Natural selection. Revelations of the universe - Natural selection or natural culling of people What natural selection occurs in the modern world

A fairly popular discourse these days (here’s where this vomit word stuck) is about natural selection in modern man, does it exist at all and, if so, in what direction does it push us. Well, I too will speculate on this topic. For simplicity, I will assume that no serious catastrophes will happen in the near future, civilization will continue to flourish and cover more and more new regions, and the main ethical guidelines will not change radically. I will not take into account gene therapy, although it seems to have already become a real prospect. Because it’s not far from gene therapy to human genetic engineering, and there you can’t guess which genes will become the squeak of capricious fashion.

Intelligence. This is what everyone is always interested in first of all. Well, man is a torch of reason, rising from the darkness of a meaningless animal existence. Among the broad masses there is traditionally a myth that the further we progress, the more we progress intellectually and degrade physically and, accordingly, the person of the future will become a kind of scumbag with a giant head on thin crooked legs. There is a logic to this; this has been the general trend over the last million years. Without going into details. But in general, this does not mean at all that the same trends remain relevant now. How are things really going?

In primitive times, when groups of people numbering several dozen people wandered through forests and savannas, intelligence really mattered. It depended on the intelligence of each person in such a tribe whether this tribe could escape from predators, provide themselves with food, water, good shelter and all sorts of other goodies. And this directly determined survival. Thus, evolution moved towards increasing intelligence.

In later and advanced times the situation changed. People began to live in large, complexly organized communities, division of labor appeared, civilization reached the stage when predators ceased to pose a serious threat, and intraspecific competition became the main factor of selection. Reproductive success now depended primarily on social status. Wealthy people in traditional societies acquired a bunch of wives and concubines, and the number of their children sometimes exceeded a hundred. A similar situation continued in the future, even in the supposedly monogamous era, the rulers of the world managed to father children not only for their wives, but also for all the surrounding maids, ladies-in-waiting, slaves and serfs.

With the female gender, things are somewhat more complicated. For women, status was always rather negatively related to the number of children. But here it is important not to forget that reproductive success over many generations matters, and not just the next one. Any woman could always receive the greatest dividends by raising a successful son - even if there is only one child, but there are many grandchildren. Therefore, her best strategy was to invest in the quality of her offspring rather than their quantity.

Social changes had an immediate impact. The brain of modern man is smaller than the brain of both Neanderthal and Cro-Magnon man. Yes, gentlemen, we have become stupid. Difficult childbirth has always restrained the growth of the cranium, and as soon as the need for high intelligence decreased, the resultant of the vectors of natural selection reversed.

Nevertheless, some form of positive selection for high intelligence existed. Reproductively successful were not only degenerate aristocrats, but also active enterprising people who achieved everything on their own. There were also skilled lovers who secretly charmed ladies, including with beautiful speeches and wit. To what extent are status, material wealth, and the ability to seduce related to intelligence? This is an extremely controversial issue, and on any forum it consistently causes an avalanche of furious flames. But still, they are probably somehow connected - to one degree or another.

But in the most recent decades, a new turn has taken place in the structure of human society: effective contraception has appeared. The popular and wealthy still lead a more intense and varied sex life, but now this no longer results in a large number of offspring. Of course, we can give individual examples where money and status provide an evolutionary advantage. Let's say an extremely ugly but wealthy lady undergoes plastic surgery, artificial insemination, or simply buys a husband, while her poor sister unfortunately remains childless forever. A wealthy man undergoes complex and expensive infertility treatment, while a poor man simply cannot afford it. A divorced man who pays alimony remarries and has a couple more children in addition to the ones he already has, but the other one, equally bald and shabby, but also poor, is not attractive to the ladies.

But these are all isolated incidents and they have little effect on the general trend. In general, the wealthy and educated leave fewer offspring. Moreover, the quality of these offspring also suffers, because They usually give birth to their first child at a fairly late age. Meanwhile, the older the father, the more mutations his sperm carries. After all, spermatogonia actively divide throughout life, and with each division more and more errors accumulate. A 50-year-old father passes on three times more mutations to his children than a 20-year-old father. Here it is important to separate the cutlets from the flies. Most of these mutations do not lead to any terrible diseases. They may be neutral, some of them may even be useful. But on average, if you look at large samples, children of older fathers, all other things being equal, are slightly less healthy and smart than their peers.

