Robert Sapolsky. Who Are We? Part 1 - Research, Reviews, Society

• Robert Sapolsky
• Who are we? Genes, our body, society
• M.: Alpina non-fiction, 2018

Robert Sapolsky is a renowned neuroscientist, professor at Stanford University, popularizer of science. To the book Who Are We? includes the best articles of the scientist about man in all his amazing diversity. Its three sections are devoted to the main issues of natural science, including the influence of genes and environment on behavior, the social, political and sexual prerequisites of behavioral biology and the role of society in personality formation.

In everything Sapolsky describes - from the mating rituals of rodents to the religious practices of rainforest dwellers, from the release of pheromones to brain parasites - he brilliantly combines cutting-edge scientific discoveries with ironic and wise observations about the unimaginable complexity of life

• How do subtle environmental changes affect our behavior?
• What is the anatomy of a bad mood?
• How does stress affect our brain?

A world-renowned scientist answers these questions in an accessible and fun way, with lively and vivid examples

Do you love urban legends, these unheard of stories that everyone believes? Some researchers make a living by studying urban legends: they compile catalogs, trace their sources in Scandinavian mythology, argue about them at conferences. But in the midst of all this intellectualization, some of the stories people buy into are simply amazing. They talk endlessly about a man who put a poodle in the microwave to dry it, or about a scuba diver who was scooped up by a fire plane along with water and then thrown onto a forest fire. They also talk about a woman who left her purchases in the car in the heat, and just when she returned, a package of dough exploded and splattered on the back of her head: and the woman was sure that she had been shot, and the dough was bits of her brain. And then there is the myth of a group of scientists who sequenced the human genome:they can explain everything about you, just look at the sequence of your genes.

Of course, someone's cousin is friends with someone whose uncle swore that he could explain everything because he helped to sequence the human genome. But this is not so: we are returning to the realm of urban legends. Why are people so clinging to the idea that genes are everything? Now it is especially obvious that this is a delusion. Recently, not only have the human genome been (almost) sequenced, but also celebrated the golden anniversary of the discovery of the structure of DNA. The celebrations were rife with religious imagery of the genetic code as a sacred relic, the Code of Codes. Even biologists - people who are paid to know better about the subject - support these sentiments. This is surprising, because genes do not control anything by themselves. We return to the sphere of interaction between genes and the environment - these are the words that a novice biologist first utters. The concept of the interaction of genes and the environment can be interpreted in different ways. But at least this means that people who prove the priority of nature in relation to education are at least a century behind. More precisely, this means that genes can (indirectly) give instructions to cells, organs and organisms how to function in the environment, and the environment can regulate the activity of genes at one time or another. But most importantly, the direct product of a particular gene - a particular protein - works differently in different environments. So, in theory, you have a gene that will grow antlers in one environment and make you fly south in the winter in another.that genes can (indirectly) give instructions to cells, organs and organisms how to function in the environment, and the environment can regulate the activity of genes at one time or another. But most importantly, the direct product of a particular gene - a particular protein - works differently in different environments. So, in theory, you have a gene that will grow antlers in one environment and make you fly south in the winter in another.that genes can (indirectly) give instructions to cells, organs and organisms how to function in the environment, and the environment can regulate the activity of genes at one time or another. But most importantly, the direct product of a particular gene - a particular protein - works differently in different environments. So, in theory, you have a gene that will grow antlers in one environment and make you fly south in the winter in another.

For those still fighting in nature / nurture wars, the question is now: Okay, how strong are these interactions of genes with the environment? At one extreme are those who ridicule the juxtaposition of horns and flights to the south. From their point of view, the gene does either one or the other, and the environment can only change the speed, strength or duration of the effect. But no environmental influences can radically change the manifestations of the gene. This is akin to the idea that the wind can change the speed of an anvil falling from the tenth floor onto your feet, but who cares about this interaction of the anvil with the environment? And those at the other pole argue that interactions can have enormous consequences - say, an environmental factor like wind can cause the impact of an anvil to fall no stronger than that of a feather. So scientists happily argue and experiment, squandering taxpayers' money that could have gone to oil contracts.

In the course of these debates, it is helpful to keep in mind how powerful interactions between genes and environment can be. And three recent studies provide excellent examples. The first concerns the effects of the most imperceptible, underestimated environment - the intrauterine environment. Were bred lines of laboratory rodents with different characteristics: one line - a certain type of diabetes, the other - hypertension, etc. Each line is the result of closely related crossbreeding in many generations, animals become genetically almost identical - like clones of each other. If all animals of this line, regardless of the laboratory in which they grew up, show a certain trait, then you may have fallen on the trail of a strong genetic influence. After inbreeding, a crucial experiment is conducted known as the cross-rearing method. Supposeall line A mice prefer Coca-Cola, and line B mice prefer Pepsi. Take a few mice from line A at birth and give them to mothers in a colony of line B.

But how relevant is cross-training research? And here comes the new study by neuroscientist Darlene Francis and colleagues at Emory University, published in the prestigious journal Nature Neuroscience. They studied two strains of mice with differences in behavior. To simplify, let's say that one line was more anxious and fearful. Compared to the "calm" line, the "fearful" mice were slower to adapt to the new environment and were less successful in learning under stress conditions. Mouse geneticists have known these differences for a long time. They also confirmed that the differences are largely due to genetics. Indeed, some data have shown that mothers of the “calm” line are more caring than the “fearful” ones - they lick and clean the cubs more. These data allowed for an unpleasant opportunity for the "gene camp"that the differences between the lines are caused by the type of motherhood. But then they conducted a decisive test - mice of the "calm" line, which from the very birth were brought up by "fearful" mothers, grew up as calm as any mouse of their line.

Team Francis went one step further. Using in vitro fertilization technologies, they transplanted fertilized eggs from calm line mice into the “fearful” mice that were carrying them. The control group of "calm" mice was transplanted with "calm" embryos - in case the very procedure of artificial insemination and implantation affects the result. After birth, some cubs of the "calm" line were raised by "fearful" mothers, and some by "calm" mothers. What was discovered? When mice, in theory genetically “calm”, developed both in the womb and in infancy in “fearful” mothers, they grew up as “fearful” as other mice of the “fearful” line. Same genes, different environment, different result.

This raises two questions. First, environmental influences don't start at birth. A factor or more of a “fearful” mother's environment during pregnancy - stress levels or nutrition - affect her children's anxiety and learning abilities, even as adults. These mechanisms may be associated with changes in brain structure, hormonal profile, or metabolism. Actually, some of these effects of intrauterine development have already been described for humans. Second question? Calm line mice are calm not only because of their genes: the environment of their intrauterine and infant development is the most important factor.

It must sound disappointing to those who stand up the mountain behind the urban legend of the power of genes.

Beware of oversimplified explanations - nature rarely gives clear answers. And store your genes in a designated place

Sometimes genetics speaks of inevitability: for example, if you have the gene for Huntington's disease, then by middle age you are 100% likely to develop this terrible neurological disease. But more often than most people think, genes mean both weaknesses and opportunities, not predestination. It follows from this fact how important the role of society is: genes do play a role in the fact that we behave in undesirable ways. But our knowledge of these genes teaches us that we are all the more responsible for creating an environment in which interaction with these genes will be favorable.