Plan:

1 Examples
2 The emergence of binomial nomenclature
- 2.1 Polynomial names
- 2.2 Carl Linnaeus: the emergence of nomina trivialia
- 2.3 The first nomenclature codes

4 Literature and links

Introduction

Binomial, or binary, or binomial nomenclature- a method adopted in biological taxonomy to designate species using a two-word name ( binomen), consisting of a combination of two names or names: a genus name and a species name (according to the terminology adopted in zoological nomenclature) or a genus name and a species epithet (according to botanical terminology). Gender name Always written with capital letters, species name (specific epithet) - Always with a small one (even if it comes from a proper name). In the text, the binomen is usually written italics. The name of the species (specific epithet) should not be given separately from the name of the genus, since without the name of the genus it is completely meaningless. In some cases, it is permissible to shorten the genus name to one letter or a standard abbreviation. According to the established tradition in Russia, the phrase binomial nomenclature(from English binomial), and in botanical - binary, or binomial nomenclature(from lat. binominalis).

1. Examples

For example, in the scientific names Papilio machaon Linnaeus, 1758 (swallowtail) or Rosa canina Linnaeus, 1753 (rose hip), the first word is the name of the genus to which the species belongs, and the second word is the name of the species or specific epithet. After the binomen there is often an abbreviated reference to the work in which this type was first described in the scientific literature and given a name given according to certain rules. In our case, these are links to the works of Carl Linnaeus: tenth edition Systema naturae(1758) and Species plantarum (1753).

Examples of abbreviated names (usually the default for well-known laboratory organisms or when listing species of the same genus): E. coli(Escherichia coli T. Escherich, 1885), S. cerevisiae(baker's yeast, Saccharomyces cerevisiae Meyen ex E.C. Hansen). Some of these abbreviated names have found their way into popular culture, For example T. rex (T. rex from Tyrannosaurus rex Osborn, 1905, tyrannosaurus).

2. The emergence of binomial nomenclature

2.1. Polynomial names

Binomial nomenclature in the form in which it is used in our time developed in the second half of the 18th - early 19th centuries. Before this, rather long, verbose, or polynomial names were used.

The first polynomials were formed spontaneously during the compilation of herbal books of the 16th century. The authors of these works, the “fathers of botany” Otto Brunfels, Hieronymus Tragus and Leonhart Fuchs, comparing the plants of Germany with the plants described by ancient authors (mainly Dioscorides), formed new names by adding epithets to the names of the ancients, which were, like most popular names , are initially single-word. As the number of known plant species increased, the polynomials grew, sometimes reaching up to one and a half dozen words. So, for example, one of the mosses was called Muscus capillaceus aphyllos capitulo crasso bivalvi, that is Moss in the form of a hair, leafless, with a thickened bivalve head. This name said more about the species than its current name - Buxbaumia leafless ( Buxbaumia arylla): it contained all the main identifying characteristics of the species. But it was very difficult to use such names when compiling, say, a list of plants in a given area. In addition, polynomials gave rise to an uncontrollable desire for fragmentation existing species into small and minute new species, since the verbose “specific difference” included many variable but unimportant characters of plants and animals. The number of known species increased like an avalanche. Some of the polynomials consisted of only two words, but the similarity to binomial nomenclature was only superficial. This was due to the fact that the concept of ranks of systematic categories and the idea of a necessary connection between the procedures of classification and naming became widespread only at the end of the 17th century.

Only in the works of Joseph Pitton de Tournefort (1694) and Augustus Bachmann (Rivinus) (1690s) was a complex system of subordinate categories introduced (in particular, the categories of genus and species were isolated in a more or less modern sense) and the principle was first applied "one genus - one name." According to this principle, the names of all plants belonging to the same genus should begin with the same word or stable phrase - the name of the genus. Species names were to be formed by adding more or less verbose species differences to the genus name (the so-called differenitae specificae). Because differenita specifica had diagnostic value, there was no need for it if the genus was not divided into species. The name in such cases consisted only of the genus name without adding specific distinction.

