The fitness of the organisms is the result of evolution factors.
Relative character of adaptations

11th (9th) class (2 h)

Lesson 1. "Adaptive features of organisms"

Methodical support

The lesson is built using the Spiral Technology, which is an integral part of the technology critical thinking. The purpose of it is applied:

- activation of the mental activity of students in the lessons;
- Formation of the skills of obtaining information from various sources, skills to compare and analyze the material being studied.

This technique allows you to analyze the material being studied as far as possible at different levels of perception, which forms more strong knowledge.

Stages of work:

- creating a problem situation;
- Individual work of students with cards, follow-up joint discussion and formulating intermediate conclusions;
- work of students in pairs with text, drawing up a working table;
- a collective discussion of the information set out in the text;
- Teacher's story, making additions to the table, formulating the final conclusions;
- drawing up an individual report.

Planned Result: Students expand and systematize knowledge of the adaptive features of organisms.

Training method- Problem: What is the difference between changes from fixtures? Why organisms (species) are surprisingly well adapted to the conditions ambient?

Materials for lesson:

- 12 cards with examples of adaptations of different types;
- text "Adaptive Features of Organizations";
- Sample table for filling.

Check the performance of the lesson: assessments of students for individual and paired work; Selective reporting; Through a lesson - Blitz test (biological labyrinth) for 10 minutes.

DURING THE CLASSES

To survive, you need to quickly change.

L. Carroll ("Alice in the Wonderland")

Formulation of the problem

Example 1. On the scholars, the scholars attached to the spikes in the grass cleaned from the grass, tied three colors of the brown, yellow, green. During your experience, the birds were destroyed by 60% of yellow, 55% of the green and only 20% of the brown bears, who had color color coincided with the color of the background.
Similar experiments were delivered with pupae butterflies. In case of inconsistencies in the color of the pupae coloring the background of the bird destroyed much more dolls than in the case of coincidence of the background with the color.
Waterfowl in the pool caught a predominantly fish, the color of which does not correspond to the color of the bottom.

Questions

What could be found with the help of the described experiments?

What was the survival rate of the Bogomolov, the pupa of butterflies and fish?

How can I explain the results of experiments received by scientists?

(Oral mini conclusions).

Example 2. Everyone knows that the roots of the plants grow down, penetrating the soil. However, in the jungle of Venezuela, 12 types of trees were discovered, the roots of which climbed up the trunk.
What could be the cause of "strange behavior" of the roots?

(Schoolchildren answer options).

(Control response for the teacher: Soil in these places contains so few nutrients that the roots have adapted to choose ions of Ca, Mg, K, etc. Elements flowing on the trunk of rainwater. To confirm this assumption, researchers artificially increased the content of mineral substances in flowing water. The growth of the roots after that intensified).

Primary understanding of the lesson theme (recording on the board):

Fitness of organisms

The adaptability of the organisms (from the lat. "Adaptation" is a device) - the ability of organisms to resist the reeddance of environmental conditions.

The teacher distributes cards (each even party reads even examples, odd, respectively - odd) and proposes to perform the task:

- Read the proposed examples.
- Try to determine the types of adaptation.
- Break these examples into groups, explain your choice.

Card 1. IN South America About 10 species of slogans live - strictly wood animals. The normal position of the body of these extremely slow creatures is hanging back down. In contrast to all the rest of the mammal, the fur of the sloths on the torso is not directed from the back to the belly, but, on the contrary, with a belly to the back. On a loose, the algae, giving the animal green color, which gives him to be hidden in foliage.

Card 2. The caterpillars of the spiders, clinging to the branch by the rear pairs of feet and flexing the rest of the body at an angle to it, the bitch is likened. Some mantis color and body shape are similar to those or other parts of the flower, so they are called floral.

Card 3. Breidy's English entomistist, who studied the behavior of Tsetz Fly, came to the conclusion that she attacks any moving warm object, even a car. Muha not attacks only on Zebra, which perceives only as the flashes of black and white stripes.

Card 4. Beetle-bombarder produces chemical substanceswho, at a danger, enter the funk-like department of the rear of his body. There begins a stormy reaction, and the resulting unpleasant fluid, blowing up, is thrown directly on the attacker. The usual driver "rewards" a predator with a liquid, which causes Naryavy.

Card 5. Along the coast of the Australian province Queensland and near Sydney lives a very poisonous octopus. Although its sizes rarely exceed 12 cm, poison in it is enough to kill 10 people.

Card 6. Some animals use the smell as protection: North American skuns is able to throw a stream of badly smelling fluid by 3 m with striking accuracy. It can temporarily blindfooting and definitely understand him from a re-attack on skunk.

Card 7. Covered by concentrating stripes, but completely harmless fly - hovering extracts nectar from a flower, like honey bees, possessing a terrible sting. Imitation of the Burchable is not limited to the color, but includes behavior. Burbed imitate the sounds, published by bees and axes, and, if you disturb them, threateningly buzz.

Card 8. Australian bearded lizard is capable of scaring a brave predator self-brave. She loudly whistles, hits the tail and raises the ridge so that it seems 4 times more than it really is.

Card 9. In some cases, fish can be masked under other animals, and they make it collectively. For example, small marine catches, finding what is approaching them predatory Fish, immediately grouped into a kind of girl's sembrella. Their heads turn out to be in the center of this "architectural structure", and pointed tails stick out out. They published the "tangle" resembles a barbed sea hedgehog, which predators prefer to bypass the party.

Card 10. IN african savannah Lives a small underground rodent - naked farm. This is a strange, almost naked, deprived of the Created Creation. That is more fun to see Vibrisa sticking in different directions - on the head and on the belly. Numerous sensitive hairs help excav workers to navigate in huge underground labyrinths laid by these hardworking animals.

Card 11. Some hedgehogs use the allocations of poisonous toads to lubricate their needles. Attacking the toad, hedgehog, first of all, biting her poisonous parole glands, and then the poisoned saliva lubricates its needles. Cunning habits are absorbed in childhood. The newborn, even blindly licks a poisonous lubricant with a needle of a mother and inflicts her tongue to his still soft needles.

Card 12.Animals per minute danger often resort to different tricks: especially the birds do it - pretending to be wounded, they distract predators from the nests. Even such large animals as elephants are able to deceive predatory
Cove - they are also pretending, only dead.

One day in the jungle of India caught a wild elephant. It was tied with chains. Suddenly the elephant fell to the ground. The hunters tried to extract him, but he lay motionless. They decided that the elephant died, removed the chains and left him. The elephant jumped on his feet and rushed to run.

Following the discussion on the board there is a record of those options for adaptation that found students in the examples.

Reading and organizing text

Teacher: To find out what other adaptations are found in nature, get acquainted with the following text, prepare a table to summarize and make brief records in it. Work under the same conditions as in the previous case: each even party reads about plants; Each odd - about animals.

Text "Adaptive Features of Organisms"

One of the results of natural selection that is a guide driving power The process of evolution, it is possible to name the development of all living organisms of adaptations - accessories to the habitat.

The variety of specific devices can be divided into several groups that are forms of fitness of organisms to the environment.

Some forms of fitness in plants

• Adaptations to elevated dryness: the input of the leaves, the accumulation of moisture in the stem (cactus, baobab), the conversion of leaves in the needles (coniferous plants).

