Features of human ancestors at different stages of evolution. Main stages of human evolution

Moreover, we are now doing it much faster than before. Over the past 10,000 years, the rate of evolution has increased 100-fold, causing our genes to mutate and selecting from those mutations the most beneficial ones. We are not the top of the evolutionary chain. At best - the middle!

We drink milk

The gene that regulates human absorption of lactose has developed in us during evolution. Initially, a person could only absorb mother's milk in infancy. However, as a result of the domestication of cows, goats, sheep and the development of cattle breeding, our body began to produce a hormone that promotes the breakdown of lactose. People with this gene had an advantage in spreading their own genes.

A 2006 study confirmed that this gene is still evolving as it was 3,000 years ago in East Africa. A genetic mutation that promotes the absorption of lactose is now present in 95% of Europeans.

Many people never grow wisdom teeth.

The diet of ancient man largely consisted of roots, leaves and nuts. This diet caused teeth to wear out quite quickly. Wisdom teeth are an evolutionary answer to this problem. A kind of reserve, stored for the time being right in the mouth of our ancestors and appearing precisely when the other teeth had already served their purpose. It was they who did not allow the ancient man to die in the prime of his life from hunger due to such a misunderstanding as caries or an overly hard nut.

Today's food is much softer, and we have all kinds of devices for grinding it. Wisdom teeth are no longer needed because the rest serve us much longer. That's why we have to part with the extra pair.

Our immunity has increased

In 2007, a group of scientists from Royal Holloway College, University of London, conducted a study aimed at identifying the latest signs of evolution. To do this, they studied about 1,800 genes that appeared in humans over the last 40,000 years. The vast majority of these genes are in one way or another associated with a person’s ability to resist infectious diseases. Scientists have come to interesting conclusions.

About 12 new genes have been distributed among Africans that help the body effectively fight malaria. Residents of large cities are armed with genes that allow them to fight tuberculosis and leprosy. Thus, the place of residence (or “habitat,” as scientists would say) influences the formation of immunity.

Our brains are shrinking in size

While you feel a sense of superiority over the animal world due to the size of your brain, which makes you the crown of creation, your brain becomes smaller. Over the past 30,000 years, the average volume of the human brain has decreased from 1500 cubic centimeters to 1350! The difference is about the size of a tennis ball.

Scientists have several theories about the reasons for this. First: we are becoming dumber, the reason for this is the high standard of living and the complex organization of society. Simply put, now you don’t have to be a very smart guy to survive. Another theory suggests that a small brain is much more efficient than a large one because neural connections are made much faster. Finally, there is a theory that smaller brains make our species more social, allowing us to function more effectively in groups. Or its ersatz - Facebook.

Some of us have blue eyes

In theory, we should all have brown eyes. But 100,000 years ago, somewhere in the vicinity of the Black Sea, a mutation appeared that gives the eyes a blue color. Why it was preserved remains a mystery. After all, as you probably remember from your school biology course, the gene for brown eyes is dominant, and the gene for blue eyes is recessive, which means that it needs to try very hard to come to power. Nevertheless, blue eyes are not uncommon these days; the gene is determined to survive in the most decisive manner. Moreover, he programs his masters.

A 2007 study found that blue-eyed men and women find members of the opposite sex with blue eyes more attractive. But brown-eyed people do not show the same integrity.

Anthropogenesis (Greek anthropos man, génesis origin), part biological evolution, which led to the emergence of the species Homo sapiens, which separated from other hominids, anthropoid

monkeys and monkeys placental mammals. This is the process of historical and evolutionary formation of the physical type of a person, the initial development of his labor activity, speech, and society.

Stages of human evolution

Scientists claim that modern man did not descend from modern apes, which are characterized by narrow specialization (adaptation to a strictly defined way of life in tropical forests), but from highly organized animals that died out several million years ago - dryopithecus.

According to paleontological finds (fossil remains), about 30 million years ago ancient primates Parapithecus appeared on Earth, living in open spaces and in trees. Their jaws and teeth were similar to those of apes. Parapithecus gave rise to modern gibbons and orangutans, as well as the extinct branch of Dryopithecus. The latter in their development were divided into three lines: one of them led to the modern gorilla, the other to the chimpanzee, and the third to Australopithecus, and from him to man. The relationship of Dryopithecus with humans was established based on a study of the structure of its jaw and teeth, discovered in 1856 in France. The most important stage on the path to the transformation of ape-like animals into ancient people was the appearance of upright walking. Due to climate change and forest thinning, a transition has occurred from an arboreal to a terrestrial way of life; in order to better survey the area where human ancestors had many enemies, they had to stand on their hind limbs. Subsequently, natural selection developed and consolidated upright posture, and, as a consequence of this, the hands were freed from the functions of support and movement. This is how Australopithecines arose - the genus to which hominids (a family of humans) belong..

Australopithecus

Australopithecines are highly developed bipedal primates that used objects of natural origin as tools (hence, Australopithecines cannot yet be considered human). Bone remains of Australopithecines were first discovered in 1924 in South Africa. They were as tall as a chimpanzee and weighed about 50 kg, their brain volume reached 500 cm3 - according to this feature, Australopithecus is closer to humans than any of the fossil and modern monkeys.