2.2. Carl Linnaeus: emergence nomina trivialia

The transformation of nomenclature was one of the most important proposals of Carl Linnaeus. Linnaeus believed that it was necessary to make the names of genera single-word, getting rid of stable phrases like Bursa pastoris (shepherd's purse) or Dens leonis (Leontodon, kulbaba), and compiling verbose species differences (lat. differentiae specificae) - subject to strict rules. According to Linnaeus's views, nothing should be used in species differences that could not be seen on the plant itself (place of growth, the name of the botanist who first found it, comparisons with other plants). They should concern only the structure of plants, described using standardized terminology (a significant part of the work “Philosophy of Botany” is devoted to its detailed presentation). The length of the species difference should not, according to Linnaeus' calculations, exceed twelve words (six nouns for the main parts of the plant and six adjectives characterizing them). In some cases, a species difference could consist of one adjective if it characterized the entire plant as a whole.

Page 105 Systema Naturae Carl Linnaeus 1767 edition. Note the nomina trivialia (Monoceros And Mysticetus), placed to the left of the description of whale species, the absence differentia specifica in the only species of the genus Monodon(narwhal) and its presence in the first of the species of the following genus: Balaena naribus flexuosis in medio capite, dorso impinni(bowhead whale).

The use of verbose names in practice was associated with certain difficulties. Firstly, they were long, and secondly, they were subject to change: when new species were added to the genus, they had to be revised so that they could retain their diagnostic functions. In this regard, in travel reports and “economic” studies on the economic use of plants and animals, Linnaeus and his students used abbreviated names. At first, such abbreviated names consisted of the genus name and species number, according to the writings of Linnaeus Flora suecica or Fauna suecica. From the mid-1740s they began experimenting with the use of so-called trivial names (lat. nomina trivialia). They first appeared in the index to the description of the trip to Öland and Gotland (1745) and then in Pan Svecicus(a catalog of the plants of Sweden, indicating which species of livestock feed on them) (1749).

Nomen triviale usually it was one word or stable phrase, sometimes - the ancient name of the plant, rejected by Linnaeus for some reason (as in the case of Capsella bursa-pastoris, where Bursa pastoris, in fact, is a rejected two-word generic name), sometimes something completely unsuitable as a genuine differentia, such as color, smell, country of origin or similar plant(as in Quercus ilex). Invention and Application nomina trivialia was limited by only two rules: they should not be repeated within the genus and should not change after the addition of new species to the genus. Linnaeus was the first to consistently apply nomina trivialia to all types of plants in Species Plantarum(1753), and in the tenth edition Systema Naturae(1758) - to all types of animals and minerals. Unlike differentiae, nomina trivialia were given to plants and animals and in those genera that contained only one species.

In the works of Linnaeus and his closest followers nomina trivialia located in the margins of the page. The custom of placing nomen trivial directly behind the name of the genus, as is currently done, it developed only towards the end of the 18th - early XIX centuries

2.3. The first nomenclature codes

The practice of using binomen was fixed by the first nomenclature codes that appeared in the 1840-60s. The need to develop codes regulating the formation of new names and the use of old ones was associated with the growing nomenclatural chaos. With an increase in the number of authors, insufficient intensity of scientific communication and a weakening of the disciplinary influence of Linnaeus's outdated works, which did not correspond to the nomenclatural practices of that time, the number of new names began to increase like an avalanche.

The first nomenclature rules were developed in England and adopted at a meeting of the British Association for the Advancement of Science (BAAS) in 1842. Hugo Theodore Strickland, an English naturalist, geologist and ornithologist, took the most active part in their development. In botany, an attempt to codify the rules was made by Alphonse Decandolle, who published “The Laws of Botanical Nomenclature” in 1867. Later, at the beginning of the 20th century, international codes of zoological and botanical nomenclature were developed on their basis (and in the second half of the 20th century, special codes of nomenclature for bacteria and viruses). In all these codes, the scientific name of a species is considered to be a binomial name consisting of the name of the genus and what was invented by Linnaeus and his students as nomen trivial.

Notes

Shipunov A. B. Fundamentals of the theory of systematics: Tutorial. - M.: Open Lyceum VZMSH, Dialogue-MSU, 1999. - 56 p.
See Atran, S. (1990) Cognitive Foundations of Natural History: Towards an Anthropology of Science. Cambridge, England: Cambridge University Press and Kupriyanov A.V. (2005) Prehistory of biological systematics: “folk taxonomy” and the development of ideas about the method in natural history late XVI- beginning of the 18th century St. Petersburg: EUSP Publishing House.
See: Heller, J. L. (1983) Studies in Linnaean method and nomenclature. Marburger Schriften zur Medizingeschichte. Bd. 7. Frankfurt am Main: Peter Lang. and Koerner, L. (1999) Linnaeus: Nature and Nation. Harvard University Press.
See “Report of a Committee appointed “to consider of the rules by which the Nomenclature of Zoology may be established on a uniform and permanent basis.”” by H. E. Strickland, J. S. Henslow, John Philipps, W. E. Shuckard, John Richardson, G. R. Waterhouse , Richard Owen, W. Yarrell, Leonard Jenyns, C. Darwin, W. J. Broderip, J. O. Westwood. Report on the Twelfth Meeting of the British Association for the Advancement of Science; held at Manchester in June 1842. London. John Murray, Albemarle Street. 1843. P. 105-121. and Alphonse de Candolle. Lois de la nomenclature botanique. Paris. 1867

4. Literature and links

Jeffrey C. Biological nomenclature. - M.: Mir. 1980.

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's the difference natural system from artificial?

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' 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.

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 kinds and families: carrots from the Umbelliferae family, flax 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” includes buckwheat, maple and raven’s eye.

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

But for all its shortcomings Linnaean system plants made it easy to understand a huge number species already known to science.

Based on the similarity and shape of the beak, chicken and 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” there are 11 modern types). His zoological system was built on the principle of “degradation” - from complex to simple.

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

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

Answer. Binary nomenclature- designation of species of animals, plants and microorganisms by two in 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 place them in 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, additional taxonomic categories are used in zoological systematics, 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 the animal in the system, one can characterize its external and internal structure, features of biology. 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.

Terminology). Gender name Always written with a capital letter, species name (specific epithet) - Always with a small one (even if it comes from a proper name). In the text, the binomen is usually written italics. The name of the species (specific epithet) should not be given separately from the name of the genus, since without the name of the genus it is completely meaningless. In some cases, it is permissible to shorten the genus name to one letter or a standard abbreviation. According to the established tradition in Russia, the phrase binomial nomenclature(from English binomial), and in botanical - binary, or binomial nomenclature(from lat. binominalis).

Examples

For example, in the scientific names Papilio machaon Linnaeus, 1758(swallowtail) or Rosa canina Linnaeus, 1753(rose hips), the first word is the name of the genus to which these species belong, and the second word is the name of the species or specific epithet. After the binomen there is often an abbreviated reference to the work in which the species was first described in the scientific literature and provided with a name given according to certain rules. In our case, these are references to the works of Carl Linnaeus: tenth edition Systema naturae() And Species plantarum ().

Examples of abbreviated names (usually the default for well-known laboratory organisms or when listing species of the same genus): E. coli(Escherichia coli T. Escherich, 1885), S. cerevisiae(baker's yeast, Saccharomyces cerevisiae Meyen ex E.C. Hansen). Some of these shortened names have made their way into popular culture, e.g. T. rex (T. rex from Tyrannosaurus rex Osborn, 1905, tyrannosaurus).

The emergence of binomial nomenclature

Polynomial names

Binomial nomenclature in the form in which it is used in our time developed in the second half of the 18th - early 19th centuries. Before this, rather long, verbose, or polynomial names were used.

Carl Linnaeus: emergence nomina trivialia

The nomenklatura reform was one of the important aspects transformations initiated by Carl Linnaeus. Linnaeus believed that it was necessary to make the names of genera single-word, getting rid of stable phrases like Bursa pastoris (shepherd's purse) or Dens leonis (Leontodon, kulbaba), and compiling verbose species differences (lat. differentiae specificae) - subject to strict rules. According to Linnaeus's views, nothing should be used in species differences that could not be seen on the plant itself (place of growth, the name of the botanist who first found it, comparisons with other plants). They should concern only the structure of plants, described using standardized terminology (a significant part of the work “Philosophy of Botany” is devoted to its detailed presentation). The length of the species difference should not, according to Linnaeus' calculations, exceed 12 words (6 nouns for the main parts of the plant and 6 adjectives characterizing them). In some cases, a species difference could consist of one adjective if it characterized the entire plant as a whole.

The use of verbose names in practice was associated with certain difficulties. Firstly, they were long, and secondly, they were subject to change: when new species were added to the genus, they had to be revised so that they could retain their diagnostic functions. In this regard, in travel reports and “economic” studies on the economic use of plants and animals, Linnaeus and his students used abbreviated names. At first, such abbreviated names consisted of the genus name and species number, according to the writings of Linnaeus Flora suecica or Fauna suecica. From the mid-1740s. they began experimenting with the use of so-called trivial names(lat. nomina trivialia). They first appeared in the index to the description of the trip to Öland and Gotland (1745) and then in Pan Svecicus(a catalog of the plants of Sweden, indicating which species of livestock feed on them) (1749).

Nomen triviale usually it was one word or a set phrase, sometimes it was the ancient name of the plant, rejected by Linnaeus for some reason (as in the case of Capsella bursa-pastoris, where Bursa pastoris, in fact, is a rejected two-word generic name), sometimes something completely unsuitable as a genuine differentia, as color, smell, country of origin or similar plant (as in the case of Quercus ilex). Invention and Application nomina trivialia was limited by only two rules: they should not be repeated within the genus and should not change after the addition of new species to the genus. Linnaeus was the first to consistently apply nomina trivialia to all types of plants in Species Plantarum(1753), and in the tenth edition Systema Naturae(1758) - to all types of animals and minerals. Unlike differentiae, nomina trivialia were given to plants and animals and in those genera that contained only one species.

The first nomenclature codes

The first nomenclatural rules were developed in England and adopted at a meeting of the British Association for the Advancement of Science (BAAS) in the city. Hugo Theodore Strickland, an English naturalist, geologist and ornithologist, took the most active part in their development. In botany, an attempt to codify the rules was made by Alphonse Decandolle, who published “The Laws of Botanical Nomenclature” in 1867. Later, at the beginning of the 20th century, international codes of zoological and botanical nomenclature were developed on their basis (and in the second half of the 20th century, special codes of nomenclature for bacteria and viruses). In all these codes, the scientific name of a species is considered to be a binomial name consisting of the name of the genus and what was invented by Linnaeus and his students as nomen trivial.

Notes

Literature and links

Jeffrey C. Biological nomenclature. M.: Mir. 1980.
International Code of the Zoological Nomenclature (Fourth Edition, 2000)
International Code of the Botanical Nomenclature (Vienna, 2005)

Binary nomenclature- * binary nomenclature * binary nomenclature designation of species in two words: the first name of the genus (in Latin written with capital letter, in Russian, as a rule, is written with a lowercase letter), the second specific epithet (written with a lowercase letter, if not ... ... Genetics. Encyclopedic Dictionary

binary nomenclature- (binomial nomenclature), 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 hare, Centaurea cyanus blue cornflower). Proposed... ... Encyclopedic Dictionary

Binary nomenclature- (from Latin binarius double) binomial nomenclature (biological), designation of plants, animals and microorganisms with a double name according to Genus and Species. B. n. was introduced by C. Linnaeus (See Linnaeus) and was first consistently applied by him in 10... ... Great Soviet Encyclopedia

BINARY NOMENCLATURE- (from Latin binarius double and nomenclatura list), binomial nomenclature, a way of designating the species of an organism with two Latin words, the first of which means the name of the genus, the second the specific epithet. B. n. introduced... ... Veterinary encyclopedic dictionary

