How do humans domesticate themselves?

BEIJING, Nov. 6 (Xinhua) — In 1959, Dmitri Belyayev, a Soviet zoologist and geneticist, traveled to Siberia in search of the “most polite” fox he could find. Belyayev was interested in how domestication of animals occurred and how the biological characteristics of wild canines evolved into mild-mannered dogs. In the Siberian countryside, there are thousands of fox-skin farms, ideal for his experiments.

Belyayev began to breed particularly docile foxes and observe the temperament of his cubs. In just three generations, these foxes have significantly reduced their fear and aggressiveness to humans. By the fourth generation, some cubs will even wag their tails like retrievers to catchers. The animals showed friendly signs to humans that they had been domesticated.

Brian Hare, an anthropologist at Duke University in the US, argues that humans have inadvertently gone through similar processes in their evolutionary history, making us more cooperative than the extinct Neanderthals and Denisovans.

Although Belyayev’s foxes have undergone the evolution of artificial breeding, Brian Hale and others believe that in Homo sapiens, natural selection tends to favour friendly temperaments. In other words, without realizing this, humans domesticate themselves in their own evolution, a more easy-going manner and attitude that has contributed to our success on Earth and has continued to breed to this day.

In his new book, Survival of the Friendliest: Understanding Our Origins and Rediscovering Our Common Humanity, Brian Hale asks the question: Why are people who are more likely to work with those around them, more willing to compromise, and more likely to survive? Violence and aggression, he writes, are not always a reasonable evolutionary strategy. Being a leader in a group means getting involved more often in dangerous situations and being a target for a larger group;

“When you look back at nature and you see that when a species or species underwent a major transformation or succeeded in a new way, the increase in friendship or cooperation is usually part of the story,” says Brian Hale. He cites the evolution of flowering plants, or beech plants, which evolved 100 million years ago in collaboration with pollinators. As the first domesticated animals, dogs were also more adaptable because they were friendly – human-friendly wolves had more reliable sources of food and better chances of survival.

An important milestone for humanity is the cognitive revolution that took place between 40,000 and 90,000 years ago. At that time, human creativity burst out, and a large number of tools, weapons, carvings and cave paintings emerged. Cooperation means that skills and knowledge can spread at an unprecedented rate within groups of human ancestors who hunt and gather for a living, as well as between groups.

Domestication syndrome

Previously, the idea of human self-domestication has repeatedly caused dissatisfaction among scientists. Some claim that human self-domestication has brought us down to the same level as other species, making us as vulnerable and dependent as other domesticated animals. Darwin observed that there were certain common characteristics between domesticated animals of different species. For example, home animals tend to have softer ears and rolled tails than wild animals; Domestication also narrows the brain’s fear center, the amygdala, reducing aggressiveness and fear responses.

Belyayev noted that his domesticated fox eventually developed black-and-white spots, a trait now considered a classic symbol of domestication. Think of the black-and-white cows, horses, dogs, and cats – especially the all-white black cats (known as “dark clouds and snow”).

The problem is that these characteristics have no effect at all other than meek. The Belyayev study, and other similar studies, show that if you choose friendly and cooperative foxes, you get a whole host of other traits that don’t work. From an evolutionary point of view, these characteristics are non-adaptive, just like men’s nipples. The researchers collectively refer to these characteristics as “domestication syndrome”.

Over the years, scientists have realized that domestication seems to retain the psychological and physiological tendencies of larvae, especially those that cause concern to parents and other adult individuals, such as “cute”, a little helpless, and human-friendly. All this supports Brian Hale’s argument. Recent scientific research has cobbled together the reasons for this.

During the development of vertebrates, there is a short band of cells at the back of the embryo called a “nerve crucible”. As the fetus grows in the womb, these cells migrate through the body, helping to form cartilage and bones on our faces and chins; Nerve cells also form our adrenal myelin. The adrenal glands release cortisol – our “stress hormone” – and adrenaline to participate in our fights or escape reactions.

Home animals have smaller adrenal glands. According to Brian Hale, friendly choices reduce neurotic migration, and therefore less aggressive and reactive behavior driven by adrenal hormones.

However, the decrease in nerve cells reaching their intended targets also affects other characteristics that drive them in the body, which explains why the noses and chins of home animals are smaller, and there is a lack of melanin in white fur. Scientists already know that domestication, whether artificial or natural, seems to involve the selection of a gene called BAZ1B, which helps drive neural crucible migration during development.

