There were upright posture, an increase in the volume of the brain and the complication of its organization, the development of the hand, the lengthening of the period of growth and development. A developed hand with a well-pronounced grasping function allowed a person to successfully use and then make tools. This gave him advantages in, although in his purely physical qualities he was significantly inferior to animals. The most important milestone in human development was the acquisition of the ability to first use and maintain, and then make fire. The complex activity of making tools, obtaining and maintaining fire could not be provided by innate behavior, but required individual behavior. Therefore, there was a need for a significant expansion of the possibility of signal exchange and a speech factor appeared that fundamentally distinguishes humans from other animals. The emergence of new functions, in turn, contributes to accelerated development. Thus, the use of hands for hunting and protection and eating food softened on fire made the presence of powerful jaws unnecessary, which made it possible to increase the volume of the cerebral part of the skull due to its facial part and ensure further development mental abilities person. The emergence of speech contributed to the development of more perfect structure society, the division of responsibilities between its members, which also gave advantages in the struggle for existence. Thus, the factors of anthropogenesis can be divided into biological and social.

Biological factors - hereditary variability, as well as the mutation process, isolation - are applicable to. Under their influence, in the process of biological evolution, morphological changes occurred in the ape-like ancestor - anthropomorphosis. The decisive step on the way from ape to man was bipedalism. This led to the release of the hand from the functions of movement. The hand begins to be used to perform various functions - grabbing, holding, throwing.

No less important prerequisites for anthropogenesis were the features of the biology of human ancestors: a herd way of life, an increase in brain volume in relation to the general proportions of the body, binocular vision.

The social factors of anthropogenesis include labor activity, social lifestyle, development of speech and thinking. Social factors began to play a leading role in anthropogenesis. However, the life of each individual is subject to biological laws: mutations are preserved as a source of variability, stabilizing selection acts, eliminating sharp deviations from the norm.

Factors of anthropogenesis

1) Biological

natural selection against the backdrop of the struggle for existence
genetic drift
insulation
hereditary variability
2) Social

public life
consciousness
speech
labor activity
In the early stages of human evolution, the dominant role was played by biological factors, and on the latter - social. Labor, speech, consciousness are most closely connected with each other. In the process of labor, the members of society were united and fast development way of communication between them, which is speech.

The common ancestors of humans and great apes - small arboreal insectivorous placental mammals lived in the Mesozoic. In the Paleogene of the Cenozoic era, a branch separated from them, which led to the ancestors of modern great apes - parapithecus.

Parapithecus Dryopithecus Pithecanthropus Sinanthropus Neanderthal Cro-Magnon modern man.

Analysis of paleontological finds allows us to identify the main stages and directions historical development man and great apes. modern science gives the following answer: humans and modern great apes had a common ancestor. Further, their development followed the path of divergence (divergence of features, accumulation of differences) in connection with specific and different conditions of existence.

human pedigree

Insectivorous mammals parapithecus:

Propliopithecine, Orangutan
Dryopithecus Chimpanzee, Australopithecus Ancient people (Pithecanthropus, Sinanthropus, Heidelberg man) Ancient people (Neanderthals) New people (Cro-Magnon, modern man
We emphasize that the human genealogy presented above is hypothetical. We also recall that if the name of the ancestral form ends in "pithek", then we are talking about a still monkey. If at the end of the name is “anthrope”, then we have a person in front of us. True, this does not mean that signs of an ape are necessarily absent in its biological organization. It must be understood that the signs of a person in this case prevail. From the name "Pithecanthropus" it follows that this organism has a combination of signs of ape and man, and in approximately equal proportions. Let's give brief description some of the supposed ancestral forms of man.

DRIOPITEK

He lived about 25 million years ago.

Characteristic features of development:

much smaller than a person (height is about 110 cm);
led a predominantly arboreal lifestyle;
probably manipulated objects;
tools are missing.
australopithecines

Lived about 9 million years ago

Characteristic features of development:

height 150–155 cm, weight up to 70 kg;
skull volume - about 600 cm3;
probably used objects as tools for food and protection;
upright posture is characteristic;
the jaws are more massive than in humans;
strongly developed superciliary arches;
joint hunting, herd way of life;
often ate the remains of the prey of predators
Pithecanthrope

Lived approximately 1 million years ago

Characteristic features of development:

height 165–170 cm;
brain volume about 1100 cm3;
constant upright posture; speech formation;
mastery of fire
SINANTROP