The structure of the pelvic bones and the position of the head were similar to those of humans, indicating an upright position of the body. They lived about 9 million years ago in the open steppes and ate plant and animal foods. The tools of their labor were stones, bones, sticks, jaws without traces of artificial processing.

A skilled man

Not having a narrow specialization of the general structure, Australopithecus gave rise to a more progressive form, called Homo habilis - a skilled person. Its bone remains were discovered in 1959 in Tanzania. Their age is determined to be approximately 2 million years. The height of this creature reached 150 cm. The volume of the brain was 100 cm3 larger than that of australopithecines, the teeth of the human type, the phalanges of the fingers were flattened like those of a person.

Although it combined the characteristics of both monkeys and humans, the transition of this creature to the manufacture of pebble tools (well-made stone) indicates the appearance of its labor activity. They could catch animals, throw stones and perform other actions. The piles of bones found with the Homo habilis fossils indicate that meat became a regular part of their diet. These hominids used crude stone tools.

Homo erectus

Homo erectus is a man who walks upright. the species from which modern humans are believed to have evolved. Its age is 1.5 million years. Its jaws, teeth and brow ridges were still massive, but the brain volume of some individuals was the same as that of modern humans.

Some Homo erectus bones have been found in caves, suggesting its permanent home. In addition to animal bones and fairly well-made stone tools, heaps of charcoal and burnt bones were found in some caves, so, apparently, at this time, Australopithecines had already learned to make fire.

This stage of hominid evolution coincides with the settlement of other colder regions by people from Africa. It would be impossible to survive cold winters without developing complex behaviors or technical skills. Scientists hypothesize that the prehuman brain of Homo erectus was capable of finding social and technical solutions (fire, clothing, food storage, and cave dwelling) to the problems associated with surviving the winter cold.

Thus, all fossil hominids, especially australopithecus, are considered to be the predecessors of humans.

The evolution of the physical characteristics of the first people, including modern man, covers three stages: ancient people, or archanthropes;ancient people, or paleoanthropes;modern people, or neoanthropes.

Archanthropes

The first representative of the archanthropes is Pithecanthropus (Japanese man) - an ape-man who walks upright. His bones were found on the island. Java (Indonesia) in 1891. Initially, its age was determined to be 1 million years, but, according to a more accurate modern estimate, it is slightly more than 400 thousand years old. The height of Pithecanthropus was about 170 cm, the volume of the skull was 900 cm3. Somewhat later, there was Sinanthropus (Chinese man). Numerous remains of it were found in the period 1927 to 1963. in a cave near Beijing. This creature used fire and made stone tools. This group of ancient people also includes Heidelberg Man.

Paleoanthropes

Paleoanthropes - Neanderthals appeared to replace the Archanthropes. 250-100 thousand years ago they were widely distributed throughout Europe. Africa. Western and South Asia. Neanderthals made a variety of stone tools: hand axes, scrapers, pointed points; they used fire and rough clothing. Their brain volume increased to 1400 cm3.

The structural features of the lower jaw show that they had rudimentary speech. They lived in groups of 50-100 individuals and during the advance of glaciers they used caves, driving wild animals out of them.

Neoanthropes and Homo sapiens

Neanderthals were replaced by modern people - Cro-Magnons - or neoanthropes. They appeared about 50 thousand years ago (their bone remains were found in 1868 in France). Cro-Magnons form the only genus of the species Homo Sapiens - Homo sapiens. Their ape-like features were completely smoothed out, there was a characteristic chin protuberance on the lower jaw, indicating their ability to articulate speech, and in the art of making various tools from stone, bone and horn, the Cro-Magnons went far ahead compared to the Neanderthals.

They tamed animals and began to master agriculture, which allowed them to get rid of hunger and obtain a variety of food. Unlike their predecessors, the evolution of Cro-Magnons took place under the great influence of social factors (team unity, mutual support, improvement of work activity, a higher level of thinking).

The emergence of Cro-Magnons is the final stage in the formation of modern man . The primitive human herd was replaced by the first tribal system, which completed the formation of human society, the further progress of which began to be determined by socio-economic laws.

18) Evidence of the origin of man from animals. Atavisms and rudiments in humans.

TO it is traditionally referred to comparative anatomical, embryological, physiological and biochemical, molecular genetic, paleontological.

1. Comparative anatomical.

The general plan of the human body structure is similar to the body structure of chordates. The skeleton consists of the same sections as those of other mammals. The body cavity is divided by the diaphragm into abdominal and thoracic sections. The nervous system is tubular type. In the middle ear there are three auditory ossicles (hammer, incus, stirrup), there are auricles and associated auricular muscles. Human skin, like other mammals, contains mammary, sebaceous and sweat glands. The circulatory system is closed, there is a four-chambered heart. Confirmation of the animal origin of man is the presence of rudiments and atavisms.

