Remember:

What does taxonomy study?

Answer. Systematics studies the distribution of living organisms into certain groups (taxa) according to the commonality of their structure with maximum preservation of evolutionary connections.

Why was Carl Linnaeus' system artificial?

Answer. Linnaeus was the first to create a convenient, accurate and strict plant system, albeit on an artificial basis. It is artificial because when determining the similarity of plants and classifying them, he did not take into account all the features of similarity and difference, not the totality of all morphological characteristics of a plant - a totality that alone can determine the true relationship of two forms, but built his entire system solely on the basis of one only an organ - a flower.

Questions after § 27

What is the difference between a natural system and an artificial one?

Answer. There are two types of classification - artificial and natural. In artificial classification, one or more easily distinguishable features are taken as a basis. It is created and used to solve practical problems, when the main thing is ease of use and simplicity. Linnaeus's classification is also artificial because it did not take into account important natural relationships

Natural classification is an attempt to use the natural relationships between organisms. In this case, more data is taken into account than in artificial classification, and not only external, but also internal characteristics are taken into account. Similarities in embryogenesis, morphology, anatomy, physiology, biochemistry, cellular structure and behavior are taken into account.

What is the system of living organisms proposed by K. Linnaeus? Why?

Answer. The system proposed by K. Linnaeus was artificial. Linnaeus based it not on the relationship of plants, but on several external, easily distinguishable characteristics. He based the classification of plants only on the structure of the generative organs. When classified according to 1-2 arbitrarily chosen characteristics, systematically distant plants sometimes ended up in the same class, and related ones - in different ones. For example, when counting the number of stamens in carrots and flax, Linnaeus placed them in the same group on the basis that they each had five stamens per flower. In fact, these plants belong to different genera and families: carrots are from the Apiaceae family, flax is from the flax family. The artificiality of the classification “by stamens” is in many cases so obvious that it cannot be ignored. Linnaeus’s family of “eight-stamens” included buckwheat, maple and raven’s eye.

In the 5th grade (5 stamens) there were carrots, flax, quinoa, bellflower, forget-me-not, currant, viburnum. In the 21st class, next to duckweed there were sedge, birch, oak, nettle and even spruce and pine. Lingonberries, bearberry, which is similar to it, and blueberries are cousins, but they fall into different classes, since the number of stamens is different.

But with all its shortcomings, the Linnaean plant system made it easy to understand the huge number of species already known to science.

Based on the similarity and shape of the beak, the chicken and the ostrich fell into the same order, while chickens belong to the keel-breasted species, and ostriches belong to the ratite species (and in its type “worms” 11 modern types are collected). His zoological system was built on the principle of “degradation” - from complex to simple.

K. Linnaeus, recognizing the artificiality of his system, wrote that “the artificial system will exist before the creation of the natural one.”

What is binary nomenclature and what is its significance for taxonomy?

Answer. Binary nomenclature is the designation of species of animals, plants and microorganisms in two Latin words: the first is the name of the genus, the second is the specific epithet (for example, Lepus europaeus - brown hare, Centaurea cyanus - blue cornflower). When a species is described for the first time, the author's surname is also given in Latin. Proposed by K. Baugin (1620), formed the basis of taxonomy by K. Linnaeus (1753).

The name of the genus is always written with a capital letter, the name of the species is always written with a small letter (even if it comes from a proper name).

Explain the principle of taxon hierarchy using specific examples.

Answer. At the first stage of classification, experts divide organisms into separate groups, which are characterized by a certain set of characteristics, and then arrange them in the correct sequence. Each of these groups in taxonomy is called a taxon. A taxon is the main object of systematics research, representing a group of zoological objects that actually exist in nature, which are quite isolated. Examples of taxa include such groups as “vertebrates”, “mammals”, “artiodactyls”, “red deer” and others.

In the classification of Carl Linnaeus, taxa were arranged in the following hierarchical structure:

Kingdom - animals

Class - mammals

Order - primates

Rod - person

View - Homo sapiens

One of the principles of systematics is the principle of hierarchy, or subordination. It is implemented as follows: closely related species are united into genera, genera are united into families, families into orders, orders into classes, classes into types, and types into a kingdom. The higher the rank of a taxonomic category, the fewer taxa at that level. For example, if there is only one kingdom, then there are already more than 20 types. The principle of hierarchy allows one to very accurately determine the position of a zoological object in the system of living organisms. An example is the systematic position of the white hare:

Animal Kingdom

Type Chordata

Class Mammals

Order Lagomorpha

Family Zaitsevye

Genus Hares

Mountain hare species

In addition to the main taxonomic categories, zoological taxonomy also uses additional taxonomic categories, which are formed by adding the corresponding prefixes to the main taxonomic categories (super-, sub-, infra- and others).

