Multicellular organisms originated in the era. Multicellular organisms: signs and development. Where did multicellular organisms come from on earth?

A large international group of paleontologists have discovered in Gabon, in deposits of 2.1 billion years old, fossil remains of living creatures, centimeter-sized, resembling flatworms. Most likely, these organisms were multicellular eukaryotes. Until now, the oldest evidence for the existence of multicellular life was considered to be spiral carbon ribbons. Grypania up to 1.9 billion years old, treated as algae.

In Darwin's time, the oldest known fossil organisms were the inhabitants of the seas of the Cambrian period, which, as we now know, began 542 million years ago. The Precambrian strata were considered "dead", and Darwin saw this fact as a serious argument against his theory. He assumed that the Cambrian period must have been preceded by a long era of gradual development of life, although he could not explain why traces of this life have not yet been found. Maybe they were just looking badly?

The development of paleontology in the 20th century brilliantly confirmed Darwin's guesses. In the Precambrian sedimentary strata, many unambiguous signs of the existence of living organisms were found. The overwhelming majority of Precambrian finds are fossilized remains of microbes and various traces of their life.

The earliest evidence of life is believed to be a lightweight carbon isotopic composition from graphite inclusions in apatite crystals found in Greenland sediments aged 3.8 billion years. The oldest fossils, very similar to bacteria, and the first stromatolites - layered mineral formations that arose as a result of the vital activity of microbial communities - are 3.55–3.4 billion years old. Traces of microbial life become more numerous and diverse as the age of the rocks decreases (M. A. Fedonkin, 2006. Two chronicles of life: the experience of comparison (paleobiology and genomics on the early stages of the evolution of the biosphere)).

The question of the time of the appearance of the first eukaryotes and the first multicellular organisms remains controversial. Most modern types of animals began to develop rapidly only at the beginning of the Cambrian, but even earlier, in the Vendian or Ediacaran period (635-542 million years ago), various and numerous soft-bodied creatures appeared in the seas, including rather large ones, which are interpreted by most experts as multicellular animals (Ya. E. Malakhovskaya, A. Yu. Ivantsov. Vendian inhabitants of the earth; The secret of Doushantuo embryos is revealed, "Elements", 12.04.2007). Even earlier, in the cryogenic period (850-635 million years ago), chemical traces of the presence of primitive multicellular animals - sponges - were discovered.

Pre-Ediacaran finds of macroscopic fossils are very rare and highly controversial (some of these findings are described in the article Animals appeared over 635 million years ago, "Elements", 02/09/2009; there is also a selection of links on the topic). As a rule, the older such finds are, the more dubious they are. Until now, influenza ( Grypania). This organism has survived in the form of spiral carbonaceous ribbons, reminiscent of some kind of algae; the age of the finds is up to 1.9 billion years (MA Fedonkin. Geochemical famine and the formation of kingdoms; The size of living things increased in leaps and bounds, "Elements", 12/31/2008). However, some authors believe that influenza could be a very large and complex colony of cyanobacteria.

In the last issue of the magazine Nature a large group of paleontologists from France, Sweden, Denmark, Belgium, Canada and Germany reported on a new unique find made in the Early Proterozoic marine sediments in the southeast of Gabon. The age of the sedimentary strata containing the fossils has been determined with great precision using several independent radiometric methods. It is 2100 ± 30 million years, that is, 200 million years older than the most ancient influenza.

The authors removed from the rock more than 250 samples with fossilized remains of strange creatures of an oblong or almost round shape. Their length varies from 7 to 120 mm, width - from 5 to 70 mm, thickness - from 1 to 10 mm. The density of organisms reaches 40 pieces per square meter, and together there are specimens of different sizes and orientations.

With the help of computed X-ray tomography, the authors obtained beautiful volumetric images of ancient organisms. They clearly show a flattened wavy "border" with radial folding. The folded region usually reaches the outer edge of the body, but in some specimens the folds are visible only on the inner part of the border, and in some they are absent altogether.

In many large specimens, pyrite inclusions of two types are present in the middle part of the body: flat "sheets" and rounded granules. Analysis of the isotopic composition of sulfur in these pyrite formations showed that the "sheets" were formed soon after the death of organisms as a result of the activity of sulfate-reducing bacteria, and the concentration of sulfate in the surrounding water should have been quite high. Rounded granules were formed at the later stages of diagenesis and therefore do not carry information about the shape and structure of fossil creatures. Differences in the concentration of the stable carbon isotope 13 C in the remains of organisms and in the surrounding rock additionally confirmed that these fossils are not some kind of inorganic formations. The rock contains steranes - organic molecules derived from eukaryotic membrane sterols. This is a sure sign of the presence of eukaryotic life.