2. Embryological.

In human embryogenesis, the main stages of development characteristic of vertebrates are observed (cleavage, blastula, gastrula, etc.). In the early stages of embryonic development, the human embryo develops signs characteristic of lower vertebrates: notochord, gill slits in the pharyngeal cavity, hollow nerve tube, bilateral symmetry in the structure of the body, smooth surface of the brain. The further development of the embryo exhibits features characteristic of mammals: several pairs of nipples, the presence of hair on the surface of the body, as in all mammals (except monotremes and marsupials), the development of the baby inside the mother’s body and nutrition of the fetus through the placenta.

3. Physiological and biochemical.

In humans and apes, the structure of hemoglobin and other body proteins is very similar. There are similarities in blood groups. The blood of the pygmy chimpanzee (bonobo) of the corresponding group can be transfused to humans. Humans also have the Rh blood antigen (it was first identified in the Rhesus monkey). Apes are close to humans in terms of the duration of pregnancy and the timing of puberty.

4. Molecular genetic.

All apes have a diploid number of chromosomes 2 n = 48. In humans, 2 n = 46 (it has been established that chromosome 2 in humans is formed by the fusion of two chromosomes, homologous to those in chimpanzees). There is a high degree of homology in the primary structure of genes (more than 90% of human and chimpanzee genes are similar to each other).

5. Paleontological.

Numerous fossil remains have been found (individual bones, teeth, skeletal fragments, tools, etc.), which make it possible to compile an evolutionary series of ancestral forms of modern humans and explain the main directions of their evolution.

Difference between humans and animals

Hereditary changes that arose during evolution under the control of natural selection contributed to the appearance of upright posture in humans, the freeing of hands, the development and enlargement of the brain skull, and the reduction of its facial part. At the same time, humans developed a need for the systematic production of tools, which contributed to the improvement of the structure and function of the hand, brain, speech apparatus, mental activity and the emergence of speech. Binocular (stereoscopic) color vision, which was present in human ancestors, played a significant role in the development of the brain and hand.

Atavisms and rudiments in humans.

Rudiments are organs that have lost their basic significance in the process of evolutionary development of the organism.

Many vestigial organs are not completely useless and perform some minor functions with the help of structures apparently intended for more complex purposes.

Atavism is the appearance in an individual of characteristics characteristic of distant ancestors, but absent in nearby ones.

The appearance of atavisms is explained by the fact that the genes responsible for this trait are preserved in the DNA, but do not function because they are suppressed by the action of other genes.

Rudiments in humans:

∙ caudal vertebrae;

∙ some humans have a vestigial tail muscle, extensor coccygis, identical to the muscles that move the tail in other mammals. It is attached to the tailbone, but since the tailbone in humans can hardly move, this muscle is useless to humans;

∙ body hair;

∙ special muscles arrectores pilorum, which in our ancestors served to “raise the fur on end” (this is useful for thermoregulation, and also helps animals look larger - to intimidate predators and competitors). In humans, contraction of these muscles results in “goose bumps,” which is unlikely to have some adaptive value;

∙ three ear muscles that allowed our ancestors to move their ears. There are people who know how to use these muscles. This helps animals with large ears determine the direction of the sound source, but in humans this ability can only be used for fun;

∙ Morgani ventricles of the larynx;

∙ vermiform appendix of the cecum (appendix). Long-term observations have shown that removal of the appendix does not have a significant effect on people’s life expectancy and health, except for the fact that after this operation people, on average, suffer from colitis slightly less often;

∙ grasping reflex in newborns (it helps baby monkeys hold on to their mother’s fur);

∙ hiccups: we inherited this reflex movement from our distant ancestors - amphibians. In a tadpole, this reflex allows a portion of water to quickly pass through the gill slits. In both humans and tadpoles, this reflex is controlled by the same part of the brain and can be suppressed by the same means (for example, inhaling carbon dioxide or straightening the chest);

∙ lanugo: hair growth that develops in a human embryo on almost the entire body except the palms and soles of the feet, and disappears shortly before birth (premature babies are sometimes born with lanugo).

Examples of atavisms:

∙ caudal appendage in humans;

∙ continuous hair on the human body;

∙ additional pairs of mammary glands;

19 . Aging of the body. Theories of aging. Geriatrics and gerontology.

Old age is a stage of individual development, upon reaching which the body experiences natural changes in its physical condition, appearance, and emotional sphere. Senile changes become obvious and increase in the post-reproductive period of ontogenesis. However, the beginning of the decline of reproductive function or even its complete loss cannot serve as the lower limit of old age. Indeed, menopause in women, which consists in the cessation of the release of mature eggs from the ovary and, accordingly, the cessation of monthly bleeding, determines the end of the reproductive period of life. However, by the time menopause is reached, most functions and external signs are far from reaching the state characteristic of old people. On the other hand, many of the changes we associate with old age begin before the decline in reproductive function. This applies both to physical signs (greying of hair, development of farsightedness) and to the functions of various organs. For example, in men, a decrease in the release of male sex hormones by the gonads and an increase in the release of gonadotropic hormones by the pituitary gland, which is typical for an old organism, begins at about 25 years of age.

