Presentation on the topic of adaptive features of the structure. Adaptive features of the structure of the body color and behavior of animals, as a result of the action of natural selection. Caring for offspring

Plants and animals are adapted to the environment in which they live. The concept of "fitness of a species" includes not only external signs, but also the correspondence of the structure of internal organs to the functions they perform ( for example, long and complex digestive tract of ruminants that feed on plant foods). The correspondence of the physiological functions of the organism to the conditions of their habitat, their complexity and diversity are also included in the concept of fitness.

There is no doubt about the consistency of the activity of individual parts and systems within the body itself. For a long time, such expediency of the structure served as an argument in favor of the divine origin of wildlife. But Darwin's theory of evolution was able to explain this from a materialistic standpoint. At present, the evolutionary approach to the consideration of biological patterns serves as a natural scientific basis for explaining the expediency of the structure of living organisms and their adaptability to living conditions.

Adaptive features of the structure, body color and behavior of animals

Streamlined body shape- adaptation to overcome the resistance of air (for birds) and water (for aquatic animals) when moving in these environments. This form allows you to develop a high speed of movement and save energy at the same time.

Protective coloration and body shape- the color and shape of the animal's body, contributing to the preservation of its life in the struggle for existence. Protective coloration and body shape are very diverse and are found among many groups of invertebrates and vertebrates. There are 3 types of protective coloration and body shape: disguise , demonstration and mimicry .

Disguise- an adaptation in which the shape of the body and color of the animal merge with the surrounding objects. For example, the caterpillars of some butterflies resemble twigs in body shape and color.

Animals that live in the grass are green in color: lizards, grasshoppers, caterpillars, desert dwellers - yellow or brown: desert locust, round-eared locust, saiga.

Some animals change color during ontogenesis (baby and adult seals), in different seasons of the year ( arctic fox, white hare, squirrel and many others).

Some animals are able to change color in accordance with the background, which is achieved by the redistribution of pigments in the chromatophores of the body integument ( cuttlefish, flounder, agamas and etc.). Camouflage coloring is usually combined with a resting posture.

Disguise contributes to success in the struggle for existence.

Dissecting coloration(disruptive coloration) - coloration with the presence of contrasting stripes or spots that break the contour of the body into separate sections, due to which the animal becomes invisible against the surrounding background.

Dissecting coloration is often combined with imitative surface and background and is found in many animals: giraffe, zebra, chipmunks, in some fish, amphibians, reptiles, from insects - in locusts, many butterflies and their caterpillars.

Concealing coloration is based on the countershading effect: the most brightly illuminated parts of the body are colored darker than the less illuminated ones: in this case, the coloring seems to be more monotonous, and the outlines of the animal merge with the background. This coloration (dark back - light belly) is typical for most fish and other inhabitants of the water column, for many birds and some mammals ( deer, hares).

Warning coloration- a type of patronizing color and shape in which inedible animals have a bright, catchy, sometimes variegated color. These animals are clearly visible in contrasting combinations of colors (black, red, white; orange, white, black, etc.). Many insects have warning coloration, such as soldier bugs, ladybugs, bronzovki, leaf beetles, blisters, various butterflies - minnows, bears and etc.

Among vertebrates, warning coloration is observed in fish, salamanders, toads, toads, and some birds ( drongo), and among mammals - for example, in american skunk. The conspicuousness of animals with warning coloration is their advantage, as they are unrecognizable and are not attacked by predators. Warning coloration contributes to the survival of the species in the struggle for existence and is the result of natural selection.

Mimicry(gr. mimicos- imitative) - imitative similarity of an unprotected organism with a protected or inedible one.

In animals, mimicry promotes survival in the struggle for existence. Mimicry can be not only aimed at passive protection, but also serve as an attack tool, luring prey.

Demonstrative behavioris one of the means of communication in animals. Performing various body movements, for example, birds during the mating season show each other certain areas of plumage, with a bright signal color that carries information.

Demonstrative behavior is used to attract mating partners, in courtship, conflicts with rivals, protecting nests, communicating with chicks, capturing and defending territories, and also as a means of warning of danger.

important for the survival of organisms adaptive behavior. Seasonal animal migrations are an example of adaptive behavior.

seasonal moltassociated with seasonal changes in the living conditions of animals.In animals that do not hibernate, autumn and spring molt is observed annually.

During the autumn molt, the heat-conducting hairline is replaced by thick, warm fur. During the spring molt, simultaneously with the replacement of the cover, in many animals, the upper part of the stratum corneum of the epidermis is desquamated.

Animal feed storage- an important instinct, most developed among the inhabitants of cold and temperate latitudes with sharp seasonal changes in food conditions. It is observed in many invertebrates, in some birds, and especially often in mammals. Of the invertebrates, some spiders, crabs, crayfish and many insects store food.

Of the birds, only wintering ones store food. Most birds use stocks in winter as additional food.

Of the mammals, some predators, pikas and many rodents store food. Stocks are used in winter or spring after waking up from hibernation or winter sleep.

steppe polecat puts gophers in a hole, ermine- water rats, mice, frogs, weasel- small rodents. Many pikas prepare hay by stacking it in piles or in cracks between stones. Squirrel stores mushrooms, nuts and acorns. Chipmunk drags nuts, grains into its hole, a wood mouse - seeds, river beaver- branches and rhizomes, immersing them in water near the entrance to the hole.

Summary of a lesson in biology Grade 9

Topic: "Adaptive features of the structure, body color and behavior of animals"

Target: to get acquainted with different types of adaptability of living organisms to the environment, to understand the relative nature of fitness.

Tasks:

Tutorials:

To form the concept of the mechanisms of the emergence of fitness as a result of evolution;

Continue the development of skills to use knowledge of theoretical laws to explain the phenomena observed in wildlife;

To form specific knowledge about the adaptive features of the structure, body color and behavior of animals, to reveal the relative nature of adaptations

Developing:

Develop interest in the study of biology, broaden your horizons about patterns in nature through situational communication;

To develop the creative abilities of students by independently creating a computer presentation using illustrative material found on the Internet.

develop the intellectual sphere: attention, memory, speech, thinking;

Educational:

to continue the formation of ecological culture among schoolchildren, the belief in the need to preserve the species diversity of plants and animals.

draw conclusions about the natural causes of the formation of adaptations, using the doctrine of the driving forces of evolution;

broaden the horizons of students.

during the classes

1. Actualization of previous knowledge

K.O.Z.

What forces of evolution have we met?

What force of evolution did Charles Darwin consider to be the main one?

Which organisms survive and reproduce as a result of natural selection?

2. Learning new material.

Currently, several million species of living organisms live on our planet, each of which is unique in its own way. Let's find out what is the adaptability of organisms to the environment.

Shared lesson goal setting

During the conversation, we find out the concept of fitness, it appears in the warehouse, the guys write it down in a notebook (the same definition on the information card)

The fitness of organisms, or adaptations (from Latin adaptatio - adaptation, adaptation), are a combination of those features of the structure, physiology and behavior that provide for a given species the possibility of a specific lifestyle in certain environmental conