EntranceSocial factors of human evolution. Factors of human evolution
Factors of human evolution
The early stages of human evolution were dominated by biological factors evolution - variability, struggle for existence, natural selection, etc.
In the later stages of human evolution, the main social factors evolution - social way of life, use of tools, use of fire, development of speech.
Stages of human evolution
Races
These are divisions within a species, adapted to specific conditions. All widespread species have races. In humans, there are 3 large races (Negroids, Caucasians, Mongoloids).
Racist theory (racism) rejects the unity of human races, i.e. states that different races of man are descended from different ancestors. This is not true, all human races easily interbreed and produce fertile offspring, i.e. belong to the same species.
Differences between humans and apes
Speech, chin protuberance.
Second signaling system, large brain, the cerebral part of the skull is larger than the facial part.
Labor activity(creation and use of tools), the thumb is opposed to the rest and is well developed.
Upright walking: arched foot, widened pelvis, curves in the spine (S-shaped spine), chest expanded to the sides.
Answer
Choose one, the most correct option. The basis of racial theory is denial
1) similarities between humans and anthropoids
2) unity of origin of human races
3) human belonging to primates
4) morphological unity of races
Answer
Choose three options. Man versus animals
1) has a cerebral cortex
2) forms different natural populations
3) has a second signaling system
4) can create an artificial habitat
5) has a first signaling system
6) can create and use tools
Answer
Choose three options. Man, unlike animals
1) affects the habitat in the process of life activity
2) has an S-shaped spine
3) forms different populations
4) has a first signaling system
5) has a second signaling system
6) creates and uses tools
Answer
Choose three options. In humans, unlike mammals
1) the body is located vertically
2) the spine has no bends
3) the spine forms four smooth curves
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 includes
1) conditioned reflexes
2) unconditioned reflexes
3) speech
4) instincts
Answer
1. Establish a correspondence between the example and the factor of anthropogenesis that illustrates it: 1) biological, 2) social
A) spatial isolation
B) genetic drift
B) speech
D) abstract thinking
D) social work 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 characteristics characterize the social factors of human evolution?
1) social way of life
2) the ability to transmit acquired characteristics by inheritance
3) abstract thinking and speech
4) joint work activity
5) modification variability
6) natural selection and care for offspring
Answer
Indicate the historical sequence of the main stages of anthropogenesis
1) Man of the modern type
2) Australopithecus
3) Cro-Magnon
4) Pithecanthropus
5) Neanderthal
Answer
Establish the chronological sequence of anthropogenesis
1) a skilled person
2) homo erectus
3) Dryopithecus
4) a reasonable person
Answer
Select three skeletal features that are unique to humans
1) presence of clavicles
2) the presence of a chin protuberance
3) relief of bone mass of the upper limbs
4) the presence of five-fingered limbs
5) S-shaped spinal column
6) arched foot
Answer
1. Choose three options. In connection with upright posture in humans
1) upper limbs are freed
2) the foot takes on a arched shape
3) the thumb is opposed to the rest
4) the pelvis expands, its bones grow together
5) the cerebral part of the skull is smaller than the facial part
6) hair loss
Answer
2. Choose three correct answers out of six and write down the numbers under which they are indicated. Human adaptations to walking upright are the following:
1) the human spinal column has acquired distinct bow-shaped curves, two of which are directed forward, the other two - backward
2) the thumb is opposed to all the others
3) development of the cerebral cortex
4) formation of an arched foot structure
5) rotation of the pelvis and its sharp expansion
6) presence of a diaphragm
Answer
3. Choose three correct answers out of six and write down the numbers under which they are indicated. In humans, due to upright posture
1) the spine forms four curves
2) the bones in the joints are movably connected
3) the fingers of the hand are connected to the metacarpus
4) the belt of the lower extremities is wide, has the shape of a bowl
5) the arch is well defined in the foot
6) the thumb of the hand is opposed to all the others
Answer
4. Choose three correct answers out of six and write down the numbers under which they are indicated. In humans, due to upright posture
1) the spine is S-shaped
2) the chest is flattened laterally
3) bowl-shaped belt of the lower extremities
4) the mass of the vertebral bodies decreases from the cervical to the lumbar region
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 dorso-abdominal direction
3) chest, compressed laterally
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 part
4) there are paired articular limbs
5) there are seven vertebrae in the cervical region
6) S-shaped spine
Answer
Establish the sequence of evolution of the fossil ancestors of modern humans in chronological order. Write down the corresponding sequence of numbers.