There are chronological and biological (physiological) ages.

According to the modern classification, based on the assessment of many average indicators of the state of the body, people whose chronological age has reached 60-74 years are called elderly, 75-89 years old - old, over 90 years old - centenarians. Accurate determination of biological age is complicated by the fact that individual signs of old age appear at different chronological ages and are characterized by different rates of increase. In addition, age-related changes in even one trait are subject to significant gender and individual variations.

Let's consider such a sign as the firmness (elasticity) of the skin. In this case, the same biological age is reached by a woman at about 30 years old, and by a man at 80. That is why, first of all, women need competent and constant skin care. In order to determine biological age, which is necessary for judging the rate of aging, batteries of tests are used, conducting a combined assessment of many signs that naturally change during life.

The basis of such batteries are complex functional indicators, the state of which depends on the coordinated activity of several body systems. Simple tests are usually less informative. For example, the speed of propagation of a nerve impulse, which depends on the state of the nerve fiber, decreases in the age range of 20-90 years by 10%, while the vital capacity of the lungs, determined by the coordinated work of the respiratory, nervous and muscular systems, decreases by 50%.

The state of old age is achieved through changes that make up the content of the aging process. This process covers all levels of the structural organization of an individual - molecular, subcellular, cellular, tissue, organ. The overall result of numerous partial manifestations of aging at the level of the whole organism is an increasing decrease in the viability of the individual with age, a decrease in the effectiveness of adaptive, homeostatic mechanisms. It has been shown, for example, that young rats, after immersion in ice water for 3 minutes, restore their body temperature in about 1 hour. Middle-aged animals require 1.5 hours, and old ones - about 2 hours.

In general, aging leads to a progressive increase in the likelihood of death. Thus, the biological meaning of aging is that it makes the death of the organism inevitable. The latter is a universal way to limit the participation of a multicellular organism in reproduction. Without death, there would be no change of generations - one of the main conditions of the evolutionary process.

Age-related changes in the aging process do not in all cases involve a decrease in the body's adaptability. In the course of life, humans and higher vertebrates gain experience and develop the ability to avoid potentially dangerous situations. The immune system is also interesting in this regard. Although its effectiveness generally decreases after the organism reaches a state of maturity, thanks to “immunological memory” in relation to some infections, old individuals may be more protected than young ones.

HYPOTHESES EXPLAINING THE MECHANISMS OF AGING

Gerontology knows at least 500 hypotheses that explain both the root cause and the mechanisms of aging of the body. The vast majority of them have not stood the test of time and are of purely historical interest. These, in particular, include hypotheses linking aging with the consumption of a special substance of cell nuclei, the fear of death, the loss of some non-renewable substances received by the body at the time of fertilization, self-poisoning with waste products, and the toxicity of products formed under the influence of the microflora of the large intestine. Hypotheses that are of scientific value today correspond to one of two main directions.

Some authors consider aging as a stochastic process of age-related accumulation of “errors” that inevitably occur during normal life processes, as well as damage to biological mechanisms under the influence of internal (spontaneous mutations) or external (ionizing radiation) factors. Stochasticity is determined by the random nature of changes in time and location in the body. In various versions of hypotheses in this direction, the primary role is assigned to various intracellular structures, the primary damage of which determines functional disorders at the cellular, tissue and organ levels. First of all, this is the genetic apparatus of cells (hypothesis of somatic mutations). Many researchers associate the initial changes in the aging of the body with changes in the structure and, consequently, the physicochemical and biological properties of macromolecules: DNA, RNA, chromatin proteins, cytoplasmic and nuclear proteins, enzymes. Cell membrane lipids, which are often targets for free radicals, also stand out. Failures in the functioning of receptors, in particular cell membranes, disrupt the effectiveness of regulatory mechanisms, which leads to a mismatch in vital processes.

The direction under consideration also includes hypotheses that see the fundamental basis of aging in the increasing wear and tear of structures with age, ranging from macromolecules to the organism as a whole, ultimately leading to a state incompatible with life. This view, however, is too straightforward.

Let us recall that the emergence and accumulation of mutational changes in DNA are resisted by natural antimutational mechanisms, and the harmful consequences of the formation of free radicals

are reduced due to the functioning of antioxidant mechanisms. Thus, if the “concept of wear and tear” of biological structures correctly reflects the essence of aging, then the result in the form of a greater or lesser rate of senile changes, the age at which these changes become obvious in different people, is a consequence of the superposition of destructive and protective processes. In this case, the wear hypothesis inevitably includes

factors such as genetic predisposition, conditions and even lifestyle, on which, as we have seen, the rate of aging depends.

The second direction is represented by genetic or program hypotheses, according to which the aging process is under direct genetic control. This control, according to one view, is carried out using special genes. According to other views, it is associated with the presence of special genetic programs, as is the case with other stages of ontogenesis, for example embryonic.