According to the authors, the found remains belong to colonial organisms, most likely colonial eukaryotes. Bacterial colonies may have similar shapes and scalloped edges, but the Gabonese finds are more complex than known bacterial colonies. According to the authors, the structure of these organisms indicates that they grew due to the coordinated division of cells that exchanged signals with each other, as occurs during the development of multicellular eukaryotes. In addition, the presence of steranes unambiguously indicates the eukaryotic nature of ancient creatures.

Chemical analysis of the rock showed that these marine sediments were formed in the presence of significant amounts of free oxygen. Therefore, it is quite possible that Gabonese organisms were aerobic (breathing oxygen), as befits normal eukaryotes. According to modern data, the first significant increase in the concentration of oxygen in the hydrosphere and atmosphere (Great oxygenation event) occurred 2.45–2.32 billion years ago, that is, approximately 200 million years before the lifetime of Gabonese organisms.

The authors refrained from attempts to more accurately determine the kinship of the newly discovered creatures. It is known that different groups of eukaryotes independently transitioned to multicellularity dozens of times, and the creatures found in Gabon may represent one of the earliest attempts of this kind.

The living world is filled with a dizzying multitude of living beings. Most organisms are made up of only one cell and are not visible to the naked eye. Many of them become visible exclusively under a microscope. Others, such as the rabbit, elephant or pine, as well as man, are made of many cells, and these multicellular organisms also inhabit our entire world in great numbers.

Building blocks of life

The structural and functional units of all living organisms are cells. They are also called the building blocks of life. All living organisms are made up of cells. These structural units were discovered by Robert Hooke back in 1665. There are about one hundred trillion cells in the human body. One is about ten micrometers in size. A cell contains cellular organelles that control its activity.

There are unicellular and multicellular organisms. The former are made up of a single cell, such as bacteria, while the latter include plants and animals. The number of cells depends on the type. Most plant cells and animal cells are between one and one hundred micrometers in size, so they are visible under a microscope.

Unicellular organisms

These tiny creatures are made up of a single cell. Amoebas and ciliates are the oldest life forms that existed about 3.8 million years ago. Bacteria, archaea, protozoa, some algae and fungi are the main groups of unicellular organisms. There are two main categories: prokaryotes and eukaryotes. They also vary in size.

The smallest are about three hundred nanometers, and some can reach sizes up to twenty centimeters. Such organisms usually have cilia and flagella that help them move around. They have a simple body with basic functions. Reproduction can be both asexual and sexual. Food is usually carried out in the process of phagocytosis, where food particles are absorbed and stored in special vacuoles that are present in the body.

Multicellular organisms

Living things that are made up of more than one cell are called multicellular. They are made up of units that identify and attach to each other to form complex multicellular organisms. Most of them are visible to the naked eye. Organisms such as plants, some animals, and algae emerge from a single cell and grow into multi-stranded organizations. Both categories of living things, prokaryotes and eukaryotes, can exhibit multicellularity.

Mechanisms of occurrence of multicellularity

There are three theories for discussing the mechanisms by which multicellularity can arise:

• The symbiotic theory states that the first cell of a multicellular organism arose from the symbiosis of different types of unicellular organisms, each of which performs different functions.
• The syncytial theory states that a multicellular organism could not have evolved from single-celled creatures with multiple nuclei. Protozoa such as ciliates and mucous fungi have multiple nuclei, thus supporting this theory.
• Colonial theory states that the symbiosis of many organisms of the same species leads to the evolution of a multicellular organism. It was proposed by Haeckel in 1874. Most multicellular formations occur due to the fact that cells cannot separate after the division process. Examples supporting this theory are volvox and eudorina algae.

Benefits of multicellularity

Which organisms - multicellular or unicellular - have the most benefits? It is rather difficult to answer this question. The multicellularity of the organism allows it to exceed the limiting dimensions, increases the complexity of the organism, allowing the differentiation of numerous cell lines. Reproduction occurs predominantly through sexual contact. The anatomy of multicellular organisms and the processes that occur in them are quite complex due to the presence of various types of cells that control their vital activity. Take division, for example. This process must be precise and well-coordinated to prevent abnormal growth and development of a multicellular organism.