1) Australopithecus africanus
2) Homo sapiens Neanderthal
3) Pithecanthropus
4) Dryopithecus (Xeniapithecus)
5) a skillful person
Answer
1. Choose three correct answers out of six and write down the numbers under which they are indicated in the answer. In humans, in connection with work activity, the following specific characteristics have formed:
1) fine motor skills
2) abstract thinking and speech
3) cup-shaped pelvis
4) S-shaped spine
5) arched foot
6) significant increase in brain size
Answer
2. Select three options. What characteristics have developed in a person in connection with work?
1) arched foot
2) development of the clavicles in the shoulder girdle
3) cup-shaped pelvis
4) complication of the cerebral cortex
5) opposition of the thumb to all the others
6) speech and thinking
Answer
Choose one, the most correct option. A person’s adaptability to work is manifested in
1) movable bone connection
2) the presence of different parts of the brain
3) the presence of five fingers
4) variety of hand functions
Answer
Analyze the table “Differences in the structure of humans and apes.” For each cell indicated by a letter, select the corresponding term from the list provided. Write down the selected numbers in the order corresponding to the letters.
1) the facial part of the skull predominates, there are continuous brow ridges, there is no mental protuberance, the brain volume is about 700 cm3
2) the arms are longer than the legs, the big toe is opposite 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 brow ridges, the chin protuberance is poorly developed, the brain volume is about 1100 cm3
6) thoracic and sacral spine
7) the legs are longer than the arms, the big toe is opposed to the rest, the foot is arched
8) spine
Answer
Establish the chronological sequence of the stages of anthropogenesis. Write down the corresponding sequence of numbers.
1) Australopithecus
2) a skilled person
3) homo erectus
4) Neanderthal
5) Cro-Magnon
Answer
Choose one, the most correct option. What human feature was formed under the influence of biological factors of anthropogenesis?
1) making tools
2) joint work
3) the appearance of a diaphragm
4) arched foot
Answer
Establish a correspondence between the characteristics and representatives of the class Mammals, for which these characteristics are characteristic: 1) common chimpanzee, 2) homo sapiens. Write numbers 1 and 2 in the order corresponding to the letters.
A) predominance of the facial part of the skull over the brain
B) belt of the lower extremities in the form of a bowl
B) arched foot
D) the presence of a chin protuberance
D) developed brow ridges
E) laterally compressed chest
Answer
© D.V. Pozdnyakov, 2009-2019
“Social human rights” - Social human rights. Objectives: to help students understand their rights enshrined in the Constitution of the Russian Federation; - to awaken students’ interest in solving problems on social rights; cultivate tolerance; - responsible attitude towards the assigned work. - Name the main directions of social policy of our state.
“The main stages of human evolution” - Propliopithecus. Heredity, variability. Parapithecus. The struggle for existence, natural selection. Orangutan. Australopithecus. FIRST MODERN (Cro-Magnon, modern man). Generalization about the stages of anthropogenesis. Dryopithecus. Humans and apes are two different branches of the family tree.
“Human Evolution” - Heraclitus - organisms develop according to the laws of nature. Factors of anthropogenesis. Gibbon. Cro-Magnon. Gorilla. 1. Heredity 2. Variation 3. Isolation 4. Struggle for existence 5. Natural selection. Biochemical - the similarity of the chemical composition of the intracellular environment of humans and animals. Lesson objectives: Learn to find the necessary information on a topic.
“Human evolution, biology” - Tasks: a) Determine which predecessors of man switched to a terrestrial lifestyle and upright walking? Stages of human evolution." Fragment of a lesson on the topic: “The driving forces of anthropogenesis. What changes in the skull are associated with the appearance of a second signaling system in humans - speech? d) Compare the tools of anthropoids and hominids.
“The concept of evolution” - The relationship between micro- and macroevolution. Global evolutionism. The nictitating membrane is a human “rudiment”. Evolution implies universal gradual development, orderly and consistent. Selection practice. The concept of "evolution". Lamarck's views on the adaptive nature of the evolutionary process were advanced for his time.