There is evidence in favor of the programmed nature of aging, many of which have already been discussed in Section. 8.6.1. Usually they also refer to the presence in nature of species in which, following reproduction, changes rapidly increase, leading to the death of animals. A typical example is Pacific salmon (sockeye salmon, pink salmon), which die after spawning. The triggering mechanism in this case is associated with a change in the secretion regime of sex hormones, which should be considered as a feature of the genetic program of individual development of salmonids, reflecting their ecology, and not as a universal mechanism of aging.

It is noteworthy that castrated pink salmon do not spawn and live 2-3 times longer. It is during these additional years of life that we should expect signs of aging to appear in cells and tissues. Some program hypotheses are based on the assumption that a biological clock functions in the body, in accordance with which age-related changes occur. The role of the “clock” is attributed, in particular, to the thymus gland, which ceases functioning when the body enters adulthood. Another candidate is the nervous system, especially some of its parts (hypothalamus, sympathetic nervous system), the main functional element of which is primarily aging nerve cells. Let us assume that the cessation of thymus functions at a certain age, which is undoubtedly under genetic control, is a signal of the beginning of aging of the body. This, however, does not mean genetic control of the aging process. In the absence of the thymus, immunological control over autoimmune processes is weakened. But in order for these processes to take place, either mutant lymphocytes (DNA damage) or proteins with altered structure and antigenic properties are required.

Gerontology and Geriatrics

Gerontology (from the Greek gerontos - old man) is a branch of biology and medicine that studies the patterns of aging of living beings, including humans. The main areas of gerontology include the study of the main causes, mechanisms and conditions of aging, the search for effective means of increasing life expectancy and extending the period of active working capacity.

Geriatrics (from the Greek iatreia - treatment) is a field of clinical medicine that studies the diagnosis, treatment and prevention of diseases of elderly and senile people.

There are many theories that suggest different ways for the human body to develop in the future. Scientists are constantly looking for clues about where we came from and where we are going. Some experts argue that Darwinian natural selection continues, while others believe that humans have already reached their peak.

For example, Professor Steve Jones from University College London says that the driving forces of evolution no longer play an important role in our lives. Among the people who lived a million years ago, it was literally survival of the fittest, and the hostile environment had a direct impact on the human form. In the modern world with central heating and plenty of food, mutations are much less likely.

However, there is a possibility that our bodies will continue to develop further. Humans can continue to adapt to the changes taking place on our planet, which is becoming increasingly polluted and dependent on technology. According to the theory, animals evolve faster in isolated environments, while people living in the 21st century are not isolated at all. However, this issue is also controversial. With new advances in science and technology, people were able to exchange information instantly, but at the same time they became more isolated than ever before.

Yale University professor Stephen Stearns says that globalization, immigration, cultural diffusion and ease of travel are all contributing to the gradual homogenization of the population, which will lead to a homogenization of facial features. Recessive traits in humans, such as freckles or blue eyes, will become very rare.

In 2002, a study by epidemiologists Mark Grant and Diane Lauderdale found that only 1 in 6 non-Hispanic white Americans had blue eyes, whereas 100 years ago, more than half of the white population in the United States had blue eyes. It is predicted that the skin and hair color of the average American will darken, leaving very few blondes and people with very dark or very light skin.

In some parts of the planet (for example, in the USA), genetic mixing occurs more actively, in others - less. In some places, unique physical traits adapted to the environment have a strong evolutionary advantage, so people won't be able to give them up so easily. Immigration in some regions is much slower, so, according to Stearns, complete homogenization of the human race may never happen.

However, overall the Earth is becoming more and more like a big melting pot, and a scientist has said that in a few centuries we will all become like the Brazilians. It is possible that in the future people may acquire the ability to consciously change the color of their skin thanks to the artificial introduction of chromatophores (pigment-containing cells present in amphibians, fish, and reptiles) into the body. There may be another method, but in any case it will provide some advantages. Firstly, interracial prejudices will finally disappear. Secondly, being able to change will help you stand out in modern society.

Height

The trend toward increased growth has been reliably established. Primitive people are thought to have had an average height of 160 cm, and human height has been steadily increasing over the past centuries. A particularly noticeable jump has occurred in recent decades, when human height has increased by an average of 10 cm. This trend may continue in the future, since it largely depends on diet, and food is becoming more nutritious and affordable. Of course, at the moment in some regions of the planet, due to poor nutrition with a low content of minerals, vitamins and proteins, this trend is not observed, but in most countries of the world people continue to grow. For example, every fifth resident of Italy is taller than 180 centimeters, while after the Second World War there were only 6% of such people in the country.

beauty

Researchers have previously found that more attractive women have more children than less attractive women, and that more children are girls. Their daughters grow into attractive, mature women, and the pattern repeats itself. Scientists from the University of Helsinki concluded that the trend towards an increase in the number of beautiful women is increasing with each new generation. However, the trend does not apply to men. However, the person of the future will likely be more beautiful than he is now. His body structure and facial features will reflect what most are looking for in a partner today. He will have finer facial features, an athletic build and a good figure. Another idea, proposed by evolutionary theorist Oliver Curry of the London School of Economics, seems to be inspired by ideas from classic science fiction. According to his hypothesis, the human race will over time be divided into two subspecies: a lower class, consisting of short people who look like underdeveloped goblins, and a higher class of tall, slender, attractive and intelligent superhumans, spoiled by technology. According to Curry's forecasts, this will not happen soon - in 100 thousand years.