Examples of multicellular organisms

As mentioned above, multicellular organisms are of two types: prokaryotes and eukaryotes. The first includes mainly bacteria. Some cyanobacteria, such as chara or spirogyra, are also multicellular prokaryotes, sometimes also called colonial. Most eukaryotic organisms are also composed of many units. They have a well-developed body structure and they have special organs for certain functions. Most well-developed plants and animals are multicellular. Examples include virtually all gymnosperms and angiosperms. Almost all animals are multicellular eukaryotes.

Features and signs of multicellular organisms

There are many signs by which you can easily determine whether an organism is multicellular or not. Among them are the following:

• They have a rather complex body organization.
• Specialized functions are performed by various cells, tissues, organs or organ systems.
• The division of labor in the body can be at the cellular level, at the level of tissues, organs and the level of organ systems.
• These are mainly eukaryotes.
• Injury or death of some cells does not globally affect the body: the affected cells will be replaced.
• Due to its multicellularity, the body can reach large sizes.
• Compared to unicellular organisms, they have a longer life cycle.
• The main type of reproduction is sexual.
• Cell differentiation is characteristic only of multicellular organisms.

How do multicellular organisms grow?

All creatures, from small plants and insects to large elephants, giraffes and even humans, start out as single, simple cells called fertilized eggs. To grow into a large adult organism, they go through several distinct developmental stages. After fertilization of the egg, the process of multicellular development begins. Throughout the entire path, growth and multiple division of individual cells occurs. This replication ultimately creates an end product that is a complex, fully formed living being.

The division of cells creates a series of complex patterns defined by genomes that are nearly identical in all cells. This diversity results in gene expression that controls the four stages of cell and embryonic development: proliferation, specialization, interaction, and movement. The first involves the replication of many cells from one source, the second is related to the creation of cells with selected, specific characteristics, the third involves the dissemination of information between cells, and the fourth is responsible for the placement of cells throughout the body for the formation of organs, tissues, bones and others. physical characteristics of developed organisms.

A few words about classification

Among multicellular creatures, two large groups are distinguished:

• invertebrates (sponges, annelids, arthropods, molluscs and others);
• chordates (all animals that have an axial skeleton).

An important stage in the entire history of the planet was the emergence of multicellularity in the process of evolutionary development. This served as a powerful impetus for the increase in biological diversity and its further development. The main feature of a multicellular organism is a clear distribution of cellular functions, responsibilities, as well as the establishment and establishment of stable and lasting contacts between them. In other words, it is a numerous colony of cells that is able to maintain a fixed position throughout the entire life cycle of a living being.

In representatives of this sub-kingdom, the body consists of many cells that perform various functions. Due to the specialization of multicellular cells, they usually lose the ability to independently exist. The integrity of the body is ensured by intercellular interactions. Individual development, as a rule, begins with the zygote, characterized by the division of the zygote into many blastomere cells, from which an organism with differentiated cells and organs is subsequently formed.

Phylogeny of multicellular

The origin of multicellular organisms from unicellular organisms is currently considered proven. The main proof of this is the almost complete identity of the structural components of the cell of multicellular animals with the structural components of the cell of protozoa. Hypotheses of the origin of multicellular organisms are divided into two groups: a) colonial, b) polyergic hypotheses.

Colonial hypotheses

Proponents of colonial hypotheses believe that the transitional form between unicellular and multicellular animals is colonial protozoa. The hypotheses of this group are listed below and briefly characterized.

Gastrea hypothesis E. Haeckel (1874). The transitional form between unicellular and multicellular animals is a single-layered spherical colony of flagellates. Haeckel called it "blastea", since the structure of this colony resembles the structure of a blastula. In the process of evolution from the "blastea" by invagination (invagination) of the colony wall, the first multicellular ones occur - "gastrea" (similar in structure to gastrula). "Gastrea" is a swimming animal, the body of which consists of two layers of cells, has a mouth. The outer layer of flagellate cells is the ectoderm and performs a motor function, the inner layer is endoderm and performs a digestive function. From "gastrea", according to Haeckel, comes primarily coelenterates, from which the rest of the multicellular groups originate. E. Haeckel considered the presence of stages of blastula and gastrula in the early stages of ontogenesis in modern multicellular organisms as evidence of the correctness of his hypothesis.