“Man and Evolution” - Anaximander of Miletus (610-547 BC) Aristotle, Democritus, Empedocles. Ramapithecus. The thumb is opposed to the rest of the fingers of the hand. C.N.S apparatus. Chimpanzee. Pongids. Anthropology. UNSPECIALIZED INSECTIVOROUS MAMMALS. Carl Linnaeus – 18th century. Prosimians Pliopithecus Gibbons. Axial skeleton - Tubular structure Respiratory - notochord.
Tasks.
"2. Card on the board"
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"3. Cards"
| Time of existence on Earth, brain volume, use of tools and fire: Australopithecus, Homo habilis, Archanthropus, Paleoanthropus. | Write down your last name, first name, class, question. You have 10 minutes to provide a brief but as complete answer as possible. Characteristics of the structure and lifestyle of modern people. |
| Write down your last name, first name, class, question. You have 10 minutes to provide a brief but as complete answer as possible. Characteristics of the structure and lifestyle of ancient people. | Write down your last name, first name, class, question. You have 10 minutes to provide a brief but as complete answer as possible. Origin of people and modern settlement. |
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"4. Codogram. Human Races"
Topic: Factors of human evolution. Races
1. Factors of evolution
Biological factors: hereditary variability, natural selection, isolation, genetic drift, population waves - shaped the modern type of man.
For 40,000 years, the physical appearance of a person does not change, but factors continue to operate, although the role of selection has decreased.
Social factors: social lifestyle, tool activity, speech and thinking come first.
2. Human races
E 
E 
Asian-American (Mongoloid) – coarse straight hair, flattened face, very prominent cheekbones, epicanthus (?)
Three large races, at least 25 small races, many racial groups - the result of hereditary variability, natural selection, isolation, and genetic drift. Lead to morphological adaptations!
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"Factors of Human Evolution"
Lesson. Factors of human evolution
Tasks. To develop knowledge about the biological and social factors of human evolution. To characterize human races, the formation of morphological characteristics of human races as a result of adaptation to various living conditions.
Test students' knowledge and repeat the material on the topic "The First People", report the test at the next lesson.
1. Factors of evolution
The biological factors of evolution - hereditary variation, natural selection, population waves, isolation and genetic drift - led, as a result of life in trees, to the emergence of primates with their binocular color vision and long fingers. The adaptation of some primates to life in open spaces led to movement on two legs; natural selection fixed mutations useful for the new conditions. Those who were most adapted to walking upright survived; their freed hands were used to collect and carry food and objects. The larger ones survived - it is easier for them to defend themselves from predators and they dominate the group. Among the Australopithecines, those who learned to make tools began to survive; selection fixed the enlargement of the brain and changed the hand.
With the advent of modern man, biological factors of evolution lose their leading importance. The leading role of natural selection decreases, life in society ensures education and the transfer of accumulated experience, protection from animals and bad weather, and a supply of food. Over the past 40,000 years, the physical appearance of humans has remained virtually unchanged. But biological factors continue to operate in the modern world. The mutation process continues to operate, and most mutations are harmful and accumulate in a recessive state, combinative variability spreads them and creates various combinations of gene alleles, unique in each organism. The role of isolation is decreasing, but it is precisely this that preserves human races.
Social factors come first - social way of life, weapon activity, speech. As a result of social life, a complex abstract is formed thinking. If previously it was predominantly the strongest who survived, then among neoanthropes an important factor in evolution becomes altruism, caring for one's neighbor. Advantages were given to those tribes that retained people of the older generation, who retained the experience of making tools, hunting and education.
T 
2. Human races. The failure of racism
The dispersal of neoanthropic populations to Europe, Asia and Australia, along the Beringian Land Bridge to the American continent, and their further isolation led to morphological adaptations and adaptations to various climatic conditions. Large and small human races have formed - systematic divisions within the species Homo sapiens, to which the entire population of the Earth belongs.
There are three large races: Eurasian - Caucasian, equatorial - Aussie-Negroid, and Asian-American - Mongoloid. Within each race, small races and racial groups are distinguished. All races belong to the same species, as evidenced by the fertility of interracial marriages. In addition, all races are equal in biological and psychological respects.