Big heads

If a person continues to develop, turning into a more complex and intelligent being, his brain will become larger and larger.

With technological progress, we will depend more and more on the intellect and brain and less and less on our other organs. However, paleontologist Peter Ward from the University of Washington in Seattle disagrees with this theory. “If you've ever experienced or witnessed childbirth, then you know that with our anatomical structure we stand at the very edge - our big brains are already causing extreme problems during childbirth, and if they got bigger and bigger, then this would cause greater maternal mortality during childbirth, and evolution will not follow this path.”

Obesity

A recent study by Columbia University and Oxford University researchers predicts that by 2030, half the US population will be obese. That is, there will be 65 million more adults with problematic weight in the country. If you think that Europeans will be slim and elegant, then you are mistaken. Obesity rates have more than doubled in most European Union member states over the past two decades, according to a report published by the Paris-based Organization for Economic Co-operation and Development. As a result, on average, more than 15% of European adults and one in seven children suffer from obesity, and the trends are disappointing.

Will the people of the future become obese and lazy creatures, like the characters from the cartoon "Wally"? All in our hands. There are other points of view on this matter. The fact is that modern diets are high in fat and cheap “empty calories.” There is currently quite a negative attitude towards the problem of obesity, which will make people in the future better adjusted and picky eaters. With the popularization of the concept of proper nutrition, as well as with new technologies of “food of the future,” everything will fall into place. When humanity finally figures out healthy eating, it is likely that heart disease and diabetes, which are currently among the leading causes of death in developed countries, will disappear.

Hairline

Homo sapiens is often jokingly called a naked ape. But like all mammals, humans grow hair, of course, in much less quantity than our hominid cousins ​​and ancestors. Darwin, in The Descent of Man, stated that the hair on our bodies is a vestige. Due to the ubiquity of heating and affordable clothing, the previous purpose of body hair has become obsolete. But the evolutionary fate of hair is not easy to accurately predict, since it can act as one of the indicators of sexual selection. If the presence of body hair continues to be an attractive aspect to the opposite sex, then the gene responsible for it will remain in the population. But it is likely that people in the future will have much less hair than they do today.

Impact of technology

Computer technologies, which have become part of our daily lives, will undoubtedly affect the development of the human body. Constant use of keyboards and touch screens can cause our hands and fingers to become thinner, longer and more dexterous, and the number of nerve endings in them will increase dramatically. As the need to use technical interfaces increases, priorities will change. With further technical progress, interfaces (of course, not without surgical intervention) can migrate to the human body. Why shouldn’t a person of the future have a keyboard in the palm of his hand and learn to press the conventional OK button with a nod of his head, and answer an incoming call by connecting his index and thumb? It is likely that in this new world, the human body will be stuffed with hundreds of tiny sensors transmitting data to external devices. An augmented reality display can be built into the retina of the human eye, and the user will control the interface by moving the tongue along the front incisors.

Wisdom teeth and other rudiments

Vestigial organs such as wisdom teeth that are surgically removed may also disappear over time as they no longer serve their function. Our ancestors had larger jaws with more teeth. As their brains began to enlarge and their diets began to change and food became less tough and easier to digest, their jaws began to shrink. It was recently estimated that about 25% of people today are born without the rudiments of wisdom teeth, which may be a consequence of natural selection. This percentage will only grow in the future. It is possible that jaws and teeth will continue to become smaller and even disappear.

Poor memory and low intelligence

The theory that future people will have higher intellectual abilities is also questionable. A study from Columbia University shows that our dependence on Internet search engines greatly harms our memory. The Internet replaces our brain's ability to remember information that we can easily find on the Internet at any time. The brain began to use the Internet as a backup memory. “People are less likely to make the effort to remember something when they know they can always find that information later,” the study authors said.

Neuroscientist and Nobel Prize laureate Eric Kandel also points out in his article that the Internet is making people dumber. The main problem is that excessive use of the Internet does not allow you to concentrate on one thing. Mastering complex concepts requires paying serious attention to new information and diligently trying to associate it with knowledge already in memory. Surfing the Internet does not provide this opportunity: the user is constantly distracted and interrupted, which is why his brain is not able to establish strong neural connections.

As noted above, evolution follows the path of eliminating traits that are no longer needed. And one of them can be physical strength. Comfortable transport of the future, exoskeletons and other machines and tools of our ingenuity will save humanity from the need for walking and any physical activity. Research shows that we have already become much weaker compared to our distant ancestors. Over time, advances in technology may lead to changes in limbs. The muscles will begin to contract. The legs will become shorter and the feet smaller.

