewal in the appendix, even if we think it's a negative thing. We no longer endure frequent stomach problems as a result of our extremely clean and sanitary modern houses, and as a result, our immune systems and gut bacteria become out of balance, resulting in appendicitis in some people.

So, whether it's our immaculately clean homes or the perfectly straight lines that surround us, the contemporary world has an impact on our bodies and minds that we're not paying attention to.

2. There is no such thing as an ideal universal diet for humans.

Which diet is best for you? Many so-called experts claim that we should eat the foods that our forefathers ate. This could include a raw-food diet, which consists solely of uncooked foods, or a paleo approach, which eliminates foods that were unavailable to our forefathers, such as grains and dairy, in favour of meat, fat, and vegetables. But what do our eating habits have to do with evolutionary history?

Here's the main point: There is no such thing as an ideal universal diet for humans.

There have been varied diets for as long as there have been human beings in different parts of the planet.

The Inuit people of Northern Europe, for example, ate and still eat a diet that is extraordinarily high in meat and fat and practically devoid of carbohydrates. This means that, despite the fact that no other people on the planet have a similar culinary legacy, people from this genetic lineage have developed to live on it. Compare the Inuit diet to that of people in the Northern Mediterranean, which has traditionally included a large number of carbohydrates, such as grains. This means that persons of Northern Mediterranean ancestry may benefit from an entirely different diet than people of Inuit ancestry. As a result, we can see how incorrect it is to assume that one single diet could potentially represent what our forefathers ate because our forefathers ate a wide variety of foods.

Let's look at the raw food diet is more detail now. Proponents of this diet argue that avoiding prepared foods is more natural and thus healthier. However, this ignores the enormous advantages that our forefathers reaped from the invention of cooking. When we cook food, for example, we might consume a lot more energy in a shorter amount of time. We'd have to chew raw meals for roughly five hours a day if we didn't prepare them to receive enough energy and nourishment from them if we didn't cook them. That's five hours that could be better spent on something else.

Additionally, cooking allowed our forefathers to detoxify certain plants by removing their harmful properties. In addition, cooking kills harmful germs and parasites in the food. Finally, smoking food helps to prevent deterioration, allowing it to be consumed for extended periods of time. This enabled our forefathers to travel longer distances by allowing them to bring food with them. To put it another way, cooking hasn't held us back; it's been critical to our species' survival.

3. In an unpredictable world, sexual reproduction makes sense.

Human reproduction and sex are both expensive procedures. You must not only discover someone with whom you wish to mate, but you must also persuade that person to mate with you. Your own genes take tremendous damage once you reproduce with another human. After all, if the objective of reproduction is to propagate our genes, it seems inefficient that we only distribute half of them when we mate with someone else.

Wouldn't it be a lot easier if we reproduced asexually like Komodo dragons and some frog species? In that manner, we could eliminate the need for a spouse and convey 100% of our genes to each child we have.

The main point is that in an unpredictable world, sexual reproduction makes sense.

In truth, asexual reproduction is harmful to a species' survival. Only if the world in which you've managed to thrive is expected to remain unchanged would it be advantageous to pass on 100 per cent of your DNA. If it did, your clones would very certainly thrive as well. However, the world does not remain static; it is ever-changing. Bad things can and will happen; a devastating flood, a famine, or a new disease are all possibilities. When you combine your genes with those of another person, you can generate new and beneficial combinations, allowing your children to adapt better to an environment that does not yet exist.

There are several disparities between males and females of the human species as a result of millions of years of evolution.

Sexual dimorphism is the term for these differences. Men and women are at distinct risk of developing diseases such as Alzheimer's and Parkinson's disease, as well as drug addiction and migraines. Men and women have different personality qualities, which is even more disputed. When comparing male and female populations, it is clear that most women are more altruistic, compliant, and trustworthy than men. There is also evidence that men prefer to work with things, whilst women prefer to work with people. Of course, there are plenty of altruistic males who enjoy working with people, but these characteristics will skew females in the general population. The intrinsic disparities between the sexes are evident in the fact that language exists to distinguish between males and females in every single human society that has ever existed. There is no denying that sex is a universal human experience.

4. Children must be allowed to explore and discover during their youth in order to evolve into adults.

Humans have the longest childhoods of any animal, but we're not the only ones who struggle to mature. When a baby orangutan is learning to swing from tree to tree across the forest, he will whimper when he comes to a gap that is too great, and his mother will return to teach him how to cross it. Ravens, too, assemble with other adolescents after leaving their parents and spend years as teenagers together, learning how to connect to one another.

Childhood is, in essence, the period during which we learn about ourselves, how to act, and who or what we might become.

The essential lesson here is that children must be allowed to explore and discover during their youth in order to evolve into adults.

Humans are the closest to being born with a fully clean slate, despite the fact that none of us is. Our brains have the highest flexibility of any species; they are the most pliable. For example, regardless of where we are born in the globe or our ethnicity, we are born with the ability to hear the specific sounds and tones of any language. As we get older, though, we lose our ability to hear language tones and noises that aren't present in our surroundings. Similarly, we are born with more neurons in our brains than we use, and these neurons die off as we grow older, owing to the fact that we haven't used them.

