About the selfishness of our genes
The origins of altruism and cooperation
Alexander Klochko, "Science and Technology"
Altruism and cooperation are two terms underlying any moral and ethical code, all religious teachings and the foundations of human humanism. But these concepts, which are traditionally identified exclusively with humans, are in fact inherent in the entire living world, up to unicellular. Biologists have been engaged in research on the "evolution of the soul" of man relatively recently, before that, philosophers and clergymen were engaged in emerging issues. There was a kind of ban on the study of man in the natural science framework. If some people eventually came to terms with the animal nature of our body, then no one wanted to recognize the animality of our "soul", discarding the divine principle of the Homo sapiens species. But for a biologist, altruism implies the behavior of an individual aimed at the reproductive success and survival of another individual to his own detriment. Cooperation, on the other hand, should include a kind of altruism, unification to solve the tasks set by life, where everyone has to sacrifice something.
It is not difficult for an unbiased observer to notice altruism in the animal world. Often the mother bird pretends to be a wounded one in order to distract the predator from the nest. An ant infected with a fungus, feeling an imminent death, leaves the anthill, saving its relatives from a similar fate. The bitch feeds other people's puppies.
Where did altruism come from in nature, if the basis of natural selection is selfishness aimed at the survival of an individual at any cost? After all, where the strongest survives, there is no place for altruism. "In one sitting, the strong will eat the weak," is a primitive idea of the selection of the times of Darwin's bearded meetings on the Galapagos Islands. For all living things, selection exists at different levels – at the level of species, populations, groups, individuals and genes. They should not be mixed, it should be remembered that the selection results will be recorded only at the gene level. Therefore, the main level that is worth paying attention to will be the level of genes. There is no place for altruism anymore. If an "altruist gene" appears in the gene pool, then it will inevitably disappear. Genes are inherently very selfish, but the interests of an individual gene may often not coincide with the interests of a particular individual for survival. The organism carries one or two copies of these genes, while the genes themselves are present in the gene pool with many copies. It is often advantageous for a gene to sacrifice several copies, forcing them to commit an act of altruism, in order to provide an advantage to the rest of its copies in other organisms.
The Englishman Richard Dawkins highlighted this topic most vividly in his book "The Selfish Gene", published in 1976 and has undergone three reprints. "You can look at natural selection from two different points of view," Dawkins says, "from the point of view of the gene and from the point of view of the individual. If understood correctly, they are equivalent; they are two views of the same truth. You can jump from one to the other, but it will still be the same neo-Darwinism.
"Man and all other animals are machines created by genes. Like the lucky Chicago gangsters, our genes have managed to survive in a world where fierce competition reigns. This gives us the right to expect certain qualities in our genes. I argue that the predominant quality of a successful gene should be ruthless selfishness. Gene egoism usually gives rise to selfishness in the behavior of an individual. However, as we will see later, under certain special circumstances, the gene is best able to achieve its own selfish goals by encouraging a limited form of altruism at the level of individual animals."
Dawkins' book is controversial in many ways, and discussions around it do not subside to this day, but it certainly gave a powerful impetus to the development of scientific thought. Although it can hardly be called revolutionary in the full sense of the word. Earlier in evolutionary biology, the idea of kin selection, or Kin selection, was already developed. The English scientist John Haldane most accurately expressed the essence of kin selection, saying once: "I would give my life for two brothers or eight cousins."
The essence is very simple: we are ready to sacrifice ourselves for the sake of preserving our genes in other individuals – relatives and children.
William Hamilton, the luminary of the theory of kin selection, deduced the rule that students of kin selection rely on to this day.
Hamilton's rule
The "altruism gene" will be supported by selection if
gW > C
where r is the degree of genetic relationship of the "donator" and the "accepting victim"
C – the reproductive advantage received by the addressee of the act of altruism.
C is the reproductive damage caused by the altruist to himself.
Reproductive advantage can be measured by the number of descendants left.
If the act of altruism has several recipients, then we add n – the number of recipients of the victim.
nrB > C
There is nothing unusual in Hamilton's rule, everything rests on the basics of population genetics.
The best example of the work of Hamilton's rule can serve as hymenoptera. Here is the triumph of altruism and cooperation. They sacrificed their reproductive potential, giving it to the queen queen, and they collectively work for the benefit of the colony. But this altruism is far from disinterested. Kin selection is not enough to justify the refusal of workers to lay eggs.