Plakula hypothesis O. Bütschli (1884) is a modified version of Haeckel's gastrea hypothesis. Unlike E. Haeckel, this scientist takes a lamellar single-layer colony of the gonium type as a transitional form between unicellular and multicellular animals. The first multicellular is Haeckel's "gastrea", but in the process of evolution it is formed by stratification of the colony and cupped bending of the bilayer plate. The evidence for the hypothesis is not only the presence of blastula and gastrula stages in the early stages of ontogeny, but also the structure of Trichoplax, a primitive marine animal discovered in 1883.

Phagocytella hypothesis I.I. Mechnikov (1882). First, I.I. Mechnikov discovered the phenomenon of phagocytosis and considered this method of food digestion to be more primitive than cavity digestion. Second, while studying the ontogeny of primitive multicellular sponges, he found that gastrula in sponges is formed not by invagination of the blastula, but by immigration of some cells of the outer layer into the embryonic cavity. These two discoveries were the basis for this hypothesis.

For the transitional form between unicellular and multicellular animals, I.I. Mechnikov also takes "blastea" (a single-layered spherical colony of flagellates). The first multicellular organisms - "phagocytellae" originate from the "blastea". "Phagocytella" does not have a mouth, its body consists of two layers of cells, the flagellar cells of the outer layer perform the motor function, the inner one - the function of phagocytosis. "Phagocytella" is formed from the "blastea" by immigration of a part of the cells of the outer layer into the colony. The prototype, or living model of the hypothetical ancestor of multicellular organisms - "phagocytella" - I.I. Mechnikov considered the sponge larva to be a parenchymula.

Phagocytella hypothesis A.V. Ivanov (1967) is an augmented version of Mechnikov's hypothesis. Evolution of lower multicellular organisms, according to A.V. Ivanov, is as follows. The transitional form between unicellular and multicellular animals is a colony flagellate colony, which does not have a cavity. From colonies of the collar flagellar type Proterospongia by immigration of a part of the cells of the outer layer inward, "early phagocytellae" are formed. The body of "early phagocytellae" consists of two layers of cells, does not have a mouth, in structure it is average between the structure of the parenchymula and trichoplax, closer to trichoplax. From "early phagocytellae" come lamellar, sponges and "late phagocytellae". The outer layer of "early" and "late phagocytellae" is represented by flagellate cells, the inner layer is amoeboid cells. Unlike "early phagocytellae", "late phagocytellae" have a mouth. From "late phagocytellae" come coelenterates and ciliary worms.

Polyergide hypotheses

Proponents of polyergid hypotheses believe that the transitional form between unicellular and multicellular animals is polyergid (multinucleate) protozoa. According to I. Khadzhi (1963), the ancestors of multicellular organisms were multinucleated ciliates, the first multicellular organisms were flatworms of the planarian type.

The most reasoned is the hypothesis of "phagocytella" I.I. Mechnikov, revised by A.V. Ivanov.

The sub-kingdom of Multicellular is subdivided into three supersections: 1) Phagocytelloid, 2) Parazoi, 3) Eumetazoi.

MOSCOW, December 12 - RIA Novosti. The oldest multicellular organisms, discovered in the mid-20th century in the Ediacaran Hills in Australia, may not be primitive marine invertebrates, but land lichens, says an American paleontologist in an article published in the journal Nature.

The first multicellular organisms arose on Earth in the Proterozoic, a segment of geological history spanning from 2500 to 550 million years ago. To date, scientists have discovered a very small number of fossils from this period. The most famous of these are the imprints of multicellular organisms found in the rocks of the Ediacaran Hills in Australia in 1947.

Gregory Retallack from the University of Oregon in Eugene (USA) doubted that these organisms were marine invertebrates, and offered his explanation of their nature, having studied the chemical composition of the rocks in which the prints of the oldest living creatures lay.

Retallac's attention was drawn to the fact that the rocks surrounding the remains of the Ediacaran creatures were not similar in structure and mineral composition to the sedimentary deposits that formed on the bottom of the sea. The scientist decided to test his suspicions by studying the chemical composition of samples from the Ediacaran Hills and their microstructure using an electron microscope.

The chemical composition of the soil, as well as the shape and size of the mineral grains, indicate that this part of Australia was not in a tropical, but temperate or even subarctic climate. The water off the coast of the future Ediacaran Hills was supposed to freeze during the winter, which casts doubt on the possibility of the existence of primitive multicellular organisms inside it.