The systematic position of the mountain hare using additional taxonomic categories will be as follows:

Animal Kingdom

Subkingdom True multicellular organisms

Type Chordata

Subphylum Vertebrates

Superclass Quadrupeds

Class Mammals

Subclass Viviparous

Infraclass Placental

Order Lagomorpha

Family Zaitsevye

Genus Hares

Mountain hare species

Knowing the position of an animal in the system, one can characterize its external and internal structure and biological features. Thus, from the above systematic position of the white hare, one can obtain the following information about this species: it has a four-chambered heart, a diaphragm and fur (characters of the class Mammals); in the upper jaw there are two pairs of incisors, there are no sweat glands in the skin of the body (characters of the order Lagomorpha), the ears are long, the hind limbs are longer than the front ones (characters of the family Lagomorpha), etc. This is an example of one of the main functions of classification - prognostic (forecast, prediction function). In addition, the classification performs a heuristic (cognitive) function - it provides material for reconstructing the evolutionary paths of animals and an explanatory one - it demonstrates the results of studying animal taxa. To unify the work of taxonomists, there are rules that regulate the process of describing new animal taxa and assigning scientific names to them.

Classifications are usually divided into natural And artificial.

Natural classification is the classification of objects according to important, essential characteristics for them.

Artificial classification is the classification of objects according to their secondary, insignificant characteristics.

Examples of artificial classifications include the classification of books in a library by alphabet, the classification of lawyers by height, etc.

Classifications are widely used in science, and it is natural that the most complex and advanced of them are found here.

A brilliant example of scientific classification is the periodic system of elements by D.I. Mendeleev. It records the regular relationships between chemical elements and establishes the place of each of them in a single table. Summing up the results of the previous development of the chemistry of elements, this system marked the beginning of a new period in their study. It made it possible to make fully confirmed predictions regarding still unknown elements.

The classification of plants by the Swedish biologist K. Linnaeus is widely known, who arranged objects of observation - elements of living and inanimate nature - in strict order, based on their clear and specific characteristics. This classification would have to reveal the basic principles that determine the structure of the world and provide a complete and deep explanation of nature.

Linnaeus's leading idea was the opposition between natural and artificial classifications. If artificial classification uses their non-essential features to order objects, up to and including reference to the initial letters of the names of these objects, then natural classification is based on essential features, from which many derived properties of the objects being ordered follow. Artificial classification provides very meager and shallow knowledge about its objects; natural classification brings them into a system containing the most important information about them.

As Linnaeus and his followers believed, comprehensive natural classifications are the highest goal of studying nature and the crown of its scientific knowledge.

Modern ideas about the role of classifications have changed markedly. The opposition between natural and artificial classifications has largely lost its sharpness. It is not always possible to clearly separate the essential from the non-essential, especially in living nature. Objects studied by science are, as a rule, complex systems of mutually intertwined and interdependent properties. It is most often possible to single out the most significant ones from among them, leaving all the rest aside, only in the abstract. Moreover, what appears significant in one respect usually turns out to be much less important when considered in another. In addition, the process of comprehending the essence of even a simple object is endless.

Thus, the role of classification, including natural classification, in the knowledge of nature should not be overestimated. Moreover, one should not exaggerate its importance in the field of complex and dynamic social objects. The hope for a comprehensive and fundamentally complete classification is a clear utopia, even if we are talking only about inanimate nature. Living beings, very complex and in the process of constant change, are extremely difficult to fit even into the rubrics of the proposed limited classifications and do not take into account the boundaries established by man.

Understanding a certain artificiality of the most natural classifications and noting even elements of arbitrariness in them, one should not, however, go to the other extreme and belittle their importance.

Difficulties with classification most often have an objective reason. The point is not the lack of insight of the human mind, but the complexity of the world around us, the absence of rigid boundaries and clearly defined classes in it. The general variability of things, their “fluidity” further complicates and blurs this picture. Therefore, it is not always possible to clearly classify everything. Anyone who constantly aims to draw clear demarcation lines risks finding himself in an artificial world of his own creation, which has little in common with the dynamic, full of shades and transitions of the real world.