An interesting experiment was conducted on wasps of the species Liostenogaster flavolineata. These insects live in a group of an average of ten individuals with one queen queen, whose offspring are all taken care of together. When the queen dies, the second oldest female takes her place. At the same time, the level and duration of its life becomes noticeably higher than that of the worker wasps, who have to get food for the colony, constantly risking being eaten.
Scientists have revealed an interesting pattern: the less chance a working wasp has of becoming a queen, the harder she works to pass on her genes even through other people's children. The first female in the queue for the place of the uterus will often sit out in order to reduce the risks and simply not wear out the body.
Entomologists transplanted the females second in the hierarchy after the queen to the hives, where they occupied the last place, after which the wasps who had once been shirking from work began to work actively. And in the same way, the last in the hierarchy of wasps were transplanted into hives, where they occupied the first place after the queen, after which they began to show less enthusiasm for work. Thus, those who have nothing to lose sacrifice the most.
A group of entomologists from Germany conducted a series of experiments on various hymenoptera, during which they tried to find out which factor influences altruism in insects more – kin selection or "morality police", in other words, the suppression of acts of selfishness.
During the observations, it turned out that the strictness of the "supervision" of the tested insects directly depends on the frequency of acts of selfishness. It also turned out that there is a dependence on the degree of insect kinship (ideally, this is 75% of the common genes), since the uterus can mate with several males. The lower the degree of kinship, the stronger the supervision, and acts of selfishness become rare. This is not a direct consequence of kin selection, but a method of combating deceivers who are not averse to taking advantage of the altruism of others. So, often under the guise of "their own" larvae of babbler flies can live in an anthill, feeding on brood or carrion. Females lay eggs near the anthill, and then, using chemical mimicry, the larva penetrates inside. Or princesses from other colonies settle in an anthill and begin to lay their eggs.
Deception is a social parasitism in which the egoist enjoys the fruits of cooperation and altruism of others. How does this factor influence the evolution of altruism? These two modes of being have always gone hand in hand. Interestingly, this phenomenon fully manifests itself already at the level of unicellular. This is perfectly evident from the example of studying the bacterium Pseudomonas fluorescens, which is rapidly evolving right before the eyes of researchers, mastering new niches and developing original adaptations.
In a liquid nutrient medium, bacteria develop first as single, mobile cells and gradually occupy the entire thickness of the broth. At this stage, oxygen deficiency occurs in the environment, and then some mutations are in demand. In particular, mutants that secrete substances that promote cell bonding gain an advantage. Such bacteria after division cannot "peel off" from each other and form a film on the surface of the medium. While single cells float in the thickness of the broth, the glued ones "capture" the surface, where there is much more oxygen. Glue production is expensive, but the total reward (oxygen) more than covers the costs. This is a real evolutionary breakthrough. It would seem that the emergence of a real multicellular organism is not so far away. But, alas, the success of Pseudomonas fluorescens specifically in this direction is very limited. Their colonies are short-lived because they are completely defenseless against the "deceiving" microbes that begin to parasitize this colony. The problem is that natural selection is most favorable to "deceiver" cells, that is, mutants who stop producing glue, but continue to enjoy the benefits of living in a group. There are no mechanisms in this system that would prevent such cheating. Impunity contributes to the rapid reproduction of deceivers, which leads to the destruction of the colony and the return of the bacterial population to its original state.
Any social system in which the actions of deceivers are not suppressed is doomed to collapse. Therefore, cooperators develop ways to identify and eliminate selfish deceivers so that cooperation is not meaningless. Selfish deceivers, in turn, develop ways to hide and continue to freeload. A kind of "arms race" begins, stimulating the development of both sides.
An example of the work of the Simpson paradox with respect to the problem we are interested in is as follows.
Deception should be as statistically justified as altruism. Imagine a city of liars, where everyone lies to each other, no one believes anyone – any communication and cooperation is impossible here. A certain number of liars will still be able to comfortably exist, continuing to deceive everyone, but only until cooperation disappears completely. At the same time, it turns out that the more cooperators there are, the less profitable it is to be them. Then why don't altruists disappear from the face of the earth? It is obvious that the altruistic strategy allows the body to occupy the maximum number of ecological niches and master the resources there. The existence of altruists is possible due to the fact that the total share of goods produced by altruists is higher than that produced by egoists. Here we are dealing with the so-called Simpson's paradox. In its most generalized form, it is a phenomenon in statistics when, in the presence of several data groups, each of which has an equally directed dependence, when these groups are combined, the direction of dependence changes to the opposite.
