EVOLUTION (in biology) EVOLUTION (in biology)

EVOLUTION (in biology), irreversible historical development of living nature. Determined by variability (cm. VARIABILITY), heredity (cm. HEREDITY) and natural selection (cm. NATURAL SELECTION) organisms. Accompanied by their adaptation to living conditions, the formation and extinction of species, the transformation of biogeocenoses (cm. BIOGEOCENOSIS) and the biosphere as a whole.

encyclopedic Dictionary . 2009 .

See what “EVOLUTION (in biology)” is in other dictionaries:

It has a double meaning. Usually this term is understood in the same way as in philosophy, that is, it means the development of one form from another, and E. in the general biological sense is synonymous with transformism (see). But, in addition, the theory of E.... ... Encyclopedic Dictionary F.A. Brockhaus and I.A. Efron

- (in biology) the irreversible historical development of living nature. Determined by variability, heredity and natural selection of organisms. Accompanied by their adaptation to living conditions, the formation and extinction of species... ... Big Encyclopedic Dictionary

- (from Latin evolutio deployment), in a broad sense synonymous with development; processes of change (in the sense of irreversible) occurring in living and inanimate nature, as well as in social systems. E. can lead to complication, differentiation, increase... ... Philosophical Encyclopedia

The development of organisms from lower levels of organization of living things to modern highly organized forms; irreversible changes in the diversity and adaptation of species populations; expression of successive genetic transformations (changes);… … Ecological dictionary

- (from Latin evolutio deployment), an irreversible historical process. changes in living things. Of the many undirected mutations as an elementary evolution. material, natural selection forms such combinations of characteristics and properties that lead to... ... Biological encyclopedic dictionary

Changes in adaptive traits and forms of adaptation of populations of organisms. The first consistent theory of E. b. was put forward in 1809 fr. naturalist and philosopher J.B. Lamarck. To explain the progressive development in nature over time, this... ... Philosophical Encyclopedia

Biological evolution, historical development of organisms. Determined by hereditary variability, the struggle for existence, natural and artificial selection. Leads to the formation of adaptations (adaptations) of organisms to their conditions... ... Great Soviet Encyclopedia

This article is about biological evolution. For other meanings of the term in the title of the article, see Evolution (meanings). Fi... Wikipedia

Evolutionary doctrine (also evolutionism and evolutionism) is a system of ideas and concepts in biology that affirm the historical progressive development of the Earth’s biosphere, its constituent biogeocenoses, as well as individual taxa and species, which can be ... Wikipedia

Anthropogenesis (or anthroposociogenesis) is part of biological evolution that led to the emergence of a species Homo sapiens, separated from other hominids, great apes and placental mammals, the process of historical evolutionary formation ... Wikipedia

Books

• Evolution of ontogeny, Ozernyuk N.D.. The evolution of ontogeny is considered as the main problem of evolutionary developmental biology, since the evolutionary transformations of organisms are caused by changes in their ontogenesis. Integration…

The offspring of living beings are very similar to their parents. However, if the environment of living organisms changes, they can also change significantly. For example, if the climate gradually becomes colder, then some species may acquire increasingly thick hair from generation to generation. This process is called evolution. Over millions of years of evolution, small changes, accumulating, can lead to the emergence of new species of plants and animals that differ sharply from their ancestors.

How does evolution happen?

Evolution is based on natural selection. It happens like this. All animals or plants belonging to the same species are still slightly different from each other. Some of these differences allow their owners to better adapt to living conditions than their relatives. For example, some deer especially quick legs, and he manages to escape from the predator every time. Such a deer has a better chance of surviving and having offspring, and the ability to run quickly can be passed on to its cubs, or, as they say, inherited by them.

Evolution has created countless ways to adapt to the difficulties and dangers of life on Earth. For example, seeds horse chestnut Over time, they acquired a shell covered with sharp spines. The spines protect the seed as it falls from the tree to the ground.

What is the rate of evolution?