The most difficult object to classify is, without a doubt, a person. Types of people, their temperaments, actions, feelings, aspirations, actions, etc. – these are such subtle and fluid “matters” that successful attempts to typologize them are very rare.

It is very difficult to classify people taken into account the unity of their inherent properties. Even individual aspects of a person’s mental life and his activities are difficult to classify.

It can be noted that there is no generally accepted natural classification within the framework of which legal norms would be a special case of norms; there is no clear classification of human mental states in which the important distinction for criminal law between states of physiological and pathological affect has found its place and justification, etc.

In this regard, it must be emphasized that one should not be overly picky about the classifications of what, by its very nature, resists strict distinctions.

Each person is unique and at the same time has traits in common with other people. To distinguish one person from another, we use concepts such as temperament, character, personality. In everyday communication, they have a fairly definite meaning and help us understand ourselves and others. However, there are no strict definitions of these concepts, and, accordingly, there is no clear division of people by temperament and character.

The ancient Greeks divided people into choleric, melancholic, sanguine and phlegmatic. Already in our time I.P. Pavlov improved this classification and extended it to all higher mammals. In Pavlov, the choleric person corresponds to a strong excitable unbalanced type, and the melancholic person corresponds to a weak one; a sanguine person is a strong, balanced type, and a phlegmatic person is a strong, balanced, inert type. A strong, unbalanced type is prone to rage, a weak type is prone to fear, a sanguine person is typically characterized by a predominance of positive emotions, and a phlegmatic person generally does not show any violent emotional reactions to the environment. “The excitable type in its highest manifestation,” wrote Pavlov, “is mostly people of an aggressive nature; the extreme inhibited type is what is called a cowardly animal.”

Pavlov himself did not overestimate the importance of this classification of temperaments and the possibility of applying it to specific people. He spoke, in particular, not only about the four indicated types of temperament, but also about “specially human types of artists and thinkers”: in the former, a figurative-concrete signaling system predominates, in the latter, an abstract-generalized speech system predominates. None in its pure form from types of temperament are, perhaps, impossible to detect in anyone.

ARTIFICIAL CLASSIFICATION

ARTIFICIAL CLASSIFICATION

classification, in which the arrangement of concepts in the classification. schema occurs on the basis of the similarity or difference between objects and concepts in insignificant, although their own, characteristics. I.K. often plays the role of an initial stage in relation to natural classification and does not replace it until it is possible to discover creatures. object connections. An example of I. to. is botanical. Linnea, based on such characteristics as the way the stamens are connected in a plant flower. The term "I.K." often used along with the term “auxiliary”, denoting such a construction of classification. schemes, in which concepts are arranged according to their purely external, but easily observable characteristics. This makes it easier to search for concepts in the diagram and discover matches. items. The most common auxiliary. classifications based on the alphabetical arrangement of concept names: alphabetical catalogs in libraries, arrangement of surnames in various lists, etc. See Classification (in formal logic) and lit. with this article.

B. Yakushin. Moscow.

Philosophical Encyclopedia. In 5 volumes - M.: Soviet Encyclopedia. Edited by F. V. Konstantinov. 1960-1970 .

See what “ARTIFICIAL CLASSIFICATION” is in other dictionaries:

Multi-stage, branched division of the logical scope of a concept. The result of a concept is a system of subordinate concepts: the divisible concept is a genus, new concepts are species, types of species (subspecies), etc. The most complex and perfect K.... ... Philosophical Encyclopedia

logical classification- LOGICAL CLASSIFICATION (from the Latin classis rank, class and facio I do, lay out) a special kind of division (taxonomic or mereological) or a system of divisions. Taxonomic division is the separation within the scope of the concept of subclasses...

See classification. (Source: “Microbiology: a dictionary of terms”, Firsov N.N., M: Drofa, 2006) ... Dictionary of microbiology

classification- CLASSIFICATION (from the Latin classis rank and facere do) is a system of knowledge, the concepts of which mean ordered groups into which objects of a certain subject area are distributed based on their similarity in certain properties. TO.… … Encyclopedia of Epistemology and Philosophy of Science

A breakdown of many organisms based on their characteristics into a certain system of hierarchically subordinate groups - taxa (classes, families, genera, species, etc.). There are natural and artificial classifications. Natural, or... Dictionary of microbiology

This term has other meanings, see Neural network (meanings). Scheme of a simple neural network. Green indicates input neurons, blue hidden neurons, yellow output neuron... Wikipedia