There are an equal number of altruists and egoists in the global population. We divide the global population into three subpopulations with a different ratio of egoists and altruists. In the course of the growth of all three subpopulations, altruists are the losers – the percentage drops in all three cases. However, the subpopulation where there were initially more altruists grew stronger, as it had more productivity due to the cooperation of altruists. If we add all three subpopulations into one global one, we will get an increased percentage of altruists.
Back in the middle of the last century, scientists spoke about the possibility of such a mechanism, but recently it was possible to experimentally prove the Simpson paradox.
In order to find out whether Simpson's paradox can really ensure the prosperity of altruists, American microbiologists have created a living model of two genetically modified strains of E. coli.
The "altruists" were sewn a gene responsible for the synthesis of a signaling substance to communicate with each other. A gene synthesizing an enzyme for resistance to the antibiotic levomycetin and activated only in case of contact with the signaling substance from the outside was added to the genome of both strains.
The "egoists" were distinguished by their inability to synthesize a signaling substance. There were no more differences between these strains. It turns out that the signal substance is necessary for both strains of the bacillus in the presence of an antibiotic. The benefits of the signaling substance for both strains are the same, only "altruists" need to spend money on synthesis, and "egoists" do not need to spend money.
Both strains are artificially bred, so there are no pitfalls in the relationship between "altruists" and "egoists".
As expected, in an environment with an antibiotic, pure cultures of "egoists" grew worse. In an environment with "altruists", "egoists" began to grow better than the "altruists" themselves.
The sticks were planted in 12 test tubes, in the medium of which the antibiotic was contained, the strains were in the following proportions: 0, 10, 20, 30, 40, 50, 60, 70, 80, 90 and 100% "altruists", respectively. After a control time, the scientists measured the number of bacteria and the percentage of "altruists" in each of the test tubes. It turned out that in all test tubes, the relative number of "altruists" decreased significantly, except for the first and twelfth. However, the size of the population where there were initially more "altruists" has grown significantly more than where "egoists" prevailed. When microbiologists summed up the number of sticks from all the test tubes, it turned out that the overall percentage of "altruists" had increased markedly.
This works when the population is artificially divided into test tubes. This can also work in natural conditions, especially when the so–called "bottleneck effect" comes into play - a period of population decline with its recovery in the future. For example, when the substrate is populated with new microbes-colonizers, which by chance may include the percentage of "altruists" necessary for growth, while colonizers with a large content of "egoists" will slow down in growth. Simpson's paradox will ensure the "global" growth of the population of "altruists" in the aggregate, from all subpopulations. At the same time, the group in which the number of "altruists" falls below the critical level, generally dies out completely, leaving no offspring, and the genes of the "egoists" and "deceivers" who made up this group are permanently withdrawn from the gene pool of the population. The more rigorous the selection takes place, the more chances the "altruists" have.
Not so long ago, a theory was put forward that altruism in humans developed under the influence of bloody intergroup conflicts. Alas, everything points to the fact that altruism within the group works best paired with parochialism – hostility to outsiders. Two opposite qualities ensure the effectiveness of each other, individually bringing little benefit.
Among other things, we conducted a number of experiments, one of which was a psychological test for children. It turned out that we don't know much about the formation of altruism and parochialism in childhood. The experiment consisted in the desire of children to share or not to share sweets. Some were given more sweets, others less, or allowed to distribute the sweets among themselves, each in turn.
During the experiment, it turned out that most of the children aged three or four years behave very selfishly, all the decisions made were focused only on obtaining their own benefits.
By the age of six, the situation is changing, and by eight, the willingness to help and share, as well as the desire for justice, is fully manifested. According to the test results, 5% of children at the age of eight are exceptionally kind–hearted, ready to share everything, and 15% are complete egoists. And, interestingly, the golden mean, which at all costs wanted justice, equal division among all, amounted to as much as 30%. The remaining 50% are all sorts of moderate, albeit with a creak, but they understand the need for some equalization. Another curious fact: as we grow older, the share of absolute good-natured people remains unchanged, the share of absolute egoists decreases, and the share of "fighters for justice" grows. Moderates also evolve with age towards egalitarianism (egalitarianism).
One can only guess why there is such an unequal distribution of good-natured and egoists. But the expediency of a large number of "fighters for justice" is quite obvious. This is a "morality police" laid down at the genetic level, and then developed by education, which will not allow countless egoists to breed and destroy cooperation between people.
The results of the study of child psychology also fit well into the framework of the theory of the development of altruism together with parochialism – to share with your own, to be greedy with others.
These traits are more pronounced in boys than in girls, since males were the main participants in intergroup conflicts.