Previously, these butterflies had light wings. They hid from enemies on tree trunks with the same light bark. However, about 1% of these butterflies had dark wings. Naturally, the birds noticed them immediately and, as a rule, ate them before others

Usually evolution proceeds very slowly. But there are cases when a species of animal undergoes rapid changes and spends not thousands and millions of years on this, but much less. For example, some butterflies have changed their color over the past two hundred years to adapt to new living conditions in areas of Europe where many industrial enterprises have arisen.

About two hundred years ago in Western Europe began to build coal-fired factories. The smoke from the factory chimneys contained soot, which settled on the tree trunks, and they turned black. Now the light-colored butterflies are more noticeable. But few butterflies with dark wings survived, because the birds no longer noticed them. From them came other butterflies with the same dark wings. And now most butterflies of this species living in industrial areas have dark wings.

Why do some animal species become extinct?

Some living things are unable to evolve when their environment changes dramatically, and die out as a result. For example, huge hairy animals similar to elephants - mammoths, most likely became extinct because the climate on Earth at that time became more contrasting: it was too hot in summer and too cold in winter. In addition, their numbers have decreased due to increased hunting for them. primitive man. And after the mammoths, saber-toothed tigers also became extinct - after all, their huge fangs were adapted to hunting only large animals like mammoths. Smaller animals were inaccessible to saber-toothed tigers, and, left without prey, they disappeared from the face of our planet.

How do we know that man also evolved?

Most scientists believe that humans evolved from tree-dwelling animals similar to modern monkeys. The proof of this theory is provided by certain structural features of our bodies, which allow us, in particular, to assume that our ancestors were once vegetarians and ate only fruits, roots and stems of plants.

At the base of your spine there is a bone formation called the tailbone. This is all that remains of the tail. Most of the hair covering your body is just soft fuzz, but our ancestors had much thicker hair. Each hair is equipped with a special muscle and stands on end when you are cold. It’s the same with all mammals with hairy skin: it retains air, which prevents the animal’s heat from escaping.

Many adults have wide outer teeth—they are called “wisdom teeth.” Now there is no need for these teeth, but at one time our ancestors used them to chew the tough plant foods they ate. The appendix is ​​a small tube connected to the intestines. Our distant ancestors used it to digest plant foods that were poorly digestible by the body. Now it is no longer needed and is gradually becoming less and less. In many herbivores - for example, rabbits - the appendix is ​​very well developed.

Can humans control evolution?

People drive evolution some animals have been around for over 10,000 years. For example, many modern breeds of dogs, in all likelihood, descended from wolves, packs of which roamed around the camps of ancient people. Gradually, those of them that began to live with people evolved into the new kind animals, that is, they became dogs. Then people began to specifically raise dogs for specific purposes. This is called selection. As a result, today there are over 150 various breeds dogs.

• Dogs that could be taught various commands, like this English Sheepdog, were bred to herd livestock.
• Dogs that could run fast were used to chase game. This greyhound has powerful legs and runs with huge leaps.
• Dogs with a good sense of smell were bred specifically for tracking game. This smooth-haired dachshund can tear apart rabbit holes.

Natural selection usually proceeds very slowly. Selective selection allows you to dramatically speed it up.

What is genetic engineering?

In the 70s XX century scientists have invented a way to change the properties of living organisms by interfering with them genetic code. This technology is called genetic engineering. Genes carry a kind of biological code contained in every living cell. It determines the dimensions and appearance every living being. Genetic engineering can be used to create plants and animals that, say, grow faster or are less susceptible to some disease

Nature improves itself all the time. But evolutionary changes occur extremely slowly. Compared to human life, of course. Only over billions of years of the Earth’s existence was nature able to achieve such perfection and diversity of life as we see now.

Darwin suggested that the driving forces of evolution, or factors influencing the development of living nature, are:

• heredity and variability of individuals of one species;

Heredity and variability

It is known that individuals of the same species are similar, but still not the same. They differ slightly in terms of appearance and internal structure, behavior. These differences may influence the possibility of survival. Those individuals have a greater chance of surviving and leaving offspring. features which correspond to the habitat. These changes can be inherited by offspring. As a result, the number of individuals with such characteristics increases in the next generation.