• Adaptations to high humidity: a large surface of the sheet, a lot of stomits, an increased intensity of evaporation.

• Fixtures to pollination by the wind: render of stamens with anthers far beyond the flower, small light pollen, the pestle is strongly omitted, petals and cups are not developed, do not interfere with the blowing of other parts of the flower by the wind.

• Fitness to pollination insects: bright attracting flower color, the presence of nectar, smell, flower shape.

• Adaptations to the settlement and distribution of seeds and disputes: juicy, attractive fruits or cones for animals; Seeds with stealing, wipers, hooks, parachutes; Light numerous disputes; "Exploding" fruits (loft, "mad" cucumber).

• Adaptations to the maximum amount of light: sheet mosaic, flat wide leaves, multi-layered columnar and spongy photosynthetic fabric, narrow interclausers, a large amount of chlorophyll.

• Adaptations to the transfer of unfavorable conditions: leaf fall; Power supply of nutrients in bulbs, rhizomes, tubers, root plans; Efhemerity (snowdrops, crocuses, proleski).

• Adaptations to a lack of nutrition or oxygen: insectoity (Rosyanka, Veineree Mukholovka); Air roots (orchids); Respiratory roots (Mangra).

• Damage from eating herbivores: Needles; spines; Druz (potassium oxeline crystals) accumulating in spines or leaves; poisonous juices; Claiming cells with burning hairs.

Some forms of fitness in animals

• Body shape:

- Torpedo-shaped (prevents the formation of curvatures of water flows when driving): sharks, dolphins, penguins, squid;
- Imprive (makes an organism invisible among certain objects): Distributions, Padenic Caterpillars, Tsicades, Sea Skates, Funns;
- Flavored (for life at the bottom or in narrow crevices): Planaria, Fambal, Skates.

Body coloring:

- warning (at species possessing poisonous, burning, stinging structures): wasps, bumblebees, bees, beetles, breakdowns, caterpillars of cabbage butterflies, ladybugs, rattle snakes;
- Pontreamious (hides against the background of the environment): Green grasshopper, white owl, flounder, octopus, hare of white, Wolley, white partridge;
- Dismembering, "camouflage" (blurs the contours, helps to remain invisible against the background of an inhomogeneous medium, among stains and light and shadow bands): zebras, tigers, spotted young deer, giraffes, zebra fish.

Adaptation at which the body shape and coloring of the animal merge with the surrounding objects, is called maskirovka.
Imitation of well-protected and possessing the warning color or, on the contrary, harmless animals, helps potential victims to protect against eating predators and is called mimicria..

Table. Adaptation of organisms

Indicators of fitness	Animals	Plants
1. Adaptations to abiotic factors (for example, cold)	1. thick wool 2. Fat subcutaneous layer of fat 3. Flight to South 4. Winter hibernation 5. Painting feed for the winter	1. Listopad 2. Cool resistance 3. Preservation of vegetative organs in the soil 4. The presence of modifications (bulbs, rhizomes, etc. with nutrient reserves)
2. Food Methods	For mining food and water: 1. Communication of leaves at high trees (long neck) 2. Capture with the help of networks (weaving web and the creation of other diverse traps) and tuning power facilities 3. The special structure of the digestive organs for catching insects from narrow holes, whispering of grass, fishing of flying insects, multiple peeling of coarse food (sticky long language, multi-chamber stomach, etc.) 4. Grappling and retention of prey with predatory mammals and birds (predatory teeth, claws, hooked beak)	To mining biogenic, water and energy: 1. Absorption of water and mineral substances (intensive development of roots and root hairs) 2. Wide fine leaves, sheet mosaic (solar energy absorption) 3. Water stocking (thick network of interclausers, thickened stem and others.) 4. Capture and digestion of small animals (insectoral plants), etc.
3. Protection against enemies	1. Quick run 2. Needles, shell 3. Scare up the smell 4. Pontroval, warning, etc. Types of color	1. Spinys 2. Outlet form, inaccessible to boom (mowing) 3. Poisonous substances 4. Clamping cells
4. Ensuring the effectiveness of reproduction	Attracting sexual partner: 1. Bright plumage 2. "Crown" Rogov 3. Sex attractants 4. Songs 5. Marriage dancing	Attracting the pollinator: 1. Nettle 2. Pollen 3. Bright coloring of flowers or inflorescence 4. Smell
5. Requirements for new territories	Migration: The movement of herd, colonies, flocks in search of food and suitable conditions for breeding (birds flying, nomads antelope, zebras, fish swims)	Spreading seeds and dispute: 1. Chain hooks, spines 2. Khokholki, Wolfings, Freaks for the transfer of the wind 3. Juicy fruits, etc.

Examples:

- Mukho-hoverings look like bees, OS, bumblebees;
- innocuous tropical merges are similar to poisonous snakes;
- Eggs, laid by the cuckoo, correspond to the color of the eggs of the owner's birds, etc.

Solid bodies of body, spikes and needles ( mechanical protection From a predator): sea hedgehog, beetles, crabs, snails and bivalve mollusks, turtles, hedgehogs, dickerages).

Poisonous glands or toxins (for the victim - protection against eating; for predators - means of killing or immobilization of production): jellyfish, spiders, multi-peas, some fish, many amphibians, snakes.

Physiological adaptation:

- Removal of excess water through the kidneys in the form of a weakly concentrated urine (maintaining the constancy of the inner environment of the body in low water conditions): freshwater fish and amphibious;
- Isolation of a small amount of strongly concentrated urine (maintaining the constancy of the inner environment of the body in terms of living in a hyperosmotic medium or in the desert): marine fish, sea snakes, desert rodents.
- The ability to echo, thermo- and electrolocation (for orientation in space): bats, dolphins, some snakes (they differ in the distance of objects whose body temperature differs from the temperature of the medium only 0.2 ° C), fish.

There are many other types of physiological adaptations, for example, the ability to fall into the hibernation, the ability of body fluids to resist freezing, the ability to bypass a small amount of oxygen, etc.

Adaptive behavior:

- repellent (protection against predators): Eared roundhead, bearded lizard, owls;
- Fooling (Protection against predators): Opossula, some beetles, amphibians, birds;
- stocking (many animals spare food for unfavorable season of the year): Keedrovka, Coyake, Chipmunk, Protein, Food;
- migration (avoiding adverse conditions by moving to other areas): migratory birds, some types of butterflies.

There are many other types of adaptive behavior. For example, in the desert for many species, the time of the greatest activity is the night when the heat falls.

Caring for offspring:

- tooling caviar on the body or in the oral cavity: crustaceans, sea skates, tilapia, Suriname Pipe;
- the construction of the nest and the elimination of it in it: some amphibians and fish (barbons, cocks, macropods), birds, all placental mammals that born helpless young;
- Feeding offspring: wasps, bees, ants, some fish (discs), birds, mammals. Scratis beetles and single wasps do not roll out the larvae, but provide them with a food margin.

According to the results of the text discussion, a table is drawn up (see p. 18).

Summing up the lesson

Plants and animals are surprisingly adapted to the conditions of the medium in which they live. The concept of "fitness of the species" includes not only external signs, but also the correspondence of the structure of the internal organs by them by the functions (for example, a long and complexly organized digestive tract of ruminant animals feeding on vegetation food).