The request for "Neural Network" is redirected here. See also other meanings. Scheme of a simple neural network. Green indicates input elements, yellow output element Artificial neural networks (ANN) mathematical models, as well as their software or... ... Wikipedia

Multi-stage, branched division of the logical scope of a concept. The result of K. is a system of subordinate concepts: the divisible concept is a genus, new concepts are species, types of species (subspecies), etc. The most complex and perfect K.... ... Dictionary of Logic Terms

Classification of organisms according to arbitrarily selected characteristics, which has purely practical significance. Geological Dictionary: in 2 volumes. M.: Nedra. Edited by K. N. Paffengoltz et al. 1978 ... Geological encyclopedia

Ecosystems are one of the key concepts of ecology, which is a system that includes several components: a community of animals, plants and microorganisms, a characteristic habitat, a whole system of relationships through which the interchange of substances and energies occurs.

In science, there are several classifications of ecosystems. One of them divides all known ecosystems into two large classes: natural, created by nature, and artificial, those created by man. Let's look at each of these classes in more detail.

Natural ecosystems

As noted above, natural ecosystems were formed as a result of the action of natural forces. They are characterized by:

• Close relationship between organic and inorganic substances
• A complete, closed circle of the cycle of substances: starting from the appearance of organic matter and ending with its decay and decomposition into inorganic components.
• Resilience and self-healing ability.

All natural ecosystems are defined by the following characteristics:

• 1. Species structure: the number of each species of animal or plant is regulated by natural conditions.
  2. Spatial structure: all organisms are arranged in a strict horizontal or vertical hierarchy. For example, in a forest ecosystem, tiers are clearly distinguished; in an aquatic ecosystem, the distribution of organisms depends on the depth of the water.
  3. Biotic and abiotic substances. The organisms that make up the ecosystem are divided into inorganic (abiotic: light, air, soil, wind, humidity, pressure) and organic (biotic - animals, plants).
  4. In turn, the biotic component is divided into producers, consumers and destroyers. Producers include plants and bacteria, which use sunlight and energy to create organic matter from inorganic substances. Consumers are animals and carnivorous plants that feed on this organic matter. Destroyers (fungi, bacteria, some microorganisms) are the crown of the food chain, as they carry out the reverse process: organic matter is converted into inorganic substances.

The spatial boundaries of each natural ecosystem are very arbitrary. In science, it is customary to define these boundaries by the natural contours of the relief: for example, a swamp, a lake, mountains, rivers. But in the aggregate, all ecosystems that make up the bioshell of our planet are considered open, since they interact with the environment and with space. In the most general idea, the picture looks like this: living organisms receive energy, cosmic and terrestrial substances from the environment, and the output is sedimentary rocks and gases, which ultimately escape into space.

All components of the natural ecosystem are closely interconnected. The principles of this connection develop over years, sometimes centuries. But this is precisely why they become so stable, since these connections and climatic conditions determine the species of animals and plants that live in a given area. Any imbalance in a natural ecosystem can lead to its disappearance or extinction. Such a violation could be, for example, deforestation or extermination of a population of a particular animal species. In this case, the food chain is immediately disrupted, and the ecosystem begins to “fail.”

By the way, introducing additional elements into ecosystems can also disrupt it. For example, if a person begins to breed animals in the chosen ecosystem that were not there initially. A clear confirmation of this is the breeding of rabbits in Australia. At first this was beneficial, since in such a fertile environment and excellent climatic conditions for breeding, the rabbits began to reproduce with incredible speed. But in the end everything came to a crash. Countless hordes of rabbits devastated the pastures where sheep had previously grazed. The number of sheep began to decline. And a person gets much more food from one sheep than from 10 rabbits. This incident even became a saying: “The rabbits ate Australia.” It took incredible effort from scientists and a lot of expense before they managed to get rid of the rabbit population. It was not possible to completely exterminate their population in Australia, but their numbers decreased and no longer threatened the ecosystem.

Artificial ecosystems

Artificial ecosystems are communities of animals and plants living in conditions created for them by humans. They are also called noobiogeocenoses or socioecosystems. Examples: field, pasture, city, society, spaceship, zoo, garden, artificial pond, reservoir.

The simplest example of an artificial ecosystem is an aquarium. Here the habitat is limited by the walls of the aquarium, the flow of energy, light and nutrients is carried out by man, who also regulates the temperature and composition of the water. The number of inhabitants is also initially determined.

First feature: all artificial ecosystems are heterotrophic, i.e. consuming ready-made food. Let's take a city as an example, one of the largest artificial ecosystems. The influx of artificially created energy (gas pipeline, electricity, food) plays a huge role here. At the same time, such ecosystems are characterized by a large release of toxic substances. That is, those substances that later serve for the production of organic matter in a natural ecosystem often become unsuitable in artificial ones.

Another distinctive feature of artificial ecosystems is an open metabolic cycle. Let’s take agroecosystems as an example—the most important for humans. These include fields, gardens, vegetable gardens, pastures, farms and other agricultural lands on which people create conditions for the production of consumer products. People take out part of the food chain in such ecosystems (in the form of crops), and therefore the food chain becomes destroyed.

The third difference between artificial ecosystems and natural ones is their small number of species. Indeed, a person creates an ecosystem for the sake of breeding one (less often several) species of plants or animals. For example, in a wheat field, all pests and weeds are destroyed, and only wheat is cultivated. This makes it possible to get a better harvest. But at the same time, the destruction of organisms that are “unprofitable” for humans makes the ecosystem unstable.

Comparative characteristics of natural and artificial ecosystems

It is more convenient to present a comparison of natural ecosystems and socioecosystems in the form of a table:

Natural ecosystems	Artificial ecosystems
The main component is solar energy.	Mainly receives energy from fuels and prepared foods (heterotrophic)
Forms fertile soil	Depletes the soil
All natural ecosystems absorb carbon dioxide and produce oxygen	Most artificial ecosystems consume oxygen and produce carbon dioxide
Great species diversity	Limited number of species of organisms
High stability, ability for self-regulation and self-healing	Weak sustainability, since such an ecosystem depends on human activities
Closed metabolism	Open metabolic chain
Creates habitats for wild animals and plants	Destroys wildlife habitats
Accumulates water, using it wisely and purifying it	High water consumption and pollution

There are two types of classification - artificial and natural. IN artificial classification One or more easily distinguishable features are taken as a basis. It is created and used to solve practical problems, when the main thing is ease of use and simplicity. The already mentioned classification system adopted in ancient China was also an artificial classification. Linnaeus united all worm-like organisms into one group Vermes. This group included extremely diverse animals: from simple roundworms (nematodes) and earthworms to snakes. Linnaeus's classification is also artificial because it did not take into account important natural relationships - in particular the fact that snakes, for example, have a backbone, but the earthworm does not. In fact, snakes have more in common with other vertebrates than with worms. An example of an artificial classification is their division into freshwater, marine and fish inhabiting brackish water bodies. This classification is based on the preference of these animals for certain environmental conditions. This division is convenient for studying the mechanisms of osmoregulation. Similarly, all organisms that can be seen using are called microorganisms (Section 2.2), thus uniting them into a single group that is convenient for study, but does not reflect natural relationships.

Natural classification is an attempt to exploit the natural relationships between organisms. In this case, more data is taken into account than in artificial classification, and not only external, but also internal characteristics are taken into account. Similarities in embryogenesis, morphology, anatomy, cellular structure and behavior are taken into account. Nowadays, natural and phylogenetic classifications are more often used. Phylogenetic classification based on evolutionary relationships. In this system, according to existing ideas, organisms that have a common ancestor are united into one group. The phylogeny (evolutionary history) of a particular group can be presented in the form of a family tree, such as, for example, shown in Fig. 2.3.

Rice. 2.3. The evolutionary tree of life, covering the five kingdoms according to the classification of Margelis and Schwartz (section 2.2). The length of the lines does not reflect the duration of the corresponding period.

Along with the classifications already discussed, there is also phenotypic classification. This classification is an attempt to avoid the problem of establishing evolutionary relationships, which sometimes proves very difficult and very controversial, especially in cases where the necessary fossil remains are too few or completely absent. The word "phenotypic" comes from the Greek. phainomenon, i.e. "what we see." This classification is based solely on external, i.e. visible characteristics (phenotypic similarity), and all considered characteristics are considered equally important. A wide variety of signs of an organism can be taken into account according to the principle the more, the better. And it is not at all necessary that they reflect evolutionary connections. When a certain amount of data is accumulated, the degree of similarity between different organisms is calculated on their basis; this is usually done using a computer because the calculations are extremely complex. The use of computers for these purposes is called numerical taxonomies. Phenotypic classifications often resemble phylogenetic ones, although such a goal is not pursued when creating them.