BINARY NOMENCLATURE- (binomial nomenclature), designation of species of food, bacteria and microorganisms in two lats. in words: first name genus, second specific epithet (for example, Lepus europaeus brown hare, Centaurea cyanus blue cornflower). Proposed by K. Baugin (1620),… … Natural science. Encyclopedic Dictionary

BINARY NOMENCLATURE- a rule introduced by K. Linnaeus for designating the scientific name of plant species, which consists in the fact that the name of each species consists of two words, the first of which designates the genus, and the first and second together constitute the name of the species. First… … Dictionary of botanical terms

Binary nomenclature (binomial nomenclature)- 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, the brown hare). Proposed by the Swiss biologist Caspar Baugin (Bohen) (1620), it formed the basis of taxonomy... ... The beginnings of modern natural science

binary nomenclature- private rule of biol. nomenclature, according to which the names of species are made up of two words - the first denotes the genus (in Latin, written with a capital letter), the second - the species (written with a lowercase letter, if it does not denote its own name). Introduced... ... Dictionary of microbiology

Carl Linnaeus

nominatrivialia

Binomial, or binary, or binomial nomenclature binomen

Lamarck and his evolutionary theory

Jean Baptiste Pierre Antoine de Monet Lamarck- French natural scientist.

Lamarck became the first biologist who tried to create a slender and holistic theory evolution of the living world, known in our time as one of the historical evolutionary concepts called Lamarckism.

Lamarck's evolutionary theory- the doctrine according to which all living organisms strive for progress, developing from simple to complex. Thus, organisms change expediently, adapting to environmental conditions. Such changes are caused by the direct influence of the environment, the exercise of organisms and the inheritance by descendants of characteristics acquired during life.

In his opinion, adapting to environmental conditions is an innate property of living organisms.

Darwin's theory of evolution

Scientific background. The evolutionary theory of Charles Darwin was outlined by him in the book “The Origin of Species by Means of Natural Selection, or the Preservation of Favored Breeds in the Struggle for Life” (published in 1859). By the middle of the 20th century, a number of important generalizations and discoveries were made that contradicted creationist views and contributed to the strengthening and further development of the idea of evolution, which created the scientific prerequisites for evolutionary theory Ch. Darwin.

Darwin's evolutionary theory is a holistic doctrine of historical development organic world. It covers a wide range of problems, the most important of which are evidence of evolution, identifying the driving forces of evolution, determining the paths and patterns of the evolutionary process, etc. Essence evolutionary doctrine consists in the following basic provisions: All types of living beings inhabiting the Earth were never created by anyone. Having arisen naturally, organic forms were slowly and gradually transformed and improved in accordance with environmental conditions.

In Darwin's evolutionary theory, the prerequisite for evolution is hereditary variability, and driving forces evolution - the struggle for existence and natural selection. When creating an evolutionary theory, Charles Darwin repeatedly turned to the results of breeding practice. He showed that the diversity of varieties and breeds is based on variability. Variability is the process of the emergence of differences in descendants compared to ancestors, which determine the diversity of individuals within a variety or breed. Darwin believes that the causes of variability are the influence of factors on organisms external environment(direct and indirect), as well as the nature of the organisms themselves (since each of them specifically reacts to the influence of the external environment).

The main result of evolution is the improvement of the adaptability of organisms to living conditions, which entails the improvement of their organization. As a result of the action of natural selection, individuals with traits useful for their prosperity are preserved. Darwin provides a lot of evidence for the increased adaptability of organisms to environmental conditions caused by natural selection. This, for example, is the widespread use of protective colors among animals, making them less noticeable in their habitats: moths have a body color that matches the surface on which they spend the day; females of open nesting birds (grouse, black grouse, hazel grouse) have a plumage color that is almost indistinguishable from the surrounding background; in the Far North, many animals are colored white(partridges, bears), etc.

The Difficulties of Darwinism

Only a very small proportion of mutations result in positive traits. Most new prizes are recessive (if received from one parent, they do not appear phenotypically).

1. The theory cannot explain the appearance of polygenic traits (encoded by several genes at once. Thus, to increase the length of a giraffe’s neck, it is necessary that the (necessary) mutation occur in many genes at once, which is extremely unlikely.

2. many traits fall under the influence of natural selection only when they are fully expressed and developed (horns in ungulates)

3. the threshold of complexity of living organisms. Living organisms cannot have fewer than 1200 genes.

Ribosomes are very complex. They are the same in all eukaryotes. Any mutation in the ribosome is lethal.

Linnaeus and binary species nomenclature

Carl Linnaeus- Swedish naturalist and doctor, creator of a unified system of classification of flora and fauna, in which the knowledge of the entire previous period of development was generalized and largely streamlined biological science, which brought him worldwide fame during his lifetime. One of Linnaeus’s main achievements was the definition of the concept of biological species, the introduction into active use of binomial (binary) nomenclature and the establishment of a clear subordination between systematic (taxonomic) categories].

Linnaeus laid the foundations of modern binomial (binary) nomenclature, introducing into the practice of taxonomy the so-called nominatrivialia, which later began to be used as species epithets in the binomial names of living organisms. The method introduced by Linnaeus of forming a scientific name for each species is still used today. Usage Latin name of two words - the name of the genus, then the specific name - made it possible to separate nomenclature from taxonomy.

Carl Linnaeus is the author of the most successful artificial classification of plants and animals, which became the basis for the scientific classification of living organisms. He shared natural world into three “kingdoms”: mineral, plant and animal, using four levels (“ranks”): classes, orders, genera and species.

Described about one and a half thousand new species of plants and large number species of animals.

Introduction to taxonomy. Binary nomenclature. Systematic units.

Systematics is a science about the diversity of plant organisms, which determines their place in the system of the organic world. There is a taxonomy of animals, microorganisms, fungi and plants. In botany, a distinction is made between the taxonomy of lower plants and the taxonomy of higher plants.

Taxonomy- the most important branch of biology, including botany. Without systematics, the development of either theoretical or experimental botany (breeding, seed production, plant introduction, etc.) is unthinkable.

Any science is characterized by three components: the subject of study, the tasks that science sets for itself, and research methods. Taxonomy tasks are the description of plants, their names, classification and construction of the evolutionary system of the plant world. If earlier the tasks of plant taxonomy were to create a system of the plant world, establish a classification or distribute familiar forms into groups based on the study of their structure, assigning names to them in order to distinguish them, then at present the tasks of taxonomy are becoming much more complex. On the basis of evolutionary teaching, it is necessary to show the development of the entire plant world from the most ancient and primitive forms to the modern and most complex; install family ties, origin of plants, i.e. first of all, to give, if possible, a correct, harmonious picture of the development of the entire plant world, or its phylogeny, in which each species would have its place in the system in connection with other forms related to it. Plant taxonomy must be phylogenetic, reflecting not only the diversity of pre-existing and modern forms, but also their origin, connections and development throughout history organic life on Earth.

Thus, plant taxonomy consists of 3 sections:

1) taxonomy, that is, the theory and practice of plant classification;

2) nomenclature - totality existing titles taxa and the system of rules governing the establishment and use of these names;

3) phylogeny - establishes the relationship of plants in historical terms.

Every science has its own specific methods research, partly in common with other close and related disciplines. Currently, to build a phylogenetic system it is necessary to use the achievements of many related sciences - morphology, anatomy, embryology, paleobotany, ecology and geography of plants, biochemistry, genetics, etc. The application of the methods and achievements of these sciences in phylogenetic systematics is inevitable and mandatory. These methods can be divided into three main groups: morphological in a broad sense, physiological-biochemical and experimental-genetic.

The system that modern botanists use is hierarchical, built on the “box within a box” principle. Any level of the hierarchy is called a taxonomic rank (category). The hierarchy of taxa and the rules for naming plants (nomenclature) are regulated by the International Code of Botanical Nomenclature, which is mandatory for all botanists. Any level of taxa is called a taxonomy.

Plant nomenclature consists of designations of taxa (i.e., systematic units, or categories, to determine rank - for example, class, family, etc.) and names (for example, Anthophyta, Malus domestica). According to the code of botanical nomenclature, it is accepted next system taxonomic ranks (categories) (only the main ones are given).