For the Negroid race, the character is dark skin, curly hair, wide and flat nose. Dark skin of the Negroid race due to melanin pigment protects the body from excess ultraviolet rays and excess formation of vitaminD. Anti-rachitic vitamin D is formed in the skin under the influence of ultraviolet rays and is necessary to maintain calcium balance in the body. If there is too much vitamin D, calcium in the bones more than normal, they become fragile. Europeans living in latitudes with less solar radiation have lighter skin, less melanin, and accordingly produce a sufficient amount of vitamin D.
The Mongoloid race is characterized by skin with a yellowish tint, a flat face with wide cheekbones, straight black hair, eye shape and a developed epicanthus - a swollen upper eyelid. These features are adaptations to life in certain lighting conditions in open spaces.
In every race there are people who consider their race to be special, superior. Racists adhere polycentrism hypotheses, believe that races have different origins that there are “higher” and “lower” races. Some races allegedly originated from Cro-Magnons, some from Neanderthals, and some from Pithecanthropus. They explain the economic and cultural backwardness of some peoples by racial inequality, and not by socio-economic factors. But there is no scientific evidence to support racial inequality. The morphological features of races are the result of adaptations to specific living conditions.
Questions for testing on the chapter “Human Origins”
Which metaphysical scientist placed man along with prosimians and apes in the group of primates? Who suggested, who proved that man descended from hominids?
Give five characteristics of mammals that are characteristic of humans.
By what characteristics are humans classified as primates?
Give three examples of embryological evidence for the animal origin of humans.
Definition of atavisms and three examples of atavisms in humans.
Definition of rudiments and three examples of rudiments in humans.
When and from whom did primates originate?
Which monkeys are classified as pongids (great apes)?
Which monkey has 97.5% DNA similar to human DNA and the same amino acid sequence in hemoglobin?
What brain volume is typical for pongids? How many chromosomes do pongids have?
List the anthropomorphoses that appeared in anthropogenesis as a result of upright walking.
What are the consequences of the herd lifestyle of human predecessors?
What biological factors of evolution led to the emergence of humans from apes?
What social factors led to the emergence of man?
From which monkeys did Dryopithecus descend?
Who is the closest ancestor of pongids and hominids?
Who is the closest ancestor of Australopithecines?
Who is the closest ancestor of the archanthropes?
What is the historical age of the V brain of Australopithecus?
What is the historical age of the V brain of Homo habilis?
What is the historical age of the V brain of Homo erectus?
What is the historical age of the V brain of paleoanthropes?
What is the historical age of the V brain of neoanthropes?
Who belongs to the archanthropes?
Who is a paleoanthropist?
Who belongs to the neoanthropes?
Who are hominids?
What morphological features does the Caucasian race have?
What morphological features does the Negroid-Australoid race have?
What morphological features does the Mongoloid race have?
Homework assignment. Prepare for the test. Topics for abstracts and presentations: “Bigfoot, hypotheses and facts”, “Fight for fire”, “Human races”, “Man of the future”, “The bones tell the story”, “Homeland of humanity” and others.
Human development: upright posture, increase in brain volume and complication of its organization, development of the hand, lengthening the period of growth and development.
A developed hand and a tool have advantages over animals.
Making fire individual behavior speech factor accelerated development increased brain volume.
Speech is a society, division of responsibilities between its members.
Factors of human anthropogenesis: biological and social.
Biological factors– hereditary variability, the struggle for existence, natural selection, as well as the mutation process. Morphological changes of the ape-like ancestor - anthropomorphoses.
Social factors (leading role)- work activity, social lifestyle, development of speech and thinking.
The formation of humans as a biological species passed through four main stages of evolution within the hominid family:
1. Predecessors of humans (australopithecus, Homo habilis);
2. The most ancient man (archanthropes);
3. Ancient man (paleanthropes);
4. Man of the modern type (neoanthropes).
At present, there is still no paleontological data to construct all the intermediate stages in the development of hominids that led to modern humans.
The entire Cenozoic era is characterized by the gradual development of primates. The descendants of the first forms of primates of the Tertiary period now constitute a suborder of the lower primates or prosimians. About 30 million years ago, a branch separated from prosimians, which later led to the formation of ancient apes. They were small animals that lived in trees and ate plants and insects. From them descended all modern anthropoids and the subsequently extinct group of arboreal monkeys - Dryopithecus.