Compliance of the physiological functions of the body conditions of its habitat, their complexity and diversity also enters the concept of fitness.

Think of which output should be made from the above, discuss in pairs, make entries in your reports.

Homework

• Option 1. Think and write down in the notebook signs of mutual facilities of predators and victims.

To be continued

"The fitness of the organisms and education of new species"

1. The fitness of the organisms and its relativity

In XIX. studies brought all new data that reveal the fitness of animals and plants to environmental conditions; The question of the causes of this perfection of the organic world remained open. Darwin explained the origin of fitness in the organic world with the help of natural selection.

We will get acquainted with some facts testifying to the adaptability of animals and plants.

Examples of fitness in the animal world. In the animal world is widespread various forms protective coloring. They can be reduced to three types: patronizing, warning, camouflage.

Protective coloration Helps the body to become less noticeable against the background of the surrounding area. Among the green vegetation of bugs, flies, grasshoppers and other insects are often painted in green. Fauna of the Far North ( polar bear, Polar hare, white partridge) characterizes white painting. The deserts predominate yellow tones of painting animals (snakes, lizards, antelopes, lions).

Warning color Clearly distinguishes the body in the environment with bright, motley stripes, stains (forged 2). It is found in poisonous, burning or staggering insects: bumblebees, OS, bees, beetles-failures. Bright, warning color usually accompanies other means of protection: hairs, spikes, sting, caustic or acutely smelling liquids. The same type of coloring is threatening.

Disguise It can be achieved similarity on the shape of the body and color with any object: a sheet, branch, bitch, stone, etc. With the danger of the caterpillar of the butterfly, the spiders pulls out and frozen on the branch like a bitch. Butterfly scoop-rotels in a fixed state easily take for a piece of rotten tree. Masking is also achieved mimicria. Under mimicria, they mean similarities in coloring, body shape and even in behavior and habits between two or several types of organisms. For example, the bumblebee prominent and dyeing flies, devoid of sting, are very similar to our our own insects.

It should not be thought that protective coloring necessarily and always saves animals from extermination by enemies. But more adapted by the color of the organisms or groups of them die much less frequently than less adapted.

Along with the protective coloring, animals have developed many other adaptations to the living conditions, expressed in their habits, instincts, behavior. For example, quail in the case of danger rapidly falls on the field and freeze in a fixed pose. In the deserts of the snake, lizards, beetles are hiding from heat in the sand. At the time of danger, many animals take 16 threatening postures.

Examples of fitness in plants. High trees whose crowns freely blows the wind, as a rule, have fruits and seeds with stealing. For undergrowth and shrubs where birds live are bright, with edible pulp fruits. Many meadow herbs have fruits and seeds have hooks with which they are traying to mammalian wool.

A variety of devices prevent self-pollution and ensure cross-pollination of plants.

Odnodomal plants have men and women's flowers not at the same time (cucumbers). Plants with routine flowers are protected from self-pollution by the patterns of stamens and pestles or the characteristics of their structure and mutual location (at the primrose).

We also point out examples: delicate sprouts of spring plants - anemone, cleaning, blue transfer, goose bow and other temperatures below zero due to the presence of a concentrated sugar solution in cellular juice. Very slow growth, lowerness, meltsomeness, surface location of the roots in trees and shrubs in Tundra (Iva, Birch, Juniper), the extremely rapid development of polar flora in spring and summer - all this adaptations to life in the conditions of permafrost.

Many weighing plants produce an immeasurably more seeds than cultural, is an adaptive sign.

Manifold fixtures. Types of plants and animals are characterized by adaptability not only to the conditions of the inorganic medium, but also to each other. For example, in wide forest Herbal cover in the spring form light-loving plants (christmas, anemone, median, cleaning), and in summer - shadowless (butders, lily of the village, Zelenchuk). Pollinkers of the Rannetic Plants are mainly bees, bumblebees and butterflies; Summer flowering plants are usually pollinated by flies. Numerous insectivore birds (Ivolga, rapid), nesting in a wide forest, destroy his pests.

In the same habitat, organisms have various devices. The bird of Olenipa does not have a swimming membrane, although it makes it a food like a water, diving, using wings and clinging her legs behind the stones. The Mole and Plesh belong to the woven animals, but the first root limbs, and the second moves underground moves with head and strong cutters. The seal floats with the help of flops, and the dolphin uses the tailflower.

The origin of devices in organisms. An explanation of the emergence of complex diverse tools to specific environmental conditions given by Darwin was radically distinguished from understanding this issue by Lamarcom. These scientists also dispersed also in determining the main driving forces of evolution.

Darwin's theory It gives a completely logical materialistic explanation of origin, for example, a patronage color. Consider the occurrence of green body of caterpillars living on green leaves. The ancestors could be painted in any other color and do not eat leaves. Suppose that, due to some circumstances, they were forced to switch to meals with green leaves. It is easy to imagine that the birds missed many of these insects, well visible on a green background. Among the various hereditary changes that are always observed in the offspring, there could be changes in the color of the body of the caterpillars who made them less noticeable on green leaves. From the number of caterpillars with a greenish tint some individuals preserved and gave a prolific offspring. In subsequent generations, the process of preferential survival of caterpillars, less visible in green leaves continued. Over time, thanks to the natural selection of the green color of the caterpillage body, more and more matched the main background.

The occurrence of mimicry can also be explained only by natural selection. Organisms with the slightest deviations in the shape of the body, color, behavior, reinforcing similarity with protected animals, had more opportunities to survive and leave numerous offspring. The percentage of death of such organisms was lower than those who did not possess useful changes. From generation to generation, a useful change intensified and improved through the accumulation of signs of similarities with protected animals.

Driving power of evolution - natural selection.

Lamarc Theory It turned out to be completely helpless in explaining organic feasibility, for example, the origin of various types of protective color. It is impossible to assume that animals "practiced" in the color or body company and the exercise acquired the adaptation. It is impossible to explain the mutual fitness of the organisms to each other. For example, completely inexplicably the emergence of the conformity of the trunk in the working bees of the structure of the flower of certain types of plants pollinated by them. Working bees do not multiply, and bee uterus, although they produce offspring, but cannot "exercise" trull, as they do not collect pollen.

Recall the driving forces of the evolution of the LAMARK: 1) "The desire of nature to progress", as a result organic world Develops from simple forms to complex, and 2) Changing action external environment (directly on plants and lower animals and indirect with the participation of the nervous system on higher animals).

Understanding the graduation Lammark as a gradual increase in the organization of living beings according to the "immutable" laws, essentially leads to the recognition of faith in God. The theory of direct adaptation of organisms to environmental conditions through the appearance of only adequate changes and the mandatory inheritance of the signs purchased by this way logically derives from the presentation of initial feasibility. Inheritance of acquired features was not experimentally confirmed.

To more clearly show the main difference from Lamarc and Darwin in understanding the evolution mechanism, we give an explanation by their own words of the same example.

