Biological regress on the example of some plants and animals

Paleontology proved that many of the species that existed in the past disappeared completely.

Progress and regress in nature are opposite concepts. In the first case, the species develops and spreads around the planet. Biological regression is an evolutionary movement, characterized by a shrinking habitat, a decrease in the number of individuals due to inability to adapt. This process is accompanied by a decrease in the number of single group species due to pressure on them by others, as well as the disappearance of the species.

Biological regression is mainly associated with the loss of the ability of organisms to adapt in changing environmental conditions.

This movement is typical of parasitic organisms, immobile individuals and creatures living in caves or underground.

Biological regression can be considered by the example of parasites - flatworms. In the process of reverse development, they are simplified sensory organs, the digestive system, the nervous system. Along with this, there are various adaptations (hooks, suckers and others) necessary for keeping the host in the intestines. For example, a female crustacean, leading a parasitic way of life, completely lost all signs of arthropods, retaining only the function of laying eggs. Parasitizing bull body in the human body is capable of producing about eleven billion eggs protected by the host's body. Therefore, these worms are considered the most prolific.

Biological regression is also characteristic of plants. Just like in living organisms, their reverse development is closely related to parasitism. For example, there is a plant broomrape. It parasitizes on the root system of sunflower, clover, hemp. Zarazikha has darkish stems, and its scaly leaves do not contain chlorophyll. They are introduced into the stem of another plant with the help of suckers and suck nutrients from the body of the host.

For animals that remain immobile for life, the organ of motion functions exclusively during the larval stage. They have reduced their chord. To such organisms, in particular, is the pogonophora - a representative of a separate type of brachyate. These individuals are not very similar to animals. They live on the seabed and live motionless. Pogonophora has a heart and a brain, however, the stomach and the mouth of it are reduced. Tentacles are respiratory organs. Inside, there are long hairs, provided with blood vessels. They gradually accumulate microorganisms. When they (micro-organisms) become many, the epipharypie tightens the hairs inside. Under the influence of special enzymes, the smallest organisms are digested and absorbed into internal outgrowths. The presence of an embryonic intestine proves the existence of this organ in the ancestors of Pogonophora. But in connection with the fact that the process of digestion is carried out outside the body, the organs of the digestive tract were reduced.

The regression of animals living underground or in caves can be considered using the example of a proteus. This is a representative of the amphibian class, similar to the newt. This animal lives in caves. On his head on both sides he has external gills. Proteus can breathe both in water and on land. In the first case, he uses the gills, and in the second - the lungs. Since Proteus dwells in deepwater caves, it has a serpentine shape. His body is clear, colorless, has no pigments. In adults, the organs of vision are covered with skin, larvae have rudimentary eyes. There are two pairs of underdeveloped limbs on the body of the proteus.

A genetic mutation is the genetic basis for evolutionary changes leading to the simplification of the organizational level.

In the development of the organic world there are three directions. Aromorphosis characterizes the increase in the level of organization of organisms. Idioadaptation is an adaptation to environmental conditions without fundamental changes in the biological structure. General degeneration is a simplification of the level of organization of living beings.