Lived probably 1-2 million years ago

Characteristic features of development:

height about 150 cm;
upright posture;
making primitive stone tools;
maintaining the fire;
public lifestyle; cannibalism
NEANDERTHAL

Lived 200–500 thousand years ago

Characteristic signs:

Biological:

height 165–170 cm;
brain volume 1200–1400 cm3;
the lower limbs are shorter than in modern humans;
the femur is strongly curved;
low sloping forehead;
strongly developed brow ridges
Social:

lived in groups of 50–100 individuals;
used fire;
made a variety of tools;
built hearths and dwellings;
carried out the first burials of the dead brothers;
speech is probably more perfect than that of Pithecanthropus;
perhaps the emergence of the first religious beliefs; skilled hunters;
cannibalism persisted
Cro-Magnon

Lived 30–40 thousand years ago

Characteristic signs:

Biological:

height up to 180 cm;
brain volume about 1600 cm3;
there is no continuous supraorbital ridge;
dense physique;
developed muscles
Social:

lived in a tribal community;
built settlements;
made complex tools of labor from bone and stone;
knew how to grind, drill;
deliberately buried the dead brothers;
rudimentary religious ideas appear;
developed articulate speech;
wore clothes made of skins;
purposeful transfer of experience to descendants;
sacrificed himself in the name of the tribe or family;
cared for the elderly;
the emergence of art;
domestication of animals;
first steps in farming
MODERN MAN

Lives on all continents

Characteristic signs:

Biological:

height 160–190 cm;
brain volume about 1600 cm3;
having different races
Social:

sophisticated tools;
high achievements in science, technology, art, education

Factors of human evolution

In the early stages of human evolution dominated biological factors evolution - variability, struggle for existence, natural selection, etc.

In the later stages of human evolution, the main social factors evolution - a social way of life, the use of tools, the use of fire, the development of speech.

Stages of human evolution

Races

These are divisions within a species adapted to specific conditions. Races are found in all widespread species. In humans, 3 large races are distinguished (Negroids, Caucasians, Mongoloids).

Racist theory (racism) rejects the unity of the human races, i.e. claims that different races of man are descended from different ancestors. This is not true, all human races easily interbreed and give fertile offspring, i.e. belong to the same species.

Differences between humans and apes

Speech, chin protrusion.

Second signaling system , large brain, the brain part of the skull is larger than the front.

Labor activity(creation and use of tools), the thumb is opposed to the rest and well developed.

bipedalism: arched foot, extended pelvis, curves in the spine (S-shaped spine), chest expanded to the sides.

Answer

Choose the one most correct option. The racial theory is based on the denial
1) similarities between humans and anthropoids
2) the unity of the origin of human races
3) human belonging to primates
4) morphological unity of races

Answer

Choose three options. Man is different from animals
1) has a bark hemispheres
2) forms various natural populations
3) has a second signal system
4) can create an artificial habitat
5) has the first signal system
6) can create and use tools

Answer

Choose three options. What characteristics of mammals are NOT characteristic of humans?
1) the presence of a diaphragm
2) the presence of undercoat
3) the presence of seven cervical vertebrae
4) tail section of the body
5) movable auricle
6) alveolar lung

Answer

Choose three options. Man, unlike animals
1) affects the environment in the process of life
2) has an S-shaped spine
3) forms various populations
4) has the first signal system
5) has a second signal system
6) creates and uses tools

Answer

Choose three options. In humans, unlike mammals
1) the body is vertical
2) the spine does not have bends
3) the spine forms four smooth bends
4) the chest is expanded to the sides
5) the chest is compressed from the sides
6) the facial part of the skull prevails over the brain

Answer

Choose one, the most correct option. The second human signaling system is
1) conditioned reflexes
2) unconditioned reflexes
3) speech
4) instincts

Answer

1. Establish a correspondence between the example and the anthropogenesis factor that illustrates it: 1) biological, 2) social
A) spatial isolation
B) genetic drift
B) speech
D) abstract thinking
D) social labor activity
E) population waves

Answer

2. Establish a correspondence between the example and the factor of anthropogenesis for which it is characteristic: 1) biological, 2) social
A) work activity
B) abstract thinking
B) isolation
D) mutational variability
D) population waves
E) second signaling system