Men in the ancient tribe were interested in the health of each warrior, as this gave a great chance of winning an intergroup conflict. The woman gained or lost relatively little from this: the maximum bad thing that could happen was a change of partner. For a man, the stake was the death or loss of a partner.
Wars in the Paleolithic were very bloody, they accounted for from 5 to 30% of all deaths. The willingness of an individual to die for his group increased the chances of victory, but reduced his personal chances of leaving offspring. This is where statistics come in.
The selflessness of the altruists and the altruists themselves should be enough to be enough for the dead "heroes" who ensured the victory and reproductive success of the surviving altruists. Therefore, primitive people were strongly interested in maintaining altruistic traits and suppressing egoism, not only at the level of genes, but also culture and upbringing. There is an opinion that the task of religion was to support parochial altruism. This phenomenon can be considered as a by-product of the development of a culture aimed at maintaining altruism in people. It turns out that intergroup aggression in primitive people was at a high enough level to spread the "altruism gene" among the entire species. The question remains open: is human culture able to find a way to "produce" a sufficient amount of altruism and not cultivate its "dark side" – hatred of outsiders? I would like to hope that she is capable, and history gives us certain, though not too great reasons for optimism.
In animals, in the vast majority of cases, altruism is focused on relatives (actually, this is the essence of kin selection). And only in very highly developed animals that can choose a partner, monitor the progress of affairs and punish deceivers, the concept of "own" does not necessarily coincide with the concept of "relative".
Actually, a reasonable person is the only species in which this kind of altruism is fully manifested. Only human society has risen to such a degree of whimsicality that self-sacrifice in favor of a genetic alien can eventually benefit the preservation of its own genotype. Together with the development of an effective elimination of danger and a strict intraspecific hierarchy, altruism made man the most successful biological species on Earth and allowed him to rise above the entire animal world.
With the development of a complex nervous system in humans, the need for cooperation for the general care of offspring has increased. The reason for this was the delayed maturation of the cubs, who needed at least 16 years to form the brain before puberty. This has become a strong social "glue". The care of the offspring lay not only on the shoulders of the parents, but also on the entire tribe for a long time. Caring for offspring and willingness to sacrifice themselves for the sake of the future generation. The absence of hereditary parental instincts excluded their transmission to the offspring, since it simply did not survive. And this "defect", from the point of view of selection, was no longer transmitted. Thus, a person preserved and improved the institution of the family.
A person could no longer eat carrion left by predators, but become a predator himself, the most ferocious among all. But he needed to cooperate to organize the hunt. A person could not cope with a large beast alone – our body is too weak for this. And meat provided the necessary amino acids (for the development of the same nervous system) and energy. Here everything is like in an intergroup competition, only the "piece" is divided by different types.
With the development of speech, there was a need to accumulate information and transfer experience. Since there were no other carriers of information, except for transmission from person to person, there was a need to take care of the elderly, which previously did not make much sense, since individuals who have lost the ability to reproduce are of no value to nature. Thus, the cult of ancestors and respect for the elderly appeared. Populations where the elderly were not cared for due to limited natural resources, which were barely enough for the young, lagged far behind in development. An example is the tribes of polar hunters who got rid of the old people. Until the beginning of the twentieth century, they had no written language at all and used primitive labor tools.
Over time, the bloody Paleolithic ended, people became a little smarter and realized that it was possible to negotiate instead of mindlessly killing each other. And the intergroup competition has moved to a new level. Now it required a lot of brain effort. The selection went the "smart" way.
Although hostility to "outsiders" was part of our evolutionary history and largely contributed to the formation of our morality and the ability to cooperate, this does not mean that we should continue to follow the ancient "traditions" of chauvinism (which generates intergroup struggle) and speciality (species discrimination) of our ancestors. Evolutionary ethics explains our innate tendencies, but in no way justifies them. In order to immortalize ourselves in our genes, it is not necessary to live like an ancient hunter. Another fruit of evolution, reason, should be used. And in conclusion, one more quote from Richard Dawkins:
"Man is the only living being that is predominantly influenced by culture acquired as a result of learning and transmission to subsequent generations. According to some, the role of culture is so great that genes, selfish or not, in fact have no meaning for understanding human nature. Others disagree with them. It all depends on your position in the debate about what determines human qualities – heredity or environment… If it really turns out that genes have nothing to do with determining the behavior of modern humans, if we really differ in this respect from all other animals, nevertheless, it remains at least interesting to investigate the rule from which we have become an exception so recently. And if the species Homo sapiens is not as exceptional as we would like to think, then it is all the more important to study this rule."
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