Education long legs and long neck at the giraffe

By lammark

"It is known that this is the highest mammal animal inhabites in the inner areas of Africa and are found in places where the soil is always dry and deprived of vegetation. It makes Giraf fuss to the foliage of trees and make constant efforts to reach it. As a result of this habit that exists in a long time, all individuals of this breed, the front legs of the giraffes became longer than the rear, and her neck was so long that this is an animal, not even raising on the hind legs, lifting only his head, reaches six meters (about twenty feet) In the height ... Any change acquired by the body due to the usual use sufficient to produce this change, is maintained in the future by reproduction, provided that it is inherent in both individuals together with the participating in fertilization when playing its species. This change is transmitted further and passes, thus, to all individuals of subsequent generations exposed to the same conditions, although the descendants no longer have to acquire it by the way it really was created. "

By Darwin

"Giraffe in its high growth, very long neck, front legs, head and language perfectly adapted to break the leaves from the upper branches of the trees ... The highest individuals, which were inch or two above others, could often persist in periods of drought, wandering in Searches for food throughout the country. This minor size difference caused by the laws of growth and variability does not matter for most species. But otherwise it was with a 10 giraffe hardened 10, if we take into account her likely lifestyle, because those individuals whose or several different parts of the body were longer than usually, in general were to worry. When crossing, they had to leave descendants or with the same characteristics of the structure, or with inclinations to change in the same direction, while the individuals organized less favorably in this regard should be most prone to death. ... Natural selection and protects and thus separates all the higher individuals, giving them a full opportunity to cross, and contributes to the destruction of all lower individuals. "

The theory of direct adaptation of organisms to the environmental conditions through the appearance of adequate changes and their inheritance finds supporters and at present. Open her idealistic character is possible only on the basis of a deep assimilation of Darwin's teachings about the natural selection - the driving force of evolution.

The relativity of the adaptations of organisms. Darwin's teachings about the natural selection not only explained how the fitness could occur in the organic world, but also proved that it always has relative nature. In animals and plants, along with useful signs there are useless and even harmful,

Here are some examples of useless for organisms, inappropriate organs: stale bones at the horse, the remains of the hind limbs in China, the remains of the third century in monkeys and a person, a worm-shaped outflow of a blind intestine in humans.

Any fixture helps organisms to survive only in those conditions in which it has developed natural selection. But in these conditions, it is relative. In a bright, sunny day in winter, white partridge gives himself a shadow on the snow. The hare-white, imperceptible in the snow in the forest, becomes visible against the background of the trunks, fedding on the edge of the forest.

Observations on the manifestation of instincts in animals in some cases show their inappropriate character. Night butterflies fly on fire, although they are dying. They entails an instinct to fire: they collect nectar mainly from bright flowers, well noticeable at night. The best protection of organisms is far from all cases reliable. Sheep eat without harm to themselves the Central Asian Spider-Karakurt, whose bite is poisonous for many animals.

Narrow specialization of the authority may cause the death of the body. Strizh cannot take off with a flat surface, since he has long wings, but very short legs. He takes off, just pushing off some kind of edge, like a springboard.

Fixtures of plants that prevent animal feeding are relative. Hungry cattle eats and spiny protected plants. The mutual benefits of the organisms associated with symbiosis relations are also relative. Sometimes the mushroom filaments of the lichen destroy the coating with them algae. All these and many other facts say that appropriateness is not absolute, but relative.

Experimental evidence of natural selection. Afterwards, Darwinian time was conducted a number of experiments confirmed by the presence of natural selection in nature. For example, fish (gambusia) were placed in swimming pools with different inquired bottoms. The birds destroyed 70% of the fish in the pool, where they were more noticeable, and 43% where they were better approaching the bottom to the bottom.

In another experiment, the behavior of the wretchedman was observed (a detachment of sparrows), which did not slander the caterpillars of the PJSC with a patronage color, until they moved.

Experience confirmed the value of the warning color in the process of natural selection. On the edge of the forest laid on insect boards belonging to 200 species. Birds flew around 2000 times and climbed only those insects that did not have a warning color.

Also experimental means it was found that most birds avoids the interflower insects with an unpleasant taste. By keying the wasp, the bird from three to six months does not touch the obvious flies. Then he begins to peck them until it falls on the wasp, after which the flies do not touch for a long time.

Executed experiences on "artificial mimicry". Birds willingly eaten the larvae of the beetle - a flour wheel stained with tasteless paint carminic. Part of the larvae was covered with a mixture of paint with a quinine or other unpleasant substance. Birds, encroaching on such larvae, stopped pending all the painted larvae. The experience was changed: on the body larvae made various drawings, and the birds took only those whose drawing was not accompanied by an unpleasant taste. Thus, the birds had a conditional reflex for preventing bright signals or pictures.

An experimental study of natural selection was carried out and botany. It turned out that weighing plants possess near biological features, the occurrence and development of which can be explained only as adaptations to the conditions created by human culture. For example, plants Ryzhik (sem. Cruccetic) and Toriza (ses. Cloves) have seeds, very similar largest and weight on flax seeds, whose crops they clog. The same can be said about the seeds of the breedless (sem. Norichnikovy), littering sowing rye. Weighing plants ripen usually simultaneously with cultural plants. Seeds of those and others are difficult to separate from each other when carrying. The man was kicked, threatened the weeds along with the harvest, and then sulled on the field. Involuntarily and unconsciously, he contributed to the natural seed of seeds of various weed plants along the line of similarities with seeds of cultivated plants.

2. Education of new species

For a long time, man struck the diversity of the organic world. How did it occur? The doctrine of natural selection explained how new types of nature are formed. Darwin proceeded from the facts relating to homemade breeds. Initially, the breeds of domestic animals were less diverse compared to modern. Pursuing different goals, people spent an artificial selection in different directions. As a result of breed diversified, i.e. diverged in signs with each other and with their common generic rock .

Divergence in vivo. The divergence occurs all the time in nature, and its driving force is natural selection. The more the descendants of any kind are different from each other, the easier they settle down more numerous and more diverse ranges, the easier it will be multiply. Darwin reasoned in this way. Some kind of predatory four in size has reached the limit of the possibility of existence in this area. Suppose the physical conditions of the country have not changed; Can this predator grow further? Yes, if the descendants will capture places engaged in other animals. And this can occur in connection with the transition to another food or in new conditions of habitat (on trees, in water, etc.). The more diverse the descendants of this predator will be in their signs, the wider they spread.

Darwin gives an example. If there is one species on one piece of land in one of the land, and on the other, similar, are herbs related to several different kinds or childbirth, then in the second case, the overall harvest will be more.

In nature, on the plot, the area is slightly larger than 1 m2 Darwin counted 20 different species Plants belonging to 18 childbirth and 8 families.

Such facts confirm the correctness of the situation put forward by Darwin: "... The largest amount of life is carried out with the greatest diversity of the structure ..." between plants of one species with their identical needs in soil, moisture, lighting, etc. The most fierce biological competition occurs. With natural selection, the forms that are most different from each other will be saved. The more noticeably the differences between the adaptive signs of the forms are, the more the forms themselves are.

Thanks to the natural selection, the evolution process is wearing divergent Character: from one source form originates the whole "fan" of forms, as if special branches from one common root, but not all of them get further development. Under the action of natural selection in an infinitely long row of generations, one forms are saved, others die off; Simultaneously with the process of divergence, the process of extinction is underway, and both are closely related to each other. The most divergent form has the greatest opportunities to survive in the process of natural selection, as they are less competing with each other than intermediate and source, which are gradually radically die and die away.