Answer

Choose three options. Which of the following features characterize the social factors of human evolution?
1) public lifestyle
2) the ability to transmit acquired traits by inheritance
3) abstract thinking and speech
4) joint labor activity
5) modification variability
6) natural selection and care for offspring

Answer

Indicate the historical sequence of the main stages of anthropogenesis
1) Modern man
2) Australopithecus
3) Cro-Magnon
4) Pithecanthropus
5) Neanderthal

Answer

Set the chronological sequence of anthropogenesis
1) skillful person
2) Homo erectus
3) driopithecus
4) a reasonable person

Answer

Choose three features of the skeleton that are unique to humans
1) the presence of clavicles
2) the presence of a chin protrusion
3) lightening the bone mass of the upper limbs
4) the presence of five-fingered limbs
5) S-shape of the spinal column
6) arched foot

Answer

1. Choose three options. In connection with upright posture in humans
1) upper limbs are released
2) the foot becomes arched
3) the thumb is opposed to the rest
4) the pelvis expands, its bones grow together
5) the brain region of the skull is smaller than the facial
6) hairline decreases

Answer

2. Choose three correct answers from six and write down the numbers under which they are indicated. The adaptations of a person to walking upright are the following signs:
1) the human spinal column has acquired distinct bow-shaped bends, two of which are directed forward, the other two are backward
2) the thumb is opposed to all the rest
3) development of the cerebral cortex
4) the formation of the arched structure of the foot
5) rotation of the pelvis and its sharp expansion
6) the presence of a diaphragm

Answer

3. Choose three correct answers from six and write down the numbers under which they are indicated. In humans, due to upright posture
1) the spine forms four bends
2) the bones in the joints are connected movably
3) the fingers of the hand are connected to the metacarpus
4) the belt of the lower extremities is wide, has the form of a bowl
5) arch is well expressed in the foot
6) the thumb is opposed to all the rest

Answer

4. Choose three correct answers from six and write down the numbers under which they are indicated. In humans, due to upright posture
1) the spine has S-shape
2) the chest is flattened from the sides
3) the belt of the lower extremities is bowl-shaped
4) the mass of the vertebral bodies decreases from the cervical to the lumbar
5) the arch of the foot has formed
6) the bones of the upper limbs are more massive

Answer

Choose three options. The human skeleton, unlike the skeleton of mammals, has
1) straight spine without bends
2) chest, compressed in the dorsal-abdominal direction
3) chest, compressed from the sides
4) S-shaped spine
5) arched foot
6) massive facial part of the skull

Answer

Choose three options. What are the similarities between the human skeleton and the skeletons of mammals?
1) the spine has five sections
2) the foot has an arch
3) the cerebral part of the skull is larger than the facial
4) there are paired articular limbs
5) in cervical region seven vertebrae
6) the shape of the spine is S-shaped

Answer

Establish the sequence of evolution of fossil ancestors modern man in chronological order. Write down the corresponding sequence of numbers.
1) African Australopithecus
2) reasonable Neanderthal man
3) Pithecanthropus
4) driopithecus (xeniapithecus)
5) skillful person

Answer

1. Choose three correct answers out of six and write down in the answer the numbers under which they are indicated. In a person, in connection with labor activity, the following species features:
1) fine motor skills of hands
2) abstract thinking and speech
3) bowl-shaped pelvis
4) S-shaped spine
5) arched foot
6) a significant increase in the size of the brain

Answer

2. Choose three options. What features have been formed in a person in connection with labor activity?
1) arched foot
2) development of the clavicles in the shoulder girdle
3) bowl-shaped pelvis
4) complication of the cerebral cortex
5) opposition thumb hands to everyone else
6) speech and thinking

Answer

Choose one, the most correct option. The adaptability of a person to work activity is manifested in
1) movable connection of bones
2) the presence of different parts of the brain
3) the presence of five fingers
4) Diversity of hand functions

Answer

Analyze the table "Differences in the structure of man and great apes." For each cell marked with a letter, select the appropriate term from the list provided. Write down the chosen numbers, in the order corresponding to the letters.
1) the facial part of the skull predominates, there are solid superciliary ridges, there is no chin protrusion, the brain volume is about 700 cm3
2) the arms are longer than the legs, the big toe is opposed to the rest, there is an arch of the foot
3) chest
4) cervical and lumbar spine
5) the facial part of the skull predominates, there are superciliary arches, the chin protrusion is poorly developed, the brain volume is about 1100 cm3
6) thoracic and sacral spine
7) legs longer than arms, the thumb is opposed to the rest, the foot is arched
8) spine