With binary nomenclature, As has been customary since the time of Linnaeus, the Latin name of the species is followed by the abbreviated surname of the author of the species, i.e. the author who gave it the name according to the rule of priority. The surname of the author of the species for Linnaeus is indicated by one letter L., for example Rosa canina L. (i.e. Linnaeus), and for others it is indicated by several letters, for example D.C. (Decandolle), Max. (Maksimovich), etc.

As the main taxon– units of measurement organic nature, in particular plants, accepted form. The doctrine of species has a very big story, saturated with an intense struggle of conflicting views. The concept of species, as is known, was firmly applied and regulated for the first time in science by C. Linnaeus in his classic work “Species of Plants” (1753). The date of publication of this work determines the beginning of the scientific taxonomy of plants. However, the concept of a plant species as a systematic unit was expressed much earlier - first by K. Gesner (1559) and other researchers, and then by D. Ray in his “History of Plants” (1686-1704). The latter believed that the belonging of plants to the same species is determined by the possibility of their origin from the seeds of the same or similar plants. Despite the constancy of the species emphasized in this definition, D. Ray recognized its ability to change due to the degeneration of seeds. He even stated that “a transformation of species occurs in plants.”

K. Linnaeus, apparently, did not pay attention to Rey’s statements about the species and, in essence, did not give a definition of this basic systematic unit. He only said: “Species various forms exists as long as the infinite Being created,” i.e. God. Varieties, according to Linnaeus, are various plants, grown from seeds of the same species; they appear due to random reasons (climate, soil, etc.), and in the absence of these reasons, plants grow similar to the original parents. Species are divided into varieties and grouped into genera. “There are as many genera as there are different fruitings produced by natural species.” Further, K. Linnaeus said that “varieties are often works of culture, species and genera are creations of nature, and orders and classes are products of both nature and art.” Thus, he emphasized the partial artificiality of these latter systematic units.

Further research showed that the species identified by Linnaeus are not always the same. In many cases they represent a group of more or less stable hereditary systematic units and therefore the Linnaean species in these cases must be divided into a number of species. According to the definition given by academician V.L. Komarov, the view is “ morphological system, multiplied by geographical certainty”, i.e. type is determined morphological characteristics and a specific area. V.L. Komarov himself admitted that this is a formalistic definition, necessary only for practical work taxonomy. A species is a systematic category evolving in nature; it must be understood not statically, but dynamically, according to the law of universal change and development. Therefore, in a formulation that takes these points into account, V.L. Komarov (1945) said that “a species is a set of generations descending from common ancestor and under the influence of the environment and the struggle for the existence of living beings isolated by selection from the rest of the world; at the same time, a species is a certain stage in the process of evolution.”

In modern botany, as in science in general, it should be recognized that our knowledge is at its most initial stage explanations of nature. Science has acquired a “non-classical” (non-pragmatic) character. Non-classical character modern taxonomy manifested itself in understanding the species in plants. The long-standing debate about the criteria for “biological species”, i.e. natural species, created by nature itself and genetically isolated from each other, ended with the recognition that this category is not universal. It turned out that not all plant diversity is divided into “biological” species. Among self-pollinating organisms, there are microspecies - jordanones, there are hybridizing aggregates of "half-species" (singameons), there are "twin species" (morphologically similar, but genetically different) and "twin species" (morphologically different, but with the same genotype).

The concept of “taxonomic species” came into taxonomy, which denotes collections of plants of approximately the same volume. If there is " biological species", then the "taxonomic species" coincides with it in volume. If the totality of plants does not develop to such " good views", then the species are distinguished conditionally. They are difficult to identify even for an experienced botanist. For the same set of plants, different scientists today identify different numbers of species (in larger and smaller volumes) and group these species into different numbers of genera, families and orders. This causes frequent discussions and revisions of the taxonomy; the result is a unified understanding of the system. An example of such a collective agreement is two publications “Vascular Plants of the USSR” (1981) and “Vascular Plants of Russia and Neighboring States (within former USSR)" (1995). Author – S.K. Cherepanov.