A variety is a step to form a view. Darwin represented that the formation process of new species in nature begins with the disintegration of the type of intraspecific groups that he called varieties.

Thanks to the natural selection and divergence of varieties, more and more distinguishing their hereditary signs are acquired and become special, new species.

The difference between the species and the species is very large. The varieties of one species are broken between themselves and give a prolific offspring. Types of natural conditions, as a rule, do not cross, due to which biological isolation of species occurs.

To better clarify how the process of speciation in nature is going on, Darwin proposed the following scheme (Fig. 11).

The scheme shows the possible ways of evolution of 11 species of one kind, indicated by letters A, B, C, etc. - to l inclusive. Distances between letters show the proximity between the species.

Thus, the species denoted by letters D and E or F and G are less similar to each other than species A and B or K and L, etc. Horizontal lines mean individual stages in the evolution of these species, and each stage is conditionally adopted for 1000 generations.

Follow the evolution of the species of A. The bundle of dotted lines from the point A portrays its descendants. By virtue of individual variability, they will differ from each other and from the general species A. The useful changes will be saved in the process of natural selection. At the same time, the divergence will detect its useful effect: the signs, the most different (lines A1 and T1 of the beam), will continue, will accumulate from generation to generation and more and more. Over time, systematics recognize A1 and T1 by special varieties.

Let during the first stage - the first thousand years - from the species and there were two clearly pronounced varieties of A1 and T1. Under the influence of conditions that caused the changes in the parent species A, these varieties will be changed further. Maybe at the tenth stage they will have such differences between themselves and with the form A, which should be considered in two separate types: a10 and T10. A part of the species will dy up, and, perhaps, the tenth stage will reach only the F10, forming the third appearance. At the last stage, 8 new species were presented, which began on the form A: A14, Q14, P14, B14, F14, O14, E14 and T14. Types of A14, Q14 and P14 closer to each other than to the rest of the species, and form one genus, the rest-species give two more kinds. The evolution of the form I proceeds in a similar way.

The fate of other species is different: of these, only the species E and F are waiting until the tenth stage, the appearance e then dies. Especially notice the type of F14: it has been preserved to our time almost unchanged compared with the source of F. It can happen if the environmental conditions do not change or change very little for a long time.

Darwin emphasized that in nature, only the most divergent, extreme varieties were not always preserved, the average could also survive and give offspring. One species can overtake another in its development; From extreme species, only one is sometimes developing, but three can develop. It all depends on how endless complex relations Organizes among themselves and with the environment.

Examples of speciation. We give examples of formation of species, and we will use the term subspecies, Adopted in science instead of "variety".

Widely resettled species, such as a bear brown, a hare-beacon, an ordinary fox, an ordinary protein, are found from the Atlantic to the Pacific and have a large number of subspecies. In the middle strip of the USSR, more than 20 types of buttercups grow. They all occurred from one source. The descendants were captured by various habitats - steppes, forests, fields - and due to the divergence gradually made apart from each other first in subspecies, then in species (Fig. 12). Check out other examples on the same picture.

The speciation continues in our time. In the Caucasus lives a coil with a black plumage on the back of the head. For an independent view, it can still be considered, it is a subspecies of ordinary shit. In America, there are 27 subspecies of the singer Sparrow. Most of them externally differ little from each other, but some have sharp differences. Over time, the intermediate by their signs subspecies can extortion, and the extreme will become independent young species, losing the ability to cross each other.

The insulation value. The extensity of the territory of the settlement of the species favors natural selection and divergence. This occurs when the settlement of some kind of locality is resetting. In such cases, the penetration of organisms from one locality to another is very difficult and the possibility of crossing between them is sharply reduced or completely absent.

We give examples. In the Caucasus, there are special subspecies of butterflies, lizards, etc. in the area divided by the highest mountains, etc. in Lake Baikal, many species and childbirth, crustaceans and fish are no longer found. This lake is separated from other water pools. mountain ridges Already about 20 million years and only through the rivers reported with the Northern Arctic Ocean.

In other cases, organisms cannot cross due to biological isolation. For example, two types of sparrow - the house and field - in the winter are held together, but they usually nest differently: the first - under the roofs of the houses, the second - in the wrappers of trees, along the edges of the forest. The form of a black thrush is currently falling into two groups, still indistinguishable externally. But one of them lives in the deaf forests, the other holds near the human housing. This is the beginning of the formation of two subspecies.

Convergence. Mare Existence Animals of various systematic groups sometimes acquire similar to the environment, if they are exposed to the same selecting factor. This process was called convergence - convergence of signs. For example, the front digging limbs of the Crow and the Medveda are very similar, although these animals relate to different classes. It is strongly reminded of each other in the shape of the body of cetaceans and fish, similar limbs in floating animals belonging to different classes. The convergent is both physiological features. The accumulation of fat in the lastonogy and cetaceans is due to the result of natural selection in the conditions of the aquatic environment: reduces the body loss by the body.

Convergence within distant systematic groups (types, classes) is explained only by the action of similar conditions for existence on the course of natural selection. The convergence of relatively nearby animals also affects the unity of their origin, which, as if facilitates the occurrence of similar hereditary changes. That is why it is observed more often within the same class.

Variety of species. Darwin's doctrine on the evolution of the organic world explains the diversity of species as the inevitable result of natural selection and the associated divergence of signs.

Gradually, in the process of evolution, the species became more complicated, the organic world rose to an increasing stage of development. However, animals and plants in nature simultaneously coexist at the same time, with varying degrees of complexity of their organization.

Why didn't the natural selection "raised" all low-organized groups on the highest level of the organization?

Natural selection of all groups of plants and animals is adapted only to their conditions of existence, therefore they could not climb everything on the same high level of the organization. If these conditions did not require an increase in the complexity of the structure, the degree of it did not increase because, according to Darwin, "With very simple life conditions, a high organization would not have any service." In the Indian Ocean, with more or less permanent conditions, the types of challenges of mollusks (nautilus), almost not changed throughout the hundreds of millennia, live. Sometimes to the modern cyzer fish.

Thus, the simultaneous coexistence of organisms of different complexity of the structure is explained by the theory of natural selection and divergence.

The results of natural selection. Natural selection has three closely related essential consequences: 1) gradual complication and improving the organization of living beings; 2) the fitness of the organisms to the conditions of the external environment; 3) species diversity.

Bibliography

1. Azimov A. Short story biology. M., 1997.

2. Kemp P., Arms K. Introduction to biology. M., 2000.

3. Libbert E. General Biology. M., 1978 Lestinate M. History of Physics. M., 2001.

4. Naidysh V.M. Concepts of modern natural science. Tutorial. M., 1999.

5. Needle B. Environmental Science. How the world is arranged. M., 1993.

The emergence of adaptability of organisms.
The main reason for the appearance of various fixtures of living organisms to the habitat is selection. For example, it is known that the partridge is a forest bird. Depending on the habitat, it appears various adaptations: a) shortening the beak in connection with the production of food from under the snow and sheet bedding: b) the appearance of horny folds at the ends of the fingers to facilitate movement in thick snow cover; c) expansion, rounding of wings for rapid lifting into the air (there was no such structure for the ancestors of the partridge).
To further spread the fruits and seeds of plants also underwent various changes. These are hooks, spines, which they attach to animals, or light down, which is scattered by the wind.
The appearance of fitness in plants and animals is a characteristic phenomenon, but in any case, the adaptability does not appear immediately. As a result of a long evolutionary process, individuals appear with special symptoms adapted to the conditions of the external environment.
Features of fitness in the structure, color, body shape and behavior are well visible on the example of aqueous mammal - dolphin. A pointed body shape gives him the opportunity to easily and freely move in water in different directions. Dolphin movement speed reaches 40 km / h. And in the birds, the adaptability indicators for the flight is the presence of feathers covering the body; lack of ear shells and teeth; The ability to rotate the head to 180 "; ease of bones; fast digestion of food in the stomach, etc.
Many animal adaptability is so developed that they are difficult to distinguish them from the environment. The shape of the body, coloring of fish, animals living in thick thickets of algae, help them successfully hide from enemies.