Answer

Set the chronological sequence of the stages of anthropogenesis. Write down the corresponding sequence of numbers.
1) Australopithecus
2) skillful person
3) Homo erectus
4) Neanderthal
5) Cro-Magnon

Answer

Choose one, the most correct option. What feature of a person was formed under the influence of biological factors of anthropogenesis?
1) making tools
2) joint work
3) the appearance of the diaphragm
4) arched foot

Answer

Establish a correspondence between the signs and representatives of the class Mammals, for which these signs are characteristic: 1) an ordinary chimpanzee, 2) a reasonable person. Write down the numbers 1 and 2 in the order corresponding to the letters.
A) the predominance of the facial part of the skull over the brain
B) the belt of the lower extremities in the form of a bowl
B) arched foot
D) the presence of a chin protrusion
D) developed superciliary arches
E) laterally compressed chest

Answer

© D.V. Pozdnyakov, 2009-2019

Do you think the principles that explain the origin and evolution of animal species are applicable to explain the origin and evolution of humans? From the point of view of the synthetic theory, the biological factors of the evolution of the organic world - the mutation process, the waves of life, the drift of genes, isolation, the struggle for existence and natural selection - are also applicable to human evolution. The cooling of the climate and the displacement of forests by steppes led to the transition of the ancestors of great apes to a terrestrial way of life. This fact was the first step on their way to bipedalism.

Shortcomings in the speed of movement during upright walking were made up for by the fact that the forelimbs were freed. At the same time, the vertical position of the body made it possible to obtain more information. For example, human ancestors could react more timely to the approach of predators. Hands began to be used for the manufacture and use of various tools. Since the listed devices were aimed at increasing survival, it was along this path that further action was carried out. natural selection. Consequently, the biological factors of anthropogenesis contributed to the formation of morphophysiological features of a person (upright walking, an increase in brain volume, a developed hand).

Role social factors in anthropogenesis was revealed by F. Engels in his work “The Role of Labor in the Process of the Transformation of Apes into Humans” (1896). It is logical to arrange the social factors of evolution in the following sequence: joint way of life → thinking → speech → labor → social way of life. Human ancestors began to unite in groups for living together, mastered the manufacture of tools. It is the manufacture of tools that is a clear boundary between ape-like ancestors and humans. In the struggle for existence, groups of individuals began to gain an advantage, which together could withstand adverse environmental conditions. Thus, the social factors of anthropogenesis were aimed at improving the relationship between people within the group.

The role of labor in the formation of man

The evolution of the hand after being freed from the support function went in the direction of its improvement for labor activity. This fact is reflected in the manufacture of various tools. This was noted when studying the fossil remains of Homo habilis ( Homo habilis).

The structure of the bones of the hand Homo habilis indicates a well-developed grasping ability of the upper limb. The nail phalanges have become short and flat, which once again emphasizes active use brushes. Expanded phalanges of the fingers are evidence of severe physical work. In addition, the hand has become the leading human organ in making contacts at a distance with the help of various objects.

The use of manufactured hunting tools significantly increased the efficiency of this process. A person, along with plant foods, began to widely include in the diet more high-calorie foods of animal origin. Cooking food on fire reduced the load on the chewing apparatus and the digestive system. As a result, the skeleton of the head became lighter, the intestines shortened.

With the development of labor activity, there was a further unification of people for life together. This expanded the concept of man about the world around him. New ideas were generalized in the form of concepts, which contributed to the development of thinking and the formation of articulate speech. With the improvement of speech, the development of the brain went on. It was in these directions that the action of the driving form of natural selection was realized. As a result, the volume of the brain increased significantly in ancient people in a very short period of time.

Public lifestyle as a factor in human evolution

During the transition to a terrestrial way of life, human ancestors faced a number of difficulties in the struggle for existence. This is the development of new habitats, and the constant danger associated with predators in open spaces. For successful survival, human ancestors united in groups, and labor contributed to the rallying of their members. Ancient people collectively defended themselves from predators, hunted and raised children. The older members taught the younger ones to seek out natural materials and make tools, taught to hunt and maintain fire. The use of fire, in addition to cooking, helped protect against bad weather and predators.