Struggle for existence

Adaptations are features of living organisms, thanks to which they exist in nature. Useful traits, arising in individual organisms as a result of variability, help them survive in the struggle for existence. These characteristics are preserved as a result of natural selection and are inherited by descendants. So, generation after generation, the characteristics of animals and plants gradually change for the better for them. evolutionary changes. And that is why all living organisms are so well adapted to the conditions in which they live.

Speciation

Speciation is the result of evolution. Over the course of many generations, a population can be isolated from other populations of a given species (for example, be located at a distance from them long distance). Acting long time, natural selection leads to the accumulation of many differences between the isolated and other populations.

As a result, individuals from different populations lose the ability to interbreed and produce offspring. The emergence of insurmountable biological barriers to crossing leads to the process of speciation.

Speciation led to the emergence of two species of foxes - the common fox and the corsac fox. In the north, natural selection favored the survival of the largest individuals (than larger size body, the less heat the body loses). As a result, the species Common fox was formed. In the southern regions, on the contrary, natural selection was aimed at preserving the smallest individuals (than smaller size body, the more heat the body gives off without overheating). As a result, the species Corsac fox was formed.

To date, biological evolution has been fully confirmed based on scientific facts accumulated in various branches of biological science. Evidence of evolution is based on a comparative study of the external and internal structure, development and life processes of modern representatives of ancient extinct species. For this purpose there are scientifically based cytological,

The historical development of living nature occurs according to certain laws and is characterized by a set of individual characteristics. The successes of biology in the first half of the 19th century served as a prerequisite for the creation of a new science - evolutionary biology. She immediately became popular. And she proved that evolution in biology is a deterministic and irreversible process of development as individual species, and their entire communities - populations. It occurs in the Earth's biosphere, affecting all its shells. This article will focus on how to study the concepts biological species, so

History of the development of evolutionary views

Science has passed difficult path formation of ideological ideas about the mechanisms underlying the nature of our planet. It began with the ideas of creationism expressed by C. Linnaeus, J. Cuvier, and C. Lyele. The first evolutionary hypothesis was presented by the French scientist Lamarck in his work “Philosophy of Zoology”. The English researcher Charles Darwin was the first in science to express the idea that evolution in biology is a process based on hereditary variability and natural selection. Its basis is the struggle for existence.

Darwin believed that the emergence of continuous changes in biological species is the result of their adaptation to constant changes in environmental factors. The struggle for existence, according to the scientist, is a set of relationships between the organism and the surrounding nature. And its reason lies in the desire of living beings to increase their numbers and expand their habitats. All of the above factors include evolution. Biology, which the 9th grade studies in class, examines the processes of hereditary variability and natural selection in the section “Evolutionary Doctrine”.

Synthetic hypothesis of the development of the organic world

Even during the life of Charles Darwin, his ideas were criticized by a number of such famous scientists as F. Jenkin and G. Spencer. In the 20th century, due to the turbulent genetic research and the postulation of Mendel's laws of heredity, it became possible to create a synthetic hypothesis of evolution. In their works it was described by such people as S. Chetverikov, D. Haldane and S. Ride. They argued that evolution in biology is a phenomenon of biological progress that takes the form of aromorphoses, idioadaptations, affecting populations of various species.

According to this hypothesis, the evolutionary factors are waves of life and isolation. Forms historical development nature are manifested in processes such as speciation, microevolution and macroevolution. The above scientific views can be represented as a summation of knowledge about mutations that are the source of hereditary variability. As well as ideas about the population as a structural unit of the historical development of a biological species.

What is an evolutionary environment?

This term is understood as biogeocenotic. Microevolutionary processes occur in it, affecting populations of the same species. As a result, the emergence of subspecies and new biological species becomes possible. Processes leading to the emergence of taxa - genera, families, classes - are also observed here. They relate to macroevolution. Scientific research V. Vernadsky, proving the close relationship of all levels of organization of living matter in the biosphere, confirm the fact that biogeocenosis is an environment of evolutionary processes.

In climax, that is, stable ecosystems in which there is a large diversity of populations of many classes, changes occur due to coherent evolution. in such stable biogeocenoses they are called coenophilic. And in systems with unstable conditions, uncoordinated evolution occurs among ecologically plastic, so-called coenophobic species. Migration of individuals from different populations of the same species alters their gene pools, disrupting the frequency of occurrence of different genes. This is what modern biology thinks. The evolution of the organic world, which we will consider below, confirms this fact.