On the other hand, the mineral composition of the rocks surrounding the footprints is very similar to paleosols - fossilized fragments of ancient soils. In particular, the samples from the Ediacaran Hills and other fragments of paleosols have the same isotopic composition, and on the surface of the samples there are microscopic depressions similar to film colonies of bacteria or primitive roots of lichens or fungi.

Soil and similar "roots" should not have existed on the bottom of shallow bays or other parts of the primordial ocean, Retallack said. This allowed him to suggest that the found prints are not actually marine multicellular organisms, but fossilized remains of lichens that lived on the surface of the land. Some of the "multicellular animals", according to the researcher, are actually traces of ice crystals frozen into the ancient soil.

This conclusion has already met with criticism from the scientific community. In particular, paleontologist Shuhai Xiao from the Virginia Polytechnic University (USA) noted in the comments on an article in the journal Nature that microscopic depressions on the surface of Ediacaran rocks could have been left only by moving organisms, not motionless lichens. According to him, similar remains of multicellular organisms were found in other sediments of the end of the Proterozoic, whose "marine" origin is beyond doubt.

(plant and animal communities)

The brightest event in the evolution of living forms was the emergence of plants and living beings from the water and the subsequent formation of a wide variety of terrestrial plants and animals. From them in the future, highly organized forms of life.

The transition to a terrestrial habitat required corresponding changes, since body weight on land is greater than in water, and air, unlike water, does not contain nutrients. In addition, dry air, differently than water, passes light and sound through itself.

The latest evolution of eukaryotes has been associated with the division into plant and animal cells. An important stage in the development of life and its complication was the emergence of about 900 million years ago sexual reproduction. Sexual reproduction consists in the mechanism of DNA fusion of two individuals and the subsequent redistribution of genetic material, in which the offspring is similar to the parents, but not identical to them. The advantage of sexual reproduction is that it significantly increases species diversity and dramatically accelerates evolution, allowing faster and more efficient adaptation to environmental changes.

The embryo could remain inside the seed for a long time until the plant scatters the seeds, and they do not get into favorable growing conditions. And then the sprout inflates the seed coat, germinates and feeds on reserves until its roots and leaves themselves support and nourish the plant. So in all seed plants, the dependence of the process of sexual reproduction on the presence of an aquatic environment disappears.

The transition to seed reproduction is associated with a number of evolutionary advantages: The diploid embryo in the seeds is protected from unfavorable conditions by the presence of covers and is provided with food, and the seeds have adaptations for distribution by animals, etc.

In the future, there is pollination specialization(with the help of insects) and the spread of seeds and fruits by animals, strengthening the protection of the embryo from unfavorable conditions, providing food, the formation of covers, etc. In the early Cretaceous period, the seed protection system of some plants is improved by the formation of an additional shell.

The emergence of angiosperms was associated with the improvement of the fertilization process: with the transition to the fact that the pollen was carried not by the wind, but by animals (insects). This required significant transformations of the plant organism. Such an organism must contain means of signaling to animals about itself, attracting animals to itself, in order to then carry pollen to another plant of the same species, and, in the end, the animal itself must receive something for itself (nectar or pollen).

This whole complex of issues was resolved on the way of the emergence of a huge variety of beautiful and diverse angiosperms (flowering) plants: the flowers of each plant in appearance (shape, color) appearance (and smell) should differ from the flowers of other plants.

Flowering plants are characterized by high evolutionary plasticity, diversity generated by pollination by insects. Gradually spreading, flowering plants conquered all continents, won the struggle for land. The flower played the main role in this, providing the attraction of pollinating insects. In addition, flowering plants have a developed conducting system: the fruit, the embryo of flowering plants have significant food reserves, which ensures the development of the embryo and seed. In the Cenozoic, botanical and geological areas close to modern ones are formed. Angiosperms achieve dominance. Forests are the most widespread on Earth. The territory of Europe was covered with lush forests: coniferous forests prevailed in the north, chestnut-beech forests with the participation of giant sequoias in the south.

Geographic areas (landscapes) have changed with climate change. With warming, heat-loving plants spread to the north, and with a cold snap - to the south.

A significant step in the further complication of the organization of living beings was the emergence of about 700-800 million years ago multicellular organisms with a differentiated body, developed tissues, organs that performed certain functions. The first multicellular animals are represented by several types at once: sponges, intestinal cavity, brachiopods, arthropods.

Multicellular species are derived from the colonial forms of unicellular flagellates. The evolution of multicellular organisms went in the direction of improving the methods of movement and better coordination of the activity of cells, improving the methods of breathing, etc.