Public life provided unlimited opportunities for communication through sounds and gestures. Gradually undeveloped larynx and oral apparatus ape-like ancestors turned into organs of human articulate speech. This was facilitated by hereditary variability and natural selection.

The leading role of social factors in the history of human development

At the stage of evolution of the most ancient people, the leading role belonged to biological factors - the struggle for existence and natural selection. The selection was aimed at the survival of individual populations of people. The most adapted to adverse conditions and more skilled in the manufacture of tools survived. As people united into groups, social factors began to play a leading role in anthropogenesis. The advantage in the struggle for existence did not necessarily go to the strongest. Gradually, the herd and the forms of communication associated with it became the object of selection. Those who preserved children as much as possible - the future of the population and the elderly - the bearers of life experience, survived.

Through labor and speech, a person began to gradually master the culture of the production of tools, the construction of dwellings. Training and education, as well as the transfer of experience, were an important prerequisite for the emergence of elements of human culture. Initially, they appeared in the form of rock paintings, figurines, and funeral rites. The improvement of the collective way of life, the distribution of responsibilities between members of the group reduced the role of biological factors in human evolution.

Qualitative differences of a person

Speaking of qualitative differences, let us try to summarize the preconditions of anthropogenesis discussed earlier. A skilled man, the first true representative of the family Homo, distinguishes from representatives of the animal world precisely the ability to make tools.

It is the manufacture that is important here, and not the mere use of a stick or stone by ape-like ancestors to satisfy needs for protection or food. Animals can also use improvised means to obtain food. Monkeys, for example, knock bananas and coconuts off palm trees with sticks and stones. Sea otters use stones to crack shells of mollusks. Some species of Galapagos finches use cactus spines to get insects from under the bark of trees.

All ways of using objects in the life of animals are random or caused by instincts. Therefore, the main qualitative difference of a person is, of course, conscious work. It is labor that is the boundary that separated man and his distant ancestors.

Man has the same body plan as all mammals. At the same time, there are a number of differences in the structure of the human body related to upright posture, labor activity and the development of speech.

In connection with upright posture the position of the body changed and the center of gravity shifted to the lower extremities. This led to a change in the shape of the spine from arched to S-shaped. This shape gave the spine additional flexibility when moving. The shortening of the spinal column ensures a stable position of the body on the lower limbs, which in humans, unlike ape-like ancestors, are longer than the upper ones.

Other progressive elements associated with walking on two legs were: an arched, springy foot, an expanded pelvis, as well as a shorter and wider chest. The foramen magnum in humans moves to the center of the base of the skull, which allows the skull to be balanced on the cervical vertebrae.

In connection with labor activity man's hand has small size, characterized by subtlety and mobility. This gives her the ability to perform a variety of movements. Leading the thumb to the side and opposing it to the rest allows a person not only to take an object, but also to comfortably grasp it.

The increase in brain volume led to an increase in the size of the brain region of the skull, on average, up to 1500 cm 3 . In terms of volume, it exceeds the facial region by 4 times, although in monkeys this ratio is 1: 1.

WITH speech development the lower jaw of a person took on the appearance of a horseshoe with a protruding chin. Another distinguishing feature was the presence of a second signal system. The word and the thinking associated with it allow a person to reason logically and generalize the accumulated facts. This is the basis for the transfer of experience, culture, traditions, knowledge over many generations. The knowledge and experience accumulated by a person during his life become the property of the whole society. This became possible thanks to the development of speech, and later - writing.

Such qualities of a person as hard work, plasticity of thinking, culture of speech develop on the basis of education and upbringing in society. Outside of human society, the formation of a harmoniously developed personality is impossible.

Human evolution is based on biological (mutation process, waves of life, genetic drift, isolation, struggle for existence, natural selection) and social (labor, thinking, speech, social life) factors of evolution. Labor contributed to the unification of human ancestors into groups. The development of speech, the improvement of the collective way of life, the distribution of duties among the members of the group - all this strengthened the role of social factors of anthropogenesis. The word and the thinking associated with it allowed a person to reason logically and generalize the accumulated facts. hallmark human is the presence of a second signaling system.

Biological factors influence human evolution.

Human development historically could not take place in isolation from the surrounding reality. This process was influenced by the biological factors of human evolution, the same as they influenced the rest of wildlife. However, studies show that only biological factors are clearly not enough for anthropogenesis, social factors were also required.

The early stages of human evolution are characterized by the predominance of biological factors. Of decisive importance was the natural selection of individuals with better adaptability to constantly changing environmental conditions.