In words, we value intelligence, but in fact the only factor in modern reality that works in favor of intelligence is caesarean sections. This operation removes the limitation on the size of the skull in newborns. But this in itself is not enough: in order for people to become smarter, it is not enough that nothing interferes with this process; we still need some forces that would move us in the right direction. Do the smartest survive now? No, thanks to social policy and scientific and technological progress, everyone survives! Maybe smart people get an advantage when reproducing? Again, no, thanks to monogamy, contraceptives, social policy and certain cultural norms, everyone reproduces, and the smart ones are the worst!

Health, strength, endurance. Natural selection, of course, exists in some form; it simply cannot but exist. First of all, not all women are able to conceive and carry a child for at least six months, when it can already be delivered in a ditch. And not all men are able to produce viable sperm. For those who are still capable of this, selection begins already at the gamete stage. Most of them simply die, especially if we talk about sperm, and only a select few reach the goal. True, only a small part of the genes in germ cells is active, and therefore many breakdowns remain invisible for the time being. So this is a very targeted selection. The next stage is the embryonic stage of development. Many embryos die before the potential mother even knows she is pregnant. And finally, children and adults also sometimes die, despite all the advances of medicine. And very ugly boys and girls may never find a partner.

But stabilizing selection in terms of physical qualities in humans is, of course, greatly weakened. Only serious defects are cut off, and over time we become more frail and sickly. However, this is nothing particularly new. Humans have been moving in this direction since their emergence as a species. True, now the process has accelerated. Actually, this does not threaten us with any incredible catastrophes. Yes, people will be unable to survive without civilization. We still can’t do that. That's it, the point of no return has been passed. It's too late to get scared...

Sociality. This is the only thing that has always been consistently subjected to strict selection. Moreover, with the development of society, the enlargement and complexity of human settlements, the selection pressure only intensified. Those who cannot communicate do not reproduce. And sometimes they don’t even survive. At least that was the case until very recently. Although right now, with the advent of the Internet, perhaps a turning point has arrived.

Behavior, character, emotions. In fact, everyone who wants it has the opportunity to leave offspring. And... this is also a selection factor. And very powerful. Previously, it was absolutely not necessary to want children in order to have them. It was enough to want to fuck. There is even an opinion that there is no so-called reproductive instinct at all. The desire to take care of offspring in animals arises (and in some males it never arises) only by the fact of the presence of this very offspring - the appetite comes during eating. But if the reproductive instinct did not exist before, now it has every chance of appearing. According to all the laws of Darwinian selection, childfree children will die out, leaving only those who truly love and want children. I hope they will at least be good parents. And the desire to have a child does not at all exclude the desire to push him somewhere when he finally appears.

How else can you eliminate your genes from the human gene pool? For example, do something like this from a young age and find yourself in the clutches of the punitive system - for a long time or even forever. Impulsivity, physical violence and uncontrollable outbursts of aggression are not held in high esteem today (epileptoids, you're out of luck) and will clearly not be in the character of the person of the future. This does not mean that aggression, cruelty, and competition will disappear. No, they will simply take the form of sophisticated and camouflaged moral violence.

What's the result? A civilization, so to speak, not of valiant, straightforward warriors, but of hypocritical, crooked intriguers. Stupid and frail people, but caring mothers and fathers. If anything, people will not become stupid to the level of a cow. Still, you need some basic level of intelligence to survive in the technogenic environment: not to get hit by vehicles, not to grab exposed wires. And potential partners will reject those who are clearly defective. People will simply become very stupid, with an average IQ of about 70, for example. And in this mode, civilization can exist stably for a long time. You don’t need a lot of intelligence to perform your highly specialized functions, especially since everything that is possible is automated. It may even develop. Out of the entire multi-billion-dollar population, there will somehow be a thousand or two random smart people. But you don’t need more. And then, of course, he will die. Just like all civilizations before us perished. And everything will start all over again. Our descendants will build a new colossus with feet of clay. Or maybe not our descendants...

Something like this. Or not. Gene therapy and engineering, sperm banks, eugenics programs, the return of polygamy, environmental disasters or nuclear war - you never know what can disrupt the smooth flow of things.

The main purpose of man is, with the help of our Imagination, to further expand the Universe, conducting into it the corresponding vibrations or energy that we have developed.

The purpose is both the same for each soul and different. The difference is in exactly how Imagination is realized in the world: someone draws, someone designs, someone builds, sings, cooks, teaches children, cares for animals, etc. The main goal of a person is to be needed by people! The meaning of life for each of us is to turn our entire life, every moment of it, into a unique act of creativity! After all, in each of us there is a piece of the Creator himself, therefore we are essentially co-creators, and not servants of God.

You need to fill your every day with Imagination - be it cleaning the house, washing dishes, peeling potatoes, traveling in public transport, talking with others, etc., through all this you can increase and expand the Divine essence. The main thing is to create everything with your soul and in any business you must go from creation, not from destruction!

Any human action must be spiritualized, that is, it must be based on spiritual and moral principles, and not evil! The greatest goal of life is to live every moment not automatically, half asleep, but with Imagination, with love for what you do!

In this way, we will begin to repay our debt to the world. After all, as much as we took from life, we must return the same amount in the form of physical or intellectual labor, otherwise our behavior will be subject to correction through various diseases, troubles and misfortunes.

Any event that happens to us is a sign! Therefore, we must always stop and try to comprehend what is happening to us, because there are no accidents in life.

The main test of our wrong behavior or action is the observed inhibition in the implementation of our goals and plans. At this time, Nature itself seems to give us a pause to understand that we are going in the wrong direction and doing the wrong thing!

You need to understand and realize the possible reasons for your failures. If this continues, then the natural principles of natural selection of biological species are activated, and, due to various circumstances, a person finds himself on the side of the road of life, ending it as a degenerate homeless person, a drunkard, a drug addict, a chronic loser and suicide!

A person goes through three stages of development in his life:

Animal stage;

The stage of a rational animal, when in its life it is guided by natural instincts;

And the stage of man himself, when he consciously continues his development.

A person who is not motivated to develop is subject to slow extinction! He becomes unable to fulfill his mission on Earth, and therefore leaves as unnecessary.

The change in value orientation after the collapse of the USSR led to the fact that money began to play a dominant role in people’s lives, rather than spiritual and moral principles, which represent the basis for the development of all human civilization on Earth. Today we do not have a single law defining the principles of spiritual and moral development of man and society. All laws are aimed only at satisfying the needs of the body and there is not a single law concerning the human soul. And this cannot develop in our youth the proper respect for their parents and older people. There is a good folk wisdom: “Whoever does not honor his parents and elders does not walk in goodness!” Since young people cannot imagine themselves in old age, they automatically program themselves for a short-term life, which is why they do not live to old age, but die young. There's a lot to think about here!

Today, the majority of our population lives only by instincts of self-preservation, stuck in its development at the stage of a “reasonable animal”, not reaching the actual human being. So what do we want from each other - what feelings, what justice, what love and what kind of human relationships? After all, under capitalism, “Man is a wolf to man!” We were taught this in Soviet school!

A person must have a long-term goal in life, divided into stages, in order to achieve which he must realize himself more fully and be in demand by people. Since the goal is energetically secured “from above,” a person is given certain strengths and opportunities for its subsequent implementation. For successful step-by-step implementation of a goal, a person determines what he lacks for this: what knowledge, abilities, skills, professionalism, etc., striving to acquire and master all this. The Universe will always help him in this, it is only necessary that the person’s thoughts be pure.

Currently, there is an unfavorable economic situation in the country, and in the world as a whole. People lose their minds, their jobs, they begin to behave inappropriately, the space is saturated with human aggression, manifested in various forms. There is a formation of resonance of social evil due to the social disorder of people. People who, due to various circumstances, are thrown to the margins of society today are ready material for protests.

To survive in such conditions, you must try to develop strong-willed qualities, the ability to flexibly adapt to a rapidly changing environment, and this cannot be learned while sitting at a computer. You need to gain life experience, as well as practice real, not virtual, communication with people, not shy away from any work, but consider all this as a kind of training for your endurance and gaining experience. You must approach any work with soul, develop your personal and business qualities, otherwise you will fall under the millstone of natural selection. We must learn to structure ourselves from the inside and accustom ourselves to order in everything! After all, “God helps those who strive for order!” - so says popular wisdom.

It’s high time we realized that no one but ourselves can solve our problems for us! If you don’t have your own brains, then you can’t add someone else’s! Such people simply do not have an inner core, and over time, if they do not work on themselves, they will fall under natural culling.

And it’s good if such people have their own corner and those who can support them in old age? Otherwise, there is only one road - to where souls rest.

No need to be lazy today! Just think about it now - what will you live on in old age? Pull yourself together and go ahead! Acquire new specialties, take care of your health, because no one needs you in our hospitals! Seek and you will find! And everyone will be rewarded according to his deeds - this seems to be written in the Gospel.

Compiled by B. Ratnikov

Natural selection in the breeding of domestic animals represents the survival of animals more adapted to existing conditions, the death of those unadapted, and the development of adaptive characteristics as a result.

In the life of wild animals, especially herbivores, their ability to avoid being caught by predators plays an important role. The development of this ability is determined by adaptive coloration (mimicry), running speed, jumping strength, size and strength of horns and many other features.

Having domesticated animals, man took upon himself to protect them from predators. As a result, those new colors of domestic animals appeared and developed, with which their wild ancestors would have become victims of predators within a few days after birth. Huge horns were not needed either. Excessive running speed and mobility have turned from advantages into vices, making it difficult to care for productive animals. And low mobility and phlegmatism, associated with the ability to fatten, began to be especially valued. Many of those characteristics that, during the life of animals in the wild, would have led to their death, and therefore were rejected by natural selection, thanks to the weakening of natural selection due to the protection of human domestic animals, were able not only to appear, but also to develop.

Artificial selection. By leaving animals with desirable traits to breed and destroying or simply not allowing animals undesirable for the economy to reproduce, man has found the most powerful way to control the evolution of domestic animals and cultivated plants. This method, in contrast to natural selection, was called artificial selection by Charles Darwin.

Through artificial selection by man, the smallest deviations in the body of animals accumulate, moving in the desired direction. Artificial selection has been going on for thousands of years, since the times of primitive man and primary domestication, and most of the most important, most useful differences for humans between domestic animals and their wild ancestors were created primarily by artificial selection.

Charles Darwin, studying artificial selection and its role in the creation and improvement of breeds of domestic animals and varieties of cultivated plants, identified two of its forms: unconscious selection and methodical selection.

Unconscious selection- the primary and most primitive form of selection. By using it, a person does not set himself the task of obtaining a certain quality in future generations of animals. He simply leaves from among the animals he has those from which he currently hopes to receive greater benefit from their exploitation. Unconscious selection is a short-sighted technique at the present time and not effective enough. In modern cultural breeding farms it has been abandoned. But unconscious selection, carried out approximately in one direction for hundreds and thousands of years, undoubtedly played a huge historical role in the process of domestication and the formation of their distinctive characteristics in domestic animals.

Unlike unconscious selection methodical selection- zootechnical work with a long-range view. Methodical selection is carried out to solve certain problems of improving herds and breeds in a certain pre-planned direction. Purposefulness of methodological selection- its main feature. A person, using methodical selection, evaluates not only the individual characteristics of animals, but also their breeding merits, that is, the ability to produce offspring of the desired type, superior in quality to the merits of mothers or without their disadvantages, and in some cases better than both parents.

Selection is a way of solving the problem of obtaining animals with predetermined characteristics through deeply thought-out mating, which allows achieving the desired result with a fairly high probability. When selecting, they take into account not only the qualities of the mated animals, their suitability for the purpose of breeding, but also their similarities and dissimilarities with each other, relationship, age, etc.

Relative variability. In order for an animal to exist, develop, and be able to satisfy certain human needs, its body must have a certain conjugacy, interdependence of parts, called correlation.

Correlations can be positive or negative. For example, the milk production of a cow depends on the size of the udder, the development of the digestive organs, lung capacity, etc. Therefore, selection of animals based on the size of their milk yield leads not only to an increase in milk production, but also to better development of the udder, digestive system, lungs and other systems and organs whose work associated with an increase in milk production. Charles Darwin called such cases of changes in some characteristics through selection for other, related characteristics relative variability. Examples of negative correlative variability include: thinning of the bones, skin and horns of dairy cows, since part of the nutrients necessary for the construction of these organs is spent on milk production; deterioration in dairy cows' fattening ability, which inhibits milk productivity.

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The doctrine of natural selection was created by Charles Darwin and A. Wallace, who considered it as the main creative force directing the evolutionary process and determining its specific forms.

Natural selection is the process by which predominantly individuals with hereditary characteristics useful for given conditions survive and leave offspring.

Assessing natural selection from the standpoint of genetics, we can conclude that it essentially selects positive mutations and genetic combinations that arise during sexual reproduction, improving survival in populations, and rejects all negative mutations and combinations that worsen the survival of organisms. The latter simply die. Natural selection can also act at the level of reproduction of organisms, when weakened individuals either do not produce full-fledged offspring or do not leave offspring at all (for example, males who lost mating fights with stronger rivals; plants in conditions of light or nutrition deficiency, etc.) .

In this case, not just some specific positive or negative qualities of organisms are selected or discarded, but entire genotypes that carry these characteristics (including many other characteristics that influence the further course and speed of evolutionary processes).

Forms of natural selection

Currently, there are three main forms of natural selection, which are given in school textbooks on general biology.

Stabilizing natural selection

This form of natural selection is characteristic of stable conditions of existence that do not change for a long time. Therefore, in populations there is an accumulation of adaptations and selection of genotypes (and the phenotypes they form) that are appropriate specifically for existing conditions. When populations reach a certain set of adaptations that are optimal and sufficient for survival in given conditions, stabilizing selection begins to act, cutting off extreme variants of variability and favoring the preservation of some average conservative characteristics. All mutations and sexual recombinations that lead to deviations from this norm are eliminated by stabilizing selection.

For example, the length of the limbs of hares should provide them with sufficiently fast and stable movement, allowing them to escape from a pursuing predator. If the limbs are too short, the hares will not be able to escape from predators and will become easy prey before they have time to give birth. This is how carriers of short-legged genes are removed from hare populations. If the limbs are too long, the hares' running will become unstable, they will topple over, and predators will easily be able to catch up with them. This will lead to the removal of carriers of long-legged genes from hare populations. Only individuals with an optimal length of limbs and their optimal ratio to the size of the body will be able to survive and give birth to offspring. This is a manifestation of stabilizing selection. Under its pressure, genotypes that differ from some average and reasonable norm under given conditions are eliminated. The formation of protective (camouflaging) coloration also occurs in many animal species.

The same applies to the shape and size of flowers, which should ensure sustainable pollination by insects. If the flowers have a too narrow corolla or short stamens and pistils, then insects will not be able to reach them with their paws and proboscis and the flowers will be unpollinated and will not produce seeds. Thus, the formation of optimal sizes and shapes of flowers and inflorescences occurs.

Over very long periods of stabilizing selection, some species of organisms may arise whose phenotypes remain virtually unchanged for many millions of years, although their genotypes, of course, have undergone changes during this time. Examples include the lobe-finned fish coelacanth, sharks, scorpions and some other organisms.

Driving selection

This form of selection is typical for changing environmental conditions, when directed selection occurs in the direction of a changing factor. This is how mutations accumulate and the phenotype changes, associated with this factor and leading to a deviation from the average norm. An example is industrial melaninogenesis, which manifested itself in birch moth butterflies and some other species of lepidoptera, when, under the influence of industrial soot, birch tree trunks darkened and white butterflies (the result of stabilizing selection) became noticeable against this background, which caused them to be quickly eaten by birds. The benefit went to dark mutants, which successfully reproduced in new conditions and became the dominant form in birch moth populations.

A shift in the average value of the trait towards the active factor can explain the appearance of heat-loving and cold-loving, moisture-loving and drought-resistant, salt-loving species and forms in different representatives of the living world.

As a consequence of the action of driving selection, there have been numerous cases of adaptation of fungi, bacteria and other pathogens of human, animal and plant diseases to drugs and various pesticides. This is how forms resistant to these substances emerged.

During driving selection, divergence (branching) of characters usually does not occur, and some characters and the genotypes that carry them are smoothly replaced by others, without forming transitional or deviating forms.

Disruptive or disruptive selection

With this form of selection, extreme variants of adaptations receive advantages, and intermediate traits that have developed under conditions of stabilizing selection become inappropriate in new conditions, and their carriers die out.

Under the influence of disruptive selection, two or more forms of variability are formed, often leading to polymorphism - the existence of two or more phenotypic forms. This can be facilitated by different living conditions within the range, leading to the emergence of several local populations within the species (the so-called ecotypes).

For example, constant mowing of plants led to the appearance of a large rattle of two populations in the plant, actively reproducing in June and August, since regular mowing caused the extermination of the average July population.

With prolonged action of disruptive selection, the formation of two or more species may occur, inhabiting the same territory, but being active at different times. For example, frequent droughts in mid-summer, unfavorable for fungi, led to the appearance of spring and autumn species and forms.

Struggle for existence

The struggle for existence is the main operating mechanism of natural selection.

Charles Darwin drew attention to the fact that in nature there are always two opposing development trends:

1. the desire for unlimited reproduction and dispersal and
2. overpopulation, large crowding, the influence of other populations and living conditions, which inevitably lead to the emergence of a struggle for existence and limiting the development of species and their populations.

That is, the species strives to occupy all possible habitats for its existence. But the reality is often harsh, resulting in species numbers and habitats being significantly limited. It is the struggle for existence against the background of high mutagenesis and combinative variability during sexual reproduction that leads to the redistribution of characteristics, and its direct consequence is natural selection.

There are three main forms of struggle for existence.

Interspecies fight

This form, as the name suggests, is carried out at the interspecific level. Its mechanisms are complex biotic relationships that arise between species:

Combinations of these connections can improve or worsen living conditions and the rate of reproduction of populations in nature.

Intraspecific struggle

This form of struggle for existence is associated with overpopulation of populations, when competition arises between individuals of the same species for a place to live - for nesting, for light (in plants), moisture, nutrients, territory for hunting or grazing (in animals), etc. It manifests itself, for example, in skirmishes and fights in animals and in shading of rivals due to faster growth in plants.

This same form of struggle for existence also includes the struggle for females (mating tournaments) in many animals, when only the strongest male can leave offspring, and weak and inferior males are excluded from reproduction and their genes are not passed on to offspring.

Part of this form of struggle is caring for the offspring, which exists in many animals and helps reduce mortality among the younger generation.

Combating abiotic environmental factors

This form of struggle is most acute in years with extreme weather conditions - severe droughts, floods, frosts, fires, hail, eruptions, etc. Under these conditions, only the strongest and hardiest individuals can survive and leave offspring.

The role of selection of organisms in the evolution of the organic world

The most important factor in evolution (along with heredity, variability and other factors) is selection.

Evolution can be divided into natural and artificial. Natural evolution is called evolution that occurs in nature under the influence of natural environmental factors, excluding the direct direct influence of humans.

Artificial evolution is called evolution carried out by man in order to develop forms of organisms that satisfy his needs.

Selection plays an important role in both natural and artificial evolution.

Selection is either the survival of organisms more adapted to a given environment, or the culling of forms that do not meet certain criteria.

In this regard, two forms of selection are distinguished - artificial and natural.

The creative role of artificial selection is that a person creatively approaches the breeding of a plant variety, an animal breed, a strain of microorganisms, combining different methods of selection and selection of organisms in order to form characteristics that best suit human needs.

Natural selection is the survival of individuals most adapted to specific conditions of existence, and their ability to leave offspring that are fully functional under given conditions of existence.

As a result of genetic research, it became possible to distinguish two types of natural selection - stabilizing and driving.

Stabilizing is a type of natural selection in which only those individuals survive whose characteristics strictly correspond to given specific environmental conditions, and organisms with new characteristics resulting from mutations die or do not produce full-fledged offspring.

For example, a plant is adapted to pollination by a given specific type of insect (it has strictly defined sizes of flower elements and their structure). A change occurred - the cup size increased. The insect freely penetrates inside the flower without touching the stamens, due to which pollen does not fall on the body of the insect, which prevents the possibility of pollinating the next flower. This will lead to the fact that the plant will not produce offspring and the resulting trait will not be inherited. If the calyx size is very small, pollination is generally impossible, since the insect will not be able to penetrate the flower.

Stabilizing selection makes it possible to lengthen the historical period of existence of a species, since it does not allow the characteristics of the species to be “eroded.”

Driving selection is the survival of those organisms that develop new characteristics that allow them to survive in new environmental conditions.

An example of driving selection is the survival of dark-colored butterflies against a background of smoked birch trunks in a population of light-colored butterflies.

The role of driving selection is the possibility of the emergence of new species, which, along with other factors of evolution, made possible the emergence of the modern diversity of the organic world.

The creative role of natural selection is that through various forms of struggle for existence, organisms develop characteristics that allow them to most fully adapt to given environmental conditions. These useful traits are fixed in organisms due to the survival of individuals that have such traits and the extinction of those individuals that do not have useful traits.

For example, reindeer are adapted to life in the polar tundra. He can survive there and give birth to normal fertile offspring if he can get his food normally. The deer's food is moss (reindeer moss, a lichen). It is known that the tundra has a long winter and food is hidden under the snow cover, which the deer needs to destroy. This will become possible only if the deer has very strong legs equipped with wide hooves. If only one of these signs is realized, then the deer will not survive. Thus, in the process of evolution, only those individuals survive that possess the two characteristics described above (this is the essence of the creative role of natural selection in relation to reindeer).

It is important to understand the differences between natural and artificial selection. They are:

1. artificial selection is carried out by humans, and natural selection is spontaneously realized in nature under the influence of external environmental factors;
2. the result of artificial selection is new breeds of animals, plant varieties and strains of microorganisms with traits useful for human economic activity, and with natural selection new (any) organisms arise with traits that allow them to survive in strictly defined environmental conditions;
3. during artificial selection, the traits that arise in organisms may not only not be useful, they may be harmful for a given organism (but they are useful for human activity); with natural selection, the resulting traits are useful for a given organism in a given, specific environment of its existence, since they contribute to its better survival in this environment;
4. natural selection has been carried out since the appearance of organisms on Earth, and artificial selection has been carried out only since the domestication of animals and the advent of agriculture (growing plants in special conditions).

So, selection is the most important driving force of evolution and is realized through the struggle for existence (the latter refers to natural selection).

Man was subject to natural selection at least until the mid-19th century.

A page from the parish book and a photo of a Finnish family (photo by the authors of the study).

Scientists have long debated whether natural selection acts on humans. In order for evolution to continue, it is necessary, firstly, to experience environmental pressure, and secondly, to produce enough offspring - so that evolution has plenty to choose from. Man learned to cultivate the land, thereby protecting himself from climatic vicissitudes and, in general, the vagaries of the environment, and moved primarily to monogamous marriage. Monogamy, as is easy to understand, greatly reduces the number of offspring.

So, after thousands and thousands of years of monogamous marriages and developing agriculture, has man remained under the rule of natural selection?

Researchers from the University of Sheffield (UK) answer this question in the affirmative. Scientists decided to trace population dynamics in four Finnish villages inhabited by farmers and fishermen from 1760 to 1849. The material was records in parish books, which reported who was born when, when they got married and how many children there were in the family. Obviously, we are talking exclusively about monogamous marriages, so it was easy to trace the ancestry of any child. Researchers were primarily interested in the variation in the number of children in native families, since it was precisely the different number of children that could provide material for evolution. A stable one or two children from family to family would remain beyond the reach of natural selection.

Scientists assessed several indicators: the age of puberty, how many survived to reach it, whether the person had his own family, how often he or she got married, and how many children there were from each marriage. The role of each of these factors in natural selection was determined separately. And, of course, it is not surprising that the main factor turned out to be the total number of children. Scientists named the second most important child and infant mortality rate, which was quite high among the Finns. The number of marriages mattered for “male” evolution, but not for “female” evolution. A man who remarried usually chose a new wife so that she could bear him more children, while women decided to remarry when they were already beyond reproductive age. That is, a man left more children than a woman, and therefore his genes experienced greater pressure from natural selection.

The scientists presented the results of their research in the journal PNAS.

It should be emphasized that they did not at all evaluate changes in the fitness of the population itself, nor did they analyze how resistant the inhabitants of these Finnish villages became, for example, in relation to some infections. Scientists simply assessed the possibility of such changes and whether such stability could, in principle, develop. Although it is now common to say that evolution is “pressing” modern humans with the help of bacteria and viruses, there is still almost no research that would analyze whether this is even possible. That is, whether the human population can respond to the pressures of natural selection. It turns out that it can. Therefore, it is possible that in the future there will be a person resistant to both hepatitis and HIV.

True, here one cannot help but admit that the study is partly artificial in relation to the present day. The old traditions by which peasant communities lived are now rapidly losing force, at least in developed countries. Perhaps somewhere in African villages or the Middle East, evolution is still cherry-picking the human population for the fittest, but is natural selection at work around the Garden Ring in Moscow or Manhattan?