But wouldn't it be preferable to maintain the ability to hear various linguistic sounds, as well as some extra mental capacity?

The truth is that we don't preserve all of this excess capacity because whatever benefit it might provide is negated by the fact that maintaining it costs a lot of energy. As a result, as youngsters, we learn what kind of world we live in and then shape our thoughts accordingly, letting go of abilities that we are unlikely to use.

This is why childhood is such an important time for discovery. As a result, it's sad that many parents in the twenty-first century discourage their children from exploring. Modern parents try to have a tight grip on their children by organizing and planning their time for them; they determine what activities they will participate in and direct them to play in a specific way. Many parents also stifle their children's curiosity about the world by enslaving them to television and other screens. Despite the best intentions of parents, interfering in children's lives like way stops them from developing into fully functional individuals. This is due to the fact that it prevents the developing brain from purifying itself as evolution intended.

5. Our bodies' response to a specific condition is sleep.

Have you ever thought that if you didn't have to sleep, you could do so much more? Almost every other species, like humans, sleeps. Furthermore, if intelligent extraterrestrial life exists elsewhere in the universe, it's quite likely that those aliens require sleep as well. Let's take a look at the evolutionary purpose of sleep to see why.

Here's the main point: Our bodies' response to a specific condition is sleep.

It's a fact that no animal can develop eyes that can see well both during the day and at night. To achieve this level of the dual vision, you'd need two pairs of eyes: one for day and one for night. This would necessitate a considerably larger brain with significantly higher energy requirements than is currently possible. As a result, all animals, including humans, have evolved eyes that specialize in light or darkness. This was their chance to be environmentally conscious and participate in hunting and gathering activities.

With this adaption came a new problem: what to do when your eyes weren't working properly. It was not a good idea for early humans, as well as all other creatures, to be active during this "blind" period since they risked becoming prey to animals that could see. So, rather than being active during this time, it made evolutionary sense to lie dormant in order to conserve crucial energy. As a result, the animals began to slumber.

Understanding why we sleep provides insight into whether or not aliens might sleep. Given that alien living forms would almost certainly experience night-and-day light patterns on their planets, it's only natural that they would participate in some type of sleep.

Sleep's role in humans has evolved over time, despite the fact that it began as a way to alleviate an eyesight problem. Given our formidable brains, it wouldn't make evolutionary sense for them to accomplish nothing when we were sleeping. As a result, we began to daydream. Our brains work through the past and imagine future scenarios when we dream. We put different responses to hypothetical scenarios to the test and process what we've learned that day. So, despite the fact that humans began sleeping before dreaming, our dream state is now critical to our cognition.

6. When it comes to health, scientists take a dangerously reductionist approach.

What is the true remedy for your ailment? In 2009, one of the authors was afflicted with laryngitis on a regular basis. When she went to her doctor, she was told she needed to start taking powerful pharmaceuticals to treat it, as well as other drugs to counteract the side effects of the initial ones.

The author, on the other hand, did not follow his advice or take the drugs because she understood something that many doctors and scientists do not: when it comes to introducing new substances into the human body, the treatment is sometimes worse than the sickness.

The main point is that scientists approach health in a dangerously reductionist manner.

Reductionism occurs when a complex system, such as the human body, is attempted to be reduced to a few measurable pieces. We may now produce medications that are painstakingly tailored to enact a certain physiological change in our bodies in the modern environment. The issue is that our bodies aren't perfectly calibrated. Instead, we're sophisticated beings with intricate communication networks functioning between our minds, hormones, and organs that can't always be fixed by pulling a simple physiological lever.

Reductionism is so harmful in current science because it distributes medications or medical advice that may improve one area of the human body while jeopardizing another.

When scientists learned that fluoride was linked to a lower risk of tooth decay, it was added to public drinking water in a number of countries. However, it's possible that the approach unwittingly created more issues than it solved. Not only does drinking water contain a synthetic type of fluoride, but it also has the potential to create neurological issues in children, and there is a link between drinking fluoridated water and hypothyroidism. This emphasizes an important evolutionary point: there are relatively few magic bullets when it comes to the human body. Fluoride may appear to be a cure-all, but it isn't.

The world of processed food is another example of reductionism in science. We can now successfully increase the shelf life of a variety of food goods by adding a chemical called propionic acid, which inhibits mould growth. However, propionic acid has been linked to greater incidences of autism in children who have been exposed to it. It affects the brain development of fetuses in the womb. Once again, that handy magic bullet is nothing more than a ruse.

The essential takeaway from this summary is that evolutionary biology is rife with trade-offs. We can't enjoy something's benefits without paying a price somewhere else. However, in modern life, we frequently overlook these trade-offs, assuming that the conveniences, medicine, and technologies that surround us are all beneficial. This underlying misunderstanding has resulted in health issues and concerns about children's normal development into adults.

Advice that can be implemented:

Feel the earth beneath your feet with your bare feet.

According to the current world, we need a distinct pair of shoes for each event. However, sometimes the best thing to do is to go barefoot and not wear any shoes at all. Because of the calluses that form on the soles of our feet over time, evolution has equipped us with natural shoes. When you don't wear shoes, your feet can communicate a lot more information about the type of terrain you're standing on, allowing you to move as efficiently as possible.