In the Proterozoic and at the beginning of the Paleozoic, plants inhabit mainly the seas. Among those attached to the bottom, there are green and brown algae, and in the water column there are golden, red and other algae. Almost all the main types of animals already existed in the Cambrian seas, which later only specialized and improved. The appearance of the marine fauna was determined by numerous crustaceans, sponges, corals, echinoderms, various mollusks, brachiopods, and trilobites. Numerous corals lived in warm and shallow seas; cephalopods, creatures similar to modern squids, several meters long, reached significant development. At the end of the Ordovician, large carnivores appear in the sea, reaching 10-11 m in length. In the Ordovician, about 500 million years ago, the first animals with skeletons, vertebrates, appeared. This was a significant milestone in the history of life on Earth.

The first vertebrates arose in shallow freshwater bodies, and only then these freshwater forms conquer the seas and oceans. The first vertebrates were small (about 10 cm long) creatures, jawless fish-like, covered with scales, which helped defend against large predators (octopuses, squids).

Further evolution of vertebrates went in the direction of the formation of jawed fish-like, which quickly supplanted most of the jawless. In the Devonian, lungs also appear, which were adapted to breathing in water, but had lungs. As you know, sharks are cartilaginous. Bony fish are the most numerous group of fish, currently prevailing in the seas, oceans, rivers, lakes. Some freshwater (lungfishes), apparently, gave life first to primary stegocephals, and then to terrestrial vertebrates. Thus, the first amphibians appear in the Devonian. In the Devonian, another extremely progressive group of animals appeared - insects.

Table 6.1.

Development of living organisms on the planet

Continuation of table 6.1.

The formation of insects indicated that in the course of evolution, two different ways of solving the problems of strengthening the body and improving the forms of reflection have developed. In vertebrates, the internal skeleton plays the role of a skeleton, in higher forms of invertebrates, the external one. As for the forms of reflection, insects have an extremely complex nervous system with huge and relatively independent nerve centers scattered throughout the body. In vertebrates, the development of the brain is noted and the predominance of conditioned reflexes over unconditioned ones. The difference between these two different ways of constructing the most important evolutionary problems was fully manifested before the transition to life on land. The reptiles that came out on land turned out to be a promising form. They mastered the land. Some reptiles become carnivorous, others vegetative.

In the Cretaceous period, giant herbivorous dinosaurs appear (Fig. 6.2). Marine reptiles develop especially intensively in the Jurassic (ichthyosaurs). The conquest of the air environment is also gradually taking place. Insects began to fly back in the Carboniferous, and for about 100 million years they were sovereign in the air. And only in the Triassic do the first flying lizards appear. Reptiles successfully master the air. Large insects appear. Some flying lizards had a wingspan of up to 20m. At the end of the Mesozoic, placental mammals appear.

Rice. 6.2. Diplodocus reached 30 m in length and was one of the largest animals that ever lived on Earth.

At the end of the Mesozoic, under conditions of cooling, the areas occupied by rich vegetation are reduced. This entails the extinction, first of the herbivorous dinosaurs, and then of the predatory dinosaurs that hunt them. In cold weather conditions, warm-blooded animals such as birds and mammals receive exceptional benefits. The first carnivorous mammals appear in the Paleocene. At the same time, some species of mammals “leave” for the sea (cetaceans, pinnipeds). A detachment of primates is isolated from some species of insectivores. In the Pliocene, all modern families of mammals are already found.

In the Cenozoic, those most important trends are formed that led to the emergence person. This concerns the emergence of a herd lifestyle, which was a stepping stone to the emergence of social communication. Moreover, if in insects biosociality led to the loss of individuality; then in mammals, on the contrary, to emphasize the individual traits of an individual. In the Neogene, numerous species of monkeys appear in the vast open spaces of the savannahs of Africa. Some primate species move to upright posture. The development of consciousness led to the fact that they began to plan their actions.

This is how the prerequisites for the emergence of Human and the world of culture.

Geology and geochemistry made it possible to determine the time of existence of transitional forms between humans and those animals from which humans descended. Archeology, studying material monuments of the ancient material culture of man, reveals the history of the development of human society. The most important thing that distinguishes a person from an animal is a highly developed consciousness, with the help of which a person began to plan his actions, consciously produce all the means of subsistence and articulate speech necessary for him. However, despite many common features between humans and apes, none of the living monkeys was the ancestor of humans.