Types of fitness:

1. Pontrery (masking) coloring and its types.
2. Instinctive device.
3. Caring for offspring.
4. Physiological adaptation.

Fig. 21. Fitting of night butterflies by changing the color in the appropriate colors of the tree trunk: 1 - the same number of dark and light butterflies placed; 2 - light tree trunk; 3 - increase the number of light butterflies; 4 - increase the number of dark butterflies; 5 - Dark Tree Barrel

1. Pontrery (masking) coloring and its types. The patronage of color is the fitness of the organisms that live openly and can be available for enemies. Birds, starting eggs on Earth (deaf, partridge, quail, etc.), merge with the surrounding background. The bird sitting on the nest is motionless, almost imperceptible for their enemies. Milotless and eggs that have a pigmented shell and chicks hanging out of them. At large predators, whose eggs are not available for enemies, or in birds, laying eggs high on the rocks or injection them. In the ground, the patronizing color of the shell does not develop. Butterfly caterpillars are usually green, under the color of the leaves, or dark, under the color of the bark. Donate fish (Skat, Kambala) are often painted under the color of sand.
Animals deserts have, as a rule, a sandy yellow color. A monophonic patronage painting is characteristic of insects (locust), lizards, saigas, lions. Depending on the time of year, many animals change coloring. For example, sands, hare-white, swatter in winter have a white color. In daytime butterflies, patronizing coloring on the bottom of the wings, and at night - on the top of the wings, so during the day they become noticeable for enemies and can die (the lower part of the wings is light). The patroness color can be observed in the form of insects: the pupa of butterflies on the branch is very similar to the kidney; The larva attached on the branch in a stationary state is similar to the tree branch, etc.
The patronage of color is especially useful at the initial stages of the individual development of the body (eggs, larva, chick). A patronage color is needed for slowly moving animals or rejoiced at rest.
Many animals are able to quickly change painting depending on the color of the environment, and this ability is inherited. For example: Chameleon, Kambala, Agama.

Types of patronage painting:

1. protective coloring;
2. attracting color;
3. threatening coloring;
4. imprive painting.

1. Protective Warning Color It is characteristic of poisonous, stinging or burning insects. For example, God's cow (red, yellow, brown, dark red, striped) birds are never climbing due to a poisonous, bitter yellowish liquid (Fig. 22). If the chicks randomly smooth this beetle, then the next time they do not fit it. The beetle makes a unpleasant ignition fluid, has a bright red striped color. Coloring bee, bumblebee, wasps, poisonous snakes Protects them from predators. The protective color depends on the behavior of some insects and animals. Sometimes crawling beetles in the moments of danger fade. A stack, nesting in the reeds, accidentally seeing the enemy, pulls the neck, raises up my head and freezes. The warning color in animals is combined with behavior, scareting a predator.

Fig. 22. Warning color: 1 - ladybug; 2 - Faceproof

2. Attracting coloring. This coloring is especially important during reproduction. Bright coloring of red butterflies, blue-haired grasshoppers, tushkars, the plumage of male birds attracts females during the breeding period. In the usual days, the color is merged with the environment and becomes not noticeable for enemies (Fig. 23).

Fig. 23. Attracting Color: 1 - Red Order Tape; 2 - Blue-haired mare; 3 - Tushkhank

3. Threatening coloring. During the danger, animals take a threatening pose. For example, Cobra in the minute danger raises his head straight, inflates the neck and takes a threatening pose; The blackwood beetle raises the abdomen and highlights an unpleasant smell. The eared roundhead instantly reveals the skin folds on the head and freezes with an open mouth. On the disclosed wings of the mantis there are spots similar to the eyes. In case of danger, opening the wings, the mantis scares his enemy. Such stains are also available at night butterflies (Fig. 24).

Fig. 24. Threatening color: Glazchable spots on the wings of the butterfly (1) in the pose of the threat similar to the eyes of the elves (2)

4. Impriveting color - mimicry (Greek Mimikos - "Imitation"). This imitation of animals and plants with living organisms or certain non-living areas of the medium. The warning color of unprotected organisms has similarities with one or several species. For example, on the shape of the body, size, bright coloring the cockroach is similar to God's cow. On the shape of the body of the sea horse and fish-walled reminded algae. White butterfly An unpleasant odor, bright color imitates inedible butterflies from the Heliconide family (Fig. 25), and fly-axes. Similar neyovy Snake With poisonous helps to protect them from enemies and survive.

Fig. 25. Immissory Color: Belyanka Butterfly (T) Looks like a poisonous butterfly-heliconide (2)

Examples of intelligent coloring of plants.
Imatabilities in plants are necessary to attract or intimidating animals. Usually there is no nectar on the whiteness flower. To attract insects, it looks like a honeycomb plant. Insects, sitting on the flower, contribute to his pollination. Flowers insectivorous plants (non-tenta) have a bright color. Insects, sitting on the flower, instantly fall into the "trap" and die. Orchid in the form of a flower and smell resembles a female of some insects, so the males of insects involuntarily sit on the flower and pollinate it.
Mimicry There is a "under the control" of natural selection. The occurrence of it is associated with the accumulation of small useful mutations in edible species in the conditions of their joint habitat with inconsiderable. One of the main tools for protection against enemies and adaptive signs is: bugs and crabs - chitinos, clams - shells, crocodiles - scales, in armaduses and turtles - shell, hedgehog and dickery needles.

Fitness. Protective coloration. Protective coloring. Attracting coloring. Threatening coloring. Impaid painting (mimicry).

1. The main reason for the various devices of organisms to the conditions of the medium is the selection.
2. The patronage of color is the fitness needed to protect organisms leading an open lifestyle, from enemies.
3. Protective coloring is a type of patronage color characteristic of poisonous, stinging, burning insects.
4. Attracting coloring is the type of patronage color during the reproduction of organisms.
5. Threatening painting is a way to protect animals from enemies by making threatening poses.
6. Imitation of living organisms and non-residential areas of the medium is the fitness of organisms that are not capable of independently defending or sedentary.
7. What signs of organisms determine the fitness?
8. How does the fitness arise?
9. Name the types of patronage painting.
10. Show on the example protective coloring.
1. What organisms are peculiar to the resulting color?
2. Give examples proving the usefulness of attracting painting.
3. What are the examples of the imitation color in plants?