There was a selection and individuals who showed the ability to produce primitive tools, without which the extraction of food and protection from enemies became problematic.

At later stages, selection was already carried out on the basis of herding and related forms of communication. In the environment, only groups of individuals could continue to exist, capable of jointly resisting surprises and adverse factors.

On certain stages The biological factors of human evolution also included individual selection, which was based on the selective death of individual individuals and contributed to the formation of morphophysiological features of a person, such as upright posture, a large brain, and a developed hand.

Man already had a difference from the surrounding animal world in that he could speak, developed thinking and the ability to work. Thus, in the process of anthropogenesis, modern man was formed.

The biological factors of the historical-revolutionary process of the formation of man were exactly the same for all living nature. They became especially important in the early stages of human development. Charles Darwin wrote a lot about the role of biological factors for human evolution.

The biological factors of human evolution have created the prerequisites for the occurrence of hereditary changes in him, which determine, for example, eye and hair color, height, and the body's resistance to influences. external environment.

Man's dependence on nature was especially felt in the early stages of his evolution. Only individuals who were characterized by endurance, physical strength, dexterity, quick wit and other useful qualities could survive and leave offspring for procreation.

The beginning of the improvement of labor tools significantly reduced the role of biological evolution. Technogenic evolution has forced a person not to wait, as they say, for alms from nature. He no longer adapted painfully and slowly, but he himself consciously changed himself. surrounding nature and forced her to satisfy her needs. To do this, people used powerful tools.

Nevertheless, the biological factors of human evolution have not completely lost their influence on the animal world in general, and on humans in particular. Nature is still the cause of the ongoing evolution of man.

The monkeys did not start walking right away. The change in the environment - the transition from forests to live in open areas caused some of them to have an upright posture, which was preserved and improved over millions of years in the process of the struggle for existence and natural selection. Bipedalism limited the motor activity of great apes, which led to the fusion and immobility of the bones of the sacrum. And this, although it made childbirth somewhat difficult, made it possible to see the approaching danger from afar, and freed up hands for making tools.

At the beginning of the process of forming a person, his hands were not yet well developed and performed only simple movements. Thanks to mutational variability, the struggle for existence and natural selection, individuals with modified hands were preserved, capable of performing labor operations. It took millions of years for the first great apes to be able not only to use ready-made objects (stones, sticks) as tools, but also to learn how to make them. The creation of tools led to the emergence of ever greater differences between the hands of humans and monkeys and reduced its dependence on the external environment. This is exactly what F. Engels had in mind when he noted that man was created by labor.

Living in a community played an important role in the process of turning apes into humans. Any individual with a tool could not alone resist the attack of predatory animals. Therefore, the most ancient and ancient people began to live in communities. Thus, they defended themselves from predatory animals, hunted, raised children. The elders of the community taught the young members how to make tools, how to hunt, keep fire, and find edible plants and animals.

Ancient people formed primitive communal relations, namely, care for the wounded and sick members of the community, the funeral of the dead. The community consisted of 50-100 people. Living in the community was of great importance. Communities survived that were able to resist in the struggle for existence, hunt well, provide themselves with food, take care of each other, help reduce mortality among the elderly and children, and overcome unfavorable living conditions. The rest of the communities perished.

With development labor process the usefulness of mutual assistance became more and more obvious. The experience that people have accumulated by knowing environment, nature in general, was passed down from generation to generation and improved. Living in a community allowed its members to communicate with each other using sounds, gestures and facial expressions. As a result of hereditary variability and natural selection, the gore-tan and mouth apparatus, which were not gradually developed in monkeys, turned into a speech organ in humans. material from the site

Man and higher animals react to external objects and events with the direct participation of vision, hearing and other sense organs. Unlike higher animals, humans have a second signaling system. A person perceives external signals through words. This is a sign that qualitatively distinguishes the higher nervous activity of man and animals from each other. Thanks to speech, joint work developed public relations that strengthened human interaction.

In the process of the emergence of man, the consumption of food cooked on fire also played an important role. Hunting and fishing made it possible to eat not only vegetable, but also mixed food, which in itself was the reason for the reduction in the length of the intestine. Over the millennia, the consumption of fire-cooked food gradually eased the load on the masticatory apparatus, as a result of which the rib of the upper bone, which connects the powerful masticatory muscles in monkeys, lost its biological significance.