In recent years, the most frequent reference to the theory of self-domestication has been richard Langham, an anthropologist at Harvard University. He was a graduate tutor to Brian Hale, and the two worked together for a long time to study how certain species were domesticated, including foxes that traveled to Siberia to study Belyayev (although Belyayev died in 1985, his experiments continued 60 years later).

In the late 1990s, the work of Lyudmila Trut, Belyayev’s longtime collaborator, made Richard Langham think that the story of siberian foxes might have inspired the domestication of primates, especially bonobos.

How do humans domesticate themselves?

Bonobos and chimpanzees are the closest animals to human relations. However, chimpanzees are usually violent, while bonobos live more peacefully, with females in control of social power. Like humans, male bonobos are violent, but females unite to control overly aggressive males. Unlike chimpanzees, bonobos do not kill members of their species. They also have a lot of sex, which earns them a reputation for “free love.”

“I’m starting to think that in bonobos, self-domestication is the best way to choose to fight aggression,” says Richard Langham. “He and Brian Hale agree that the differences in temperament between chimpanzees and bonobos come from where they live.

Chimpanzees have evolved in some of Africa’s more food-deprived regions, where they have had to compete with gorillas for the prize. The evolution of bonobos is in the rich Congo Basin. Brian Hale explains that while authoritarianism and aggression have evolutionary advantages in difficult times, the hierarchy in which only a small number of people in a group can gain access to most of their resources and reproductive opportunities can be extremely expensive. Data on chimpanzees and moths show this.

If, for some reason, the population has a new resource available, or if the resource becomes abundant, aggression no longer has an advantage.

Based on his study of bonobos, Richard Langham went a step further and applied the same theory to humans. “I’ve come to realize that there are some similar characteristics between bonobos and humans, so human self-domestication has a fascinating possibility, ” he said. “

The study found that it was often the friendliest male bonobos who succeeded in the group. Brian Hale argues that humans and bonobos have a similar past, and that in our evolution, the new ecosystem – perhaps finding ourselves in a region richer in fruit and animals – has changed the way we interact with society and facilitate cooperation.

A friend in good errity

Indeed, humans are more cooperative than most other species. But how should human beings view their ability to commit atrocities such as murder, genocide and slavery?

As we become more social and cooperative, we begin to strongly identify with our communities. In this way, we are more suspicious of others, anyone outside our family and friends circle.

“There are two ways to form a group,” says Emiliano Bruner, a paleontologist at Spain’s National Centre for Human Evolution. Another approach is to emphasize differences with another group. Both strategies work, but in the first case, you bet on love, which is often difficult because it requires accepting the differences between us. In the second case, you bet on hate, which unfortunately is much easier! “

As psychologists say, self-domestication brings cohesion to the inner circle of humanity – we are more connected to our own inner circle. But at the same time, it has led to a deeper level of xenophobia. “Humans often form alliances in the name of ideology, gender, race, political differences, or anything that can be found, and hate certain people,” Brunner said. Individuals need to feel that they belong to a group and that they are prepared to do anything stupid to enter it. As a result, humans are often afraid of loneliness. “

Prejudice is toxic, and sadly, humans are often trapped in it. But according to Brian Hale, our desire to harm and exploit other members of humanity is rooted in deeper hearts, not just in dislike of them. On the contrary, this is because they were not treated as human beings in the first place.

The ability to “dehumanize” is perhaps The Darkest quality of Homo homo homo des Homos. We instinctively make ourselves invisible to those we fear, or the humanity of those we can exploit. Brian Hale cites neuroscience research that supports his view that “there is a network in the brain that may inhibit consortity, so that we no longer calculate what people who threaten their groups are thinking – you don’t necessarily think of those people as complete human beings,” he speculates. “

If this theory holds, it could explain why war, slavery and other human atrocities began to emerge in an increasingly cooperative civilization after the agricultural revolution some 11,000 years ago.

Brian Hale argues that if prejudice is used to explain the ills of human society, we may focus on the wrong issues. If psychologists, neuroscientistes, politicians, etc. try to use brain mechanisms to explain the lack of human nature, the probability of success may be greater. Doing so, he argues, could even help ease America’s suffocating political polarization.

Instead of inventing the concept of human self-domestication on his own, Brian Hale was based on Richard Langham and other scholars in the field. However, Langham recalls, Hale’s work (including studies of Siberian foxes, dogs and bonobos) provided a wealth of arguments that friendly human psychology was the result of natural selection, that we were more friendly to familiar people and more aggressive to people outside our circle. (Any day)