The task
Did you meet in the nature of insects that serve when touched? Pay attention to their actions, immobility. Pay attention to insects that allocate an unpleasant odorous smell. Compare them. This task will help you to get more deeply familiar with the protective and threatening painting animals.
Try to task.
What type are the above examples of the patronage color? Enter according to capital letters: "ZSH" - protective; "Pr" - attracting; "PD" is imitative.

1. ladybug. 5. Neventes (insectoral plant).
2. Butterfly. 6. Fill.
3. Beetle-blackwood. 7. Male Pheasant.
4. Sea Horse. 8. Bogomol.

Consider Figures 158-163. What are the adaptations of the organisms depicted in the drawings to habitat? Think whether these devices will continue in organisms if their habitats are changed.

All organisms have a variety of adaptations to habitat. These adaptations develop in the process of evolution in two stages. Initially, new features appear in organisms as a result of mutational and combinative variability. Then these signs are experiencing natural selection on their compliance with environmental conditions.

Examples of devices of organisms. Examples of devices of organisms to the habitat conditions are so numerous that it is almost impossible to describe them. We give only some examples.

Fig. 158. Patronizing color in animals: 1 - solid color of winter plumage in tundra partridge; 2 - Dismeagant coloring in Aksisov deer

Morphological devices include found from different organisms, various types of patronizing, warning painting, disguise and means passive protection.

The patronage of color develops in individuals living openly, which makes them less noticeable on the surrounding background. This color is solid (white plumage color in the tundra partridge in winter), if the surrounding background is homogeneous, or dismembering (light and dark points on the skin of deer-axisov), if the light and shadow stains alternate on the surrounding background (Fig. 158). The effect of the patronage color is enhanced by the corresponding behavior of the animal. At the time of danger, they are hidden, which makes them even less noticeable on the surrounding background.

Warning color develops in individuals having chemicals protection against enemies. These include, for example, sting or poisonous insects, inedible or burning plants. In the process of evolution, they produced not only poisonous chemicals, but also bright, usually red or sewerous colors (Fig. 159). Some animals with the warning color at the moment of danger demonstrate bright stains predator, take a threatening pose than the enemy is confused.

Fig. 159. Warning coloring in frogs-tree

Masking - protection that serves not only in the color, but also a body shape. Distinguish two types of disguise. The first is that the masking organism in its appearance resembles any subject - leaf, bitch, stone, etc. This type of disguise is widely found in insects: ladies, bedbugs and caterpillars of butterflies of the PJs (Fig. 160).

Fig. 160. Masking in Brons-Listhotelok

The second type of disguise is based on the imitative similarity of unprotected organisms with protected. Thus, innocent butterflies-glass insects are reminded by stagnant insects - OS, so the insectivore birds do not touch them (Fig. 161).

Fig. 161. Disguise in butterflies-glass

Means of passive protection increase the likelihood of conservation of the body in the fight for existence. For example, shell's shells, shellfish sinks, enemy needles protect them from attacking enemies. The spikes on the stems of roses and spines in cacti prevent the eating of these plants with herbivore mammals (Fig. 162).

Fig. 162. Means of passive protection in cactus-opsitation

Physiological devices ensure the stability of organisms to change the temperature, humidity, illumination and other conditions of inanimate nature.

So, with a decrease in the ambient air temperature, the level of metabolism decreases in the body and reptiles and winter sleep occurs. In birds and mammals, on the contrary, when the ambient temperature decreases, the metabolism in the body increases, which increases the heat product. Developing a thick feathers, coat and subcutaneous fat layer prevents the heat loss of heat (Fig. 163).

Fig. 163. Winter fur proteins is distinguished by a thick undercoat.

Behavioral devices are found only in animals with highly developed nervous system. They are various forms of behavior aimed at survival of both individual individuals and the species as a whole.

All behavioral devices can be divided into congenital and acquired. It is congenital belonging, for example, the marriage behavior, protection and feeding of offspring, avoiding predators, migration. So, the lioness when climbing his cub remembers their smell. The same process awakens the need to protect lion from enemies (Fig. 164, 1).

Fig. 164. Behavioral adaptations of organisms: 1 - lioness licking lion; 2 - Macasi Japanese, heat in hot source; 3 - Waterfowl Wintering on non-freezing reservoir in the city

Acquired behavioral devices play an important role in animal life. For example, the most northern kind of monkeys - the Japanese Macaque, found in the north of Japan, moved to a snow-water lifestyle (Fig. 164, 2). In winter, with the occurrence of stronger frost, these monkeys are descended from the mountains to hot springs, where they warm in warm water. Another visual example. In large cities middle strip Russia has changed the behavior of migratory birds. So, some waterfowl stopped flying to wintering in warm edges. They are collected in large flocks on non-freezing reservoirs, where there is always the necessary food (Fig. 164, 3).

Relative feasibility of fixtures. All devices in organisms are produced in specific conditions of their habitat. If environmental conditions change, devices can lose their positive valueIn other words, they have relative expediency.

There are many evidence of the relative feasibility of adaptations: the protection of the body from some enemies is ineffective from others; The behavior of the body can become meaningless; Useful in some conditions the organ is useless in others. For example, Kamyshevka, thanks to the parental instinct, feeds the cuckoo, hatched from the egg, swept into the cuckoo nest (Fig. 165).

Fig. 165. Relative feasibility of adaptations of organisms - Kamyshevka, feeding cuckoo

So, the main result of the action of the driving forces of evolution is the appearance of new and improving the existing devices in the organisms. Since the conditions of the existence of organisms change, absolute fixtures in nature do not happen, and the process of their appearance is infinite. In individuals relating to one species, differences in the existing devices are insignificant. The consolidation of these differences in insulation conditions leads to the emergence of new species, i.e. To species.

Exercises on the material passed

1. How do devices occur in individuals to the habitat?
2. What does the relative feasibility of fixtures appear? The answer is illustrated by examples.
3. Can the organisms in the course of long evolution there are absolute, i.e. perfect, fixtures? Answer argue.

Biology knows a lot of cases when a group can be accidentally broken from the main population can form in a few centuries the new kind. Sometimes it even happens that at the same time the individuals of the mother species continue to live on the same territory.

Also, there are also examples when species are forced to dwell in conditions of an ever-changing environment. Often under "change" means constant deterioration of a vital indicator. When leaving the limits of this range, the view most often is simply dying.

Survival backgrounds

Scientists came to the conclusion that the view has a chance of survival only if it becomes actively changing, adapting to sharply changed conditions. This phenomenon is called a phyletic speciation. In this case, not only fitness of organisms to the habitat is formed, but also developing completely new signs for living beings.

Millions of species have been living on our planet. Is it not evidence of the strength of life, her constant variability?! Unfortunately, several millions of years ago, living beings were much more. Some ice periods And the permanent perturbations of the climate led to the fact that the species diversity declined sharply. Survived only the most adapted.

Important examples of adaptations

The brilliant conformity of the living bees and the functions of the centuries that performed by them affected the attention of people: attempts to create gliders with a bird-shaped wing, building ships with rods resembling bodies of marine fish. But much more stronger the perfect, harmonious compliance of the appearance of animals and plants with their natural habitat medium.

Of course, examples can be continued infinitely. Therefore, within the framework of this article, it is possible to tell only about some living beings whose features of the habitat are most clearly and clearly prove the correctness of Darwin.