Dryopithecus lived approximately 25 million years ago in southern Asia and Europe, in Africa. An analysis of the finds shows that Dryopithecus had similarities with both apes and humans.
In addition to Dryopithecus, there were also Ramapithecus, which were rather small creatures that moved on four limbs. The height reached 100 - 110 cm, and the weight of an adult did not exceed 18 - 22 kg. The brain volume was 350 - 380 cm. Ramapithecines were inhabitants of open spaces. They may have used primitive tools (sticks, stones), but they were not processed.
Human Precursor Stage. Australopithecines are the most ancient, transitional forms of higher animals from monkeys to humans, found in South Africa and extinct about 1 million years ago. The common ancestor of all australopithecus is Australopithecus ramidus, which was followed by Apharensis. This Australopithecus gave different directions of evolution: 1) Australopithecus - African, Ethiopian, Robustus and 2) Homo homo, erectus. Australopithecines were relatively large organisms (weight approximately 20 -65 kg, height 100 - 150 cm). Their evolution continued for a very long time > 3 million years. They walked on short legs with their bodies straightened. The brain mass reached 450 g in some species, which is more than that of modern apes. Australopithecines lived in open spaces, where they hunted and collected plant food. In their activities they used large pebbles, as well as long bones of large ungulates; the lower jaws and shoulder blades of the same animals were used for cutting and chopping. Australopithecines were omnivores. There are finds indicating their use of fire. In a number of ways, Australopithecines were closer to humans than modern apes.
Archanthrope stage(ancient people). Their ancestors were various branches of the species Homo habilis. The most ancient people are united into one species - Homo erectus. Quite a significant number of forms of ancient people have been studied. The most famous are: Pithecanthropus (Java), Sinanthropus (China), Heidelberg man (Northern Europe), Atlantropus (Algeria), etc. Outwardly they were similar to modern people, although they had significant differences: powerful development of the brow ridge, the absence of a real chin protrusion, low forehead and flat nose. The volume of the brain was approximately 1000 cm. The average height of an adult archanthropus was almost 160 cm, but forms are known that significantly exceed these dimensions.
Apxanthropes widely used tools in their activities, such as axes and pointed points. They successfully hunted large mammals and birds. They lived mainly in caves and were able to build primitive shelters from large stones. A fire was usually maintained at permanent camp sites. Cannibalism existed within populations - eating their own kind. Joint work activity and a herd lifestyle led to further development of the brain, the size of which gave scientists reason to assume that these people must have had real, albeit very primitive speech.
After a period of maximum prosperity 600 - 400 thousand years ago, these people quickly died out, giving rise to a new branch - the Neanderthals (ancient people).
Paleoanthropus stage(ancient people). There are several groups of ancient people. Neanderthals have been well studied. The name of this species Neanderthal Man (Homosapiensncandertales) is associated with the Neanderthal Valley in Germany, where the remains of these people were first found (19th century). Neanderthals lived 20,035 thousand years ago. The era of the Great Glaciation coincided with the era of the Neanderthals. From the beginning of its emergence, this species gave rise to two branches of evolution: one was represented by large, physically developed people, but in terms of brain structure they were closer to ancient people; they were a dead-end branch of evolution. People of the other branch were smaller and less physically developed, but in terms of brain structure and morphological characteristics they were closer to modern humans. They are characterized by: a low sloping forehead, a low occiput, a continuous supraorbital ridge, a large face with widely spaced eyes, usually weak development of the chin protuberance, and large teeth. Their height reached 160 cm, their muscles were unusually well developed. The large head seems to be pulled into the shoulders.
They lived in large herds, they had a division of labor between men (making tools, hunting, making fire, protection) and women (gathering wild fruits and roots), speech was still primitive, but logical thinking was already developed. They built simple dwellings, protected themselves from the cold with clothes made from animal skins, and made more advanced flint and bone tools.
Neanderthals buried their dead or deceased fellow tribesmen. Neanderthals suddenly disappeared 40 - 35 thousand years ago. They are believed to have been partially exterminated by modern humans.