According to a recent study, the population of the United States is caught in a vicious cycle of constant stress and depression. Three in ten Americans say they are depressed. These symptoms are most common among people aged 45 to 65 years. 43% report regular outbursts of irritability and anger, 39% report nervousness and anxiety. Even dentists are seeing more patients with jaw pain and worn teeth than thirty years ago. Because of which?

Because of the stress, people clench their jaws tightly and literally grind their teeth in their sleep. Stress, as experiments on laboratory rats show, is a clear sign that the animal is becoming increasingly unfit for the world in which it lives. And as Charles Darwin and Alfred Russell Wallace astutely noted more than 150 years ago, when a living creature's habitat is no longer comfortable, the species goes extinct.

Weak immunity

Future people may have weakened immune systems and be more susceptible to pathogens. New medical technologies and antibiotics have greatly improved overall health and life expectancy, but have also made our immune systems lazier. We become more and more dependent on medications, and over time our bodies may stop “thinking” for themselves and instead rely entirely on medications to carry out basic bodily functions. Thus, people from the future may actually become slaves to medical technology.

Selective hearing

Humanity already has the ability to direct their attention to specific things they hear. This feature is known as the "cocktail effect". At a noisy party, among many conversations, you may well focus on one specific speaker who has attracted your attention for some reason. The human ear does not have a physical mechanism for this; everything happens in the brain.

But over time, this ability can become more important and useful. With the development of media and the Internet, our world is becoming overcrowded with various sources of information. The man of the future will have to learn to more effectively determine what is useful to him and what is just noise. As a result, people will be less susceptible to stress, which will undoubtedly benefit their health, and, accordingly, will take root in their genes.

Artist Nikolai Lamm and Dr. Alan Kwan presented their speculative view of how the person of the future will see. Researchers base their predictions on how the human body will be affected by the environment - that is, climate and technological advances. One of the biggest changes, in their opinion, will affect the forehead, which has become increasingly wider since the 14th century. The researchers also said that our ability to control our own genome will affect evolution. Genetic engineering will become the norm, and facial appearance will be increasingly determined by human preferences. Meanwhile, the eyes will become larger. Attempting to colonize other planets will result in darker skin to reduce exposure to harmful ultraviolet radiation outside of Earth's ozone layer. Kwan also expects people to have thicker eyelids and pronounced brow ridges due to low-gravity conditions.

Post-gender society

With the development of reproductive technologies, reproduction in the traditional way may disappear into oblivion. Cloning, parthenogenesis and the creation of artificial wombs can significantly expand the potential for human reproduction, and this in turn will completely erase the boundaries between men and women. People of the future will not be attached to a particular gender, enjoying the best aspects of life as both. It is likely that humanity will completely intermingle, forming a single androgynous mass. Moreover, in the new post-gender society, not only will there be no physical genders or their supposed signs, gender identity itself will be eliminated and the line between the role models of behavior of men and women will be erased.

Many creatures, such as fish and sharks, have a lot of cartilage in their skeletons. Human beings could follow the same developmental path to develop more flexible bones. Even if not thanks to evolution, but with the help of genetic engineering, this feature would provide a lot of advantages and protect a person from injury. A more flexible skeleton would obviously be extremely useful in childbirth, not to mention its potential for future ballet dancers.

Wings

As Guardian columnist Dean Burnett writes, he once spoke to a colleague who doesn't believe in evolution. When he asked why, the main argument was that people do not have wings. According to the opponent, “evolution is the survival of the fittest,” and what could be more convenient for adapting to any environment than wings. Even if Burnett's theory on this matter is based on immature observations and a limited understanding of how evolution works, it also has its right to exist.

Anthropogenesis (from the Greek anthropos - man + genesis - origin) is the process of historical formation. Today there are three main theories of anthropogenesis.

Creation theory, the oldest in existence, states that man is the creation of a supernatural being. For example, Christians believe that man was created by God in a one-time act “in the image and likeness of God.” Similar ideas are present in other religions, as well as in most myths.

Evolutionary theory states that man evolved from ape-like ancestors in a process of long development under the influence of the laws of heredity, variability and natural selection. The foundations of this theory were first proposed by the English naturalist Charles Darwin (1809-1882).

Space theory claims that man is of extraterrestrial origin. He is either a direct descendant of alien creatures, or the fruit of experiments by extraterrestrial intelligence. According to most scientists, this is the most exotic and least likely of the mainstream theories.

Stages of human evolution

With all the diversity of points of view on anthropogenesis, the vast majority of scientists adhere to the evolutionary theory, which is confirmed by a number of archaeological and biological data. Let us consider the stages of human evolution from this point of view.

Australopithecus(Australopithecus) is considered to be the closest to the ancestral form of humans; he lived in Africa 4.2-1 million years ago. Australopithecus's body was covered with thick hair, and in appearance it was closer to a monkey than to a human. However, he already walked on two legs and used various objects as tools, which was facilitated by the spaced big toe. Its brain volume (relative to body volume) was smaller than that of a human, but larger than that of modern apes.