Birds

So, a person has long been known about the importance of protective coloring for birds, as well as their chicks and eggs in particular. Silence, thermis and partridges (open nesting) egg shell almost perfectly merges with the background of the surrounding terrain. In general, the spin of females is also indistinguishable from the surrounding landscape when looking from the side. The more interesting the fact that the females and eggs of birds, which nest in the wrappers and other hidden places, often have a very bright color (the same parrots, for example).

Insects

And what features of adaptability to habitat have insects? Well, they are still numerous than all representatives of this class. We think that everyone knows the striking similarity of the sticks with dry sprigs. Some studies in this area are still used by the military in the field of building "forest" camouflage costumes.

However, the bodies of many caterpillars are very reminiscent of the sprigs, and the wings of butterflies can pass the leaves of the trees of the terrain where they live. It should be noted here that in this case there is a harmonious combination of the patronage form of the body and the patronizing color. Some butterflies, when they merge with the surrounding terrain, it is difficult to distinguish from the leaves even to the emphasis. If you are more or less known biology, you can finely imagine all the variety of insect class. Finding into the forest or field, you see no more than 2-3% of the total number of them. The rest are simply disguised.

But! It should not be assumed that examples of the adaptability of organisms are limited to banal disguise. Recall the adaptive color when brightly colored, "colorful" insects are not popular with predators, as they are well aware of their sharply negative food qualities. So, the tit or sparrow, trying to eat in your youth a couple of youth, to the end of the life they remember their caustic, poisonous taste.

In addition, the features of the fitness of organisms to the medium include mimicry. This phenomenon resembles a patronage color, but "on the contrary." So, some defenseless and edible species Perfectly can imitate the insects that poisonous or have a disgusting taste. For example, dying flies are very similar to OS, which even many birds are afraid. All this suggests that the fitness of the organisms to the conditions of the medium wears as an adaptive, adaptive character.

Higher mammals

All this can be seen on the example of higher mammals. The zebras color seems to us bright and even somewhat ridiculous, that's just it perfectly repeats the alternation of light and shadows in the thickets of grass, which allows these animals to mask in savannah well. Eyewitnesses confirm that unprepared people sometimes do not notice ZEBR even in an open area, from a distance of only 50-70 m.

Other features

Some living beings have even more amazing and effective adaptation to speech about chameleons and cambal, which can change the color of their body, producing the redistribution of organic pigments in the chromatophores of the skin. Do not forget that the patronage of coloring and other protective factors dramatically improve their effectiveness subject to relevant behavior. Such is the reflex of the fading, the adoption of rest poses, which is characteristic of a huge number of animal species.

Where did the living beings have such an ability?

In general, where did the adaptability of organisms to the habitat appear? In general, in the previous part, we have already expressed the opinion of the Great Darwin: if an animal or plant can survive a sharp change of climate or other conditions, then it is its descendants become the most common. Thus, the main reason for the living beings of some new devices is precisely natural selection. Let's show it in a practical example, discussed the life of a family of auchwine birds that live in the lower flight of the forest.

Features of the structure

Let's remember the main features external structure These birds: the beak is short, it does not interfere with the fodder straight from the forest litter (including with snow cover); On the paws - a thick fringe substrate, with the help of which they can safely walk even in deep snow. Features of the structure of the pen allow them to spend the night, with a head embarrassed in the snow, and short, wide wings make smarters a few of the birds, which are available direct, almost vertical takeoff.

It would be quite logical to assume that their distant ancestors had no such devices in risen. Most likely, after changing a number of some factors of the environment (trite cold), they were forced to adapt to a sharply changed habitat, including cold.

Problem change

New mutations have continuously, there were their diverse combinations when crossed, and the wave number made a population of more heterogeneous and stable. It is not surprising that the birds distinguished from each other a number of signs: someone had frozen on the fingers, some individuals were shortened by beak or wings.

What was the fitness of organisms to the habitat expressed? The fact is that during the constant, only those birds were survived, the parameters of the structure of which most corresponded to the world around. In the process of selection, only they left more offspring, and it was precisely it most often and in an amount sufficient to form a new population. The new generation brought with you new mutations and the whole process was repeated from the very beginning.

Consolidation of useful signs and qualities

Surely among mutations were those that strengthened and secured the manifestation of signs that were previously. Naturally, the birds that these changes appear to have significantly more chances not only to survive, but also to give offspring. Throughout generations, all these signs were accumulated and fixed until those tetherov appeared, which we know now.

Contradictions of Lamarc Theory

As you know, Darwin's theory is radically different from the assumption that was put forward by Jean Baptiste Lamarcom. The latter said that all living organisms could be changed under the influence of the environment, but only in the direction that is extremely useful for them. But it is absurd: What is the impact to contribute to the occurrence of barns at the heroes?

Only the effect of natural selection can explain the occurrence of such a useful device. It is assumed that very distant ancestors of the hedgehog were able to survive, covering an increasingly fracturing hair. Stay alive and the proceedings were obtained by the advantage of those "protests", which were lucky to have the longest and rigid spines.

Other "prickly" examples

At exactly the same way, "bristly hedgehogs" from Madagascar went. We are talking about tenres and few types of crowded mice and hamsters.

Does the fitness of the organisms to the habitat at least some general features? Scientists suggest that the mechanism of occurrence of such devices remains common in all cases: the fact is that they are far from immediately, not at one or two generations. On the contrary, their occurrence is a long and complex process. We should never forget that on the evolutionary path of full dead-up branches and unsuccessful "technical solutions" of nature. We will talk about it now.

Relast adaptability

In the period before Darwin, the adaptation of animals to the habitat served as unanimous evidence of the existence of the Lord and the immense wisdom of the Creator: unless nature could have arranged without such a "leadership" the world So reasonable, balanced way!?

The view reigned that every feature of any living organism is absolutely perfect and exactly corresponds to the task that was assigned to it. So, the trampling helps her to extract nectar even from the most "complex" colors, and the fitness of plants to the habitat in the form of thick cakes and other succulents is ideally adapted for water supply for a long time.

Unfortunately, even many modern scientists continue to relate to nature as a brilliant sculptor, each creation of which is perfect and infallible. But! It is important to clearly realize that this is not so!

A modern study of adaptability to the habitat showed that all changes are always relative, as much slower than the actual change of environmental conditions is formed. Accordingly, many features may be unnecessary, or even directly harmful to the body, if the world has changed.

Proof of relativity

Proof of the fact that the fitness of living organisms is a concept very and very relative, the following examples serve:

• From some enemies, protective devices are very effective, but from other animals they save not particularly well. Snail-cones eat with pleasure, and poisonous shaggy caterpillars includes cuckoo in their diet.
• Not all animal reflexes are really appropriate and adequately correlated with environmental conditions. Remember about the night butterflies that collect pollen from light flowers, well visible at night: they are as hastily fly to the flames of fires and candles, although they are dying.
• The devices that in one environment are really useful in other conditions are harmful and even dangerous. So, who never fall into water in life, there are refill on the paws.
• Bobras, one of the best "engineers" in nature, actively build dams even in standing ponds and pools, which is useless spending forces.

Especially brightly relativity manifests itself in the case of those animals whose homeland is located on the other end GlobeBut which were delivered by a person in a completely new habitat for them. Simply put, exactly the most significant and convincingly proves that nature is far from always infallible.