Neoanthropus stage. This name refers to both fossil forms of humans of the modern physical type and living people. Cro-Magnons are the first modern people belonging to the species Homo sapiens. The first find was made in the south of France near the town of Cro-Magnon. The appearance of Cro-Magnons dates back to 40 -30 thousand years BC. e. These people had the appearance of modern people, characterized by the absence of brow ridges, the presence of a chin, and a straight forehead. Their height was about 180 cm. The Cro-Magnons had a good command of speech, and they developed fine arts. The most important contribution of these people to the history of mankind was their habituation of a number of animals and the development of agriculture, breeding cultivated plants.
Paleontological finds indicate that during the period of the emergence of modern humans, the last Neanderthals also lived out their lives. In particular, skeletal remains of hybrids between Neanderthals and modern humans were found in Palestine.
Starting with the Cro-Magnons, biological evolution increasingly turns into social (social) evolution. As a result of the progressive development of Cro-Magnon man, modern man with characteristic racial characteristics appeared.
The doctrine of evolution is the theoretical basis of biology. It studies the causes and mechanisms of the historical development of all living organisms. Human evolution has its own characteristics and factors.
What is anthropology
According to evolutionary theory, man was formed over a long period of time. The processes of its historical development are studied by the science of anthropology.
The emergence of man has its own characteristic features. They lie in the fact that the process of formation is influenced by both social and biological factors. The first group includes the ability to work, speech. The biological factor in human evolution is, in particular, the struggle for existence. As well as natural selection and hereditary variability.
Basic provisions of evolutionary theory
According to Charles Darwin's theory, environmental conditions can cause changes in the structure of living organisms. If they are not inherited, then their role in the process of evolution is insignificant. In some individuals, changes occur in the germ cells. In this case, the trait is inherited. If it proves useful under certain conditions, then the organisms have a better chance of survival. They adapt successfully and produce fertile offspring.
Struggle for existence
The main biological factor in human evolution is its essence in the emergence of competition between organisms. The reason for its appearance is the discrepancy between the ability of different species to feed and reproduce. As a result, the species that was able to best adapt to specific conditions survives.
Despite the fact that the process of the emergence of modern man was subject to general laws, there are a number of differences. Natural selection occurred not only for strength, agility and endurance. In addition to these physical characteristics, the level of mental development also played a special role. Individuals who learned to make and use the most primitive tools, communicate with fellow tribe members, and act together had a greater chance of survival.
Natural selection
During the struggle for existence, natural selection occurs - a biological process during which adapted individuals survive and actively reproduce. Those who fail to adapt die.
Thus, natural selection is also a biological factor in human evolution. Its peculiarity was that individuals with pronounced social traits survived. The most viable people turned out to be those who invented new tools, acquired new skills and socialized. Over time, the importance of natural selection in the process of anthropogenesis decreased. This is due to the fact that ancient people gradually learned to build, improve and heat homes, make clothes, grow plants, and domesticate animals. As a result, the importance of natural selection gradually decreased.
Hereditary variability
Hereditary variability is also a biological factor in human evolution. This property of living organisms lies in the ability to acquire new characteristics in the process of their development and pass them on by inheritance. Naturally, only useful traits had evolutionary significance in the process of anthropogenesis.
Humans are similar to mammals by a number of similar biological traits. This is the presence of mammary and sweat glands, hair, and viviparity. The body cavity is divided by a muscular septum, the diaphragm, into thoracic and abdominal parts. Similar signs are the absence of nuclei in red blood cells, erythrocytes, the presence of alveoli in the lungs, the general plan of the structure of the skeleton, differentiated teeth. Both humans and animals have rudimentary (underdeveloped) organs. These include the appendix, the third eyelid, the rudiments of the second row of teeth and others. Scientists know cases of people being born with the characteristic features of animals - a developed tail, continuous hair, an additional number of nipples. This provides additional evidence from animals. But in the process of anthropogenesis, only the most useful features were preserved.
The following biological traits are specific only to humans:
Upright walking;
Enlargement of the brain and reduction of the facial part of the skull;
Arched foot with strongly developed big toe;
Movable hand, thumb opposed to the rest;
Increase in brain volume, development of its cortex.
Human biological evolution is closely related to social evolution. For example, the ability to make fire and cook food led to a decrease in the size of teeth and the length of the intestines.
Biological factors of human evolution are a necessary condition for the formation of social ones, which together led to the appearance of Homo sapiens on Earth.