Stages of development of nature

Scientists such as S. Razumovsky and V. Krasilov have proven that the pace of evolution underlying the development of nature is uneven. They represent slow and almost imperceptible changes in stable biogeocenoses. They sharply accelerate during periods of environmental crises: man-made disasters, melting glaciers, etc. The modern biosphere is home to about 3 million species of living beings. The most important of them for human life are studied in biology (grade 7). The evolution of Protozoa, Coelenterates, Arthropods, Chordata represents a gradual complication of the circulatory, respiratory, nervous systems these animals.

The first remains of living organisms are found in Archean sedimentary rocks. Their age is about 2.5 billion years. The first eukaryotes appeared at the beginning Possible options the origin of multicellular organisms is explained scientific hypotheses phagocytella of I. Mechnikov and gastrea of ​​E. Goetell. Evolution in biology is the path of development of living nature from the first Archean life forms to the diversity of flora and fauna of the modern Cenozoic era.

Modern ideas about the factors of evolution

They represent conditions that cause adaptive changes in organisms. Their genotype is most protected from external influences (conservativeness of the gene pool of the biological species). Hereditary information can still change under the influence of genetic information. It is in this way - through the acquisition of new characteristics and properties - that the evolution of animals took place. Biology studies it in such sections as comparative anatomy, biogeography and genetics. Reproduction, as a factor of evolution, is of exceptional importance. It ensures the change of generations and continuity of life.

Man and the biosphere

Biology studies the processes of the formation of the Earth's shells and the geochemical activity of living organisms. The evolution of the biosphere of our planet has a long history geological history. It was developed by V. Vernadsky in his teaching. He also introduced the term “noosphere”, meaning by it the influence of conscious (mental) human activity on nature. Living matter, included in all the shells of the planet, changes them and determines the circulation of substances and energy.

Biological evolution is defined as any genetic change in a population that occurs over several generations. These changes may be small or large, very noticeable or not significant.

For an event to be considered an example of evolution, changes must occur at the genetic level of the species and be passed on from one generation to the next. This means that , or more specifically, alleles in a population change and are passed on. These changes are noted in the (pronounced physical features that can be seen) of the population.

Change genetic level population is defined as small-scale change and is called microevolution. Biological evolution also includes the idea that all living organisms are related and can descend from a common ancestor. This is called macroevolution.

What is not biological evolution?

Biological evolution does not determine the simple change of organisms over time. Many living things experience changes over time, such as loss or increase in size. These changes are not considered examples of evolution because they are not genetic and cannot be passed on to the next generation.

Evolution theory

How does genetic diversity occur in a population?

Sexual reproduction can create favorable combinations of genes in a population or remove unfavorable ones.

A population with more favorable genetic combinations will survive in its environment and reproduce more offspring than individuals with less favorable genetic combinations.

Biological evolution and creationism

The theory of evolution has generated controversy since its inception, which continues to this day. Biological evolution contradicts religion regarding the need for a divine creator. Evolutionists argue that evolution does not address the question of whether God exists, but rather attempts to explain how natural processes occur.

However, there is no escaping the fact that evolution contradicts some aspects of certain religious beliefs. For example, the evolutionary account of the existence of life and the biblical account of creation are completely different.

Evolution suggests that all life is connected and can be traced back to a single common ancestor. A literal interpretation of biblical creation suggests that life was created by the omnipotent supernatural being(by God).

However, others have tried to combine the two, arguing that evolution does not rule out the possibility of God, but simply explains the process by which God created life. However, this view still contradicts the literal interpretation of creativity presented in the Bible.

For the most part, evolutionists and creationists agree that microevolution does exist and is visible in nature.

However, macroevolution refers to the process of evolution that is at the species level, where one species evolves from another species. This is in sharp contrast to the biblical view that God was personally involved in the formation and creation of living organisms.

For now, the evolution/creationism debate continues, and it appears that the differences between the two views are unlikely to be resolved anytime soon.

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