A skilled man(Homo habilis) is considered the very first representative of the human race; he lived 2.4-1.5 million years ago in Africa and was named so because of his ability to make simple stone tools. His brain was one third larger than that of Australopithecus, and the biological features of the brain indicate possible rudiments of speech. In other respects, Homo habilis was more similar to Australopithecus than to modern humans.

Homo erectus(Homo erectus) settled 1.8 million - 300 thousand years ago throughout Africa, Europe and Asia. He made complex tools and already knew how to use fire. His brain is close in volume to the brain of modern humans, which allowed him to organize collective activities (hunting large animals) and use speech.

In the period from 500 to 200 thousand years ago, the transition from Homo erectus to Homo sapiens took place. It is quite difficult to detect the boundary when one species replaces another, so representatives of this transitional period are sometimes called the oldest homo sapiens.

Neanderthal(Homo neanderthalensis) lived 230-30 thousand years ago. The volume of the Neanderthal brain was similar to the modern one (and even slightly exceeded it). Excavations also indicate a fairly developed culture, which included rituals, the beginnings of art and morality (caring for fellow tribesmen). Previously, it was believed that Neanderthal man was the direct ancestor of modern man, but now scientists are inclined to believe that he is a dead-end, “blind” branch of evolution.

reasonable new(Homo sapiens sapiens), i.e. modern humans appeared about 130 thousand (possibly more) years ago. The fossils of the “new people” were called Cro-Magnons after the place of their first discovery (Cro-Magnon in France). Cro-Magnons looked little different from modern humans. They left behind numerous artifacts that allow us to judge the high development of their culture - cave painting, miniature sculpture, engravings, jewelry, etc. Thanks to his abilities, Homo sapiens populated the entire Earth 15-10 thousand years ago. In the course of improving the tools of labor and accumulating life experience, man moved to a producing economy. During the Neolithic period, large settlements arose, and humanity entered the era of civilizations in many areas of the planet.

Human evolution is a theory of the origin of people created by the English naturalist and traveler Charles Darwin. He claimed that the ancient one descended from a monkey. To confirm his theory, Darwin traveled a lot and tried to collect different ones.

It is important to emphasize here that evolution (from the Latin evolutio - “unfolding”), as a natural process of development of living nature, accompanied by a change in the genetic composition of populations, really takes place.

But regarding the emergence of life in general and the emergence of man in particular, evolution is rather meager in scientific evidence. It is no coincidence that it is still considered just a hypothetical theory.

Some tend to believe in evolution, considering it the only reasonable explanation for the origin of modern people. Others completely deny evolution as an unscientific thing, and prefer to believe that man was created by the Creator without any intermediate options.

So far, neither side has been able to scientifically convince opponents that they are right, so we can confidently assume that both positions are based purely on faith. What do you think? Write about it in the comments.

But let's understand the most common terms associated with the Darwinian idea.

Australopithecus

Who are Australopithecus? This word can often be heard in pseudo-scientific conversations about human evolution.

Australopithecus (southern monkeys) are upright descendants of Dryopithecus, who lived in the steppes of Africa about 4 million years ago. These were quite highly developed primates.

A skilled man

It was from them that the most ancient species of people originated, whom scientists call Homo habilis - “skillful man.”

The authors of the theory of evolution believe that in appearance and structure, Homo habilis did not differ from apes, but at the same time he was already able to make primitive cutting and chopping tools from roughly processed pebbles.

Homo erectus

The fossil species of people Homo erectus (“upright man”), according to the theory of evolution, appeared in the East and already 1.6 million years ago spread widely throughout Europe and Asia.

Homo erectus was of average height (up to 180 cm) and had a straight gait.

Representatives of this species learned to make stone tools for work and hunting, used animal skins as clothing, lived in caves, used fire and cooked food on it.

Neanderthals

The Neanderthal (Homo neanderthalensis) was once considered the ancestor of modern humans. This species, according to the theory of evolution, appeared about 200 thousand years ago, and ceased to exist 30 thousand years ago.

Neanderthals were hunters and had a powerful physique. However, their height did not exceed 170 centimeters. Scientists now believe that Neanderthals were most likely just a side branch of the evolutionary tree from which man originated.

Homo sapiens

Homo sapiens (in Latin - Homo sapiens) appeared, according to Darwin's theory of evolution, 100-160 thousand years ago. Homo sapiens built huts and huts, sometimes even living pits, the walls of which were lined with wood.

They skillfully used bows and arrows, spears and bone hooks to catch fish, and also built boats.

Homo sapiens was very fond of painting his body and decorating clothes and household items with drawings. It was Homo sapiens who created human civilization, which still exists and develops today.

It should be said that this entire evolutionary chain of human origin is exclusively Darwin’s theory, which still has no scientific evidence. does not have information that even in such ancient civilizations as there were at least some hints of the monkey as the ancestor of man.

Charles Darwin himself perfectly understood the absolute hypothetical nature of his judgments, which he wrote about more than once. With all this, one cannot help but pay tribute to this naturalist, who nevertheless tried to explain the origin of man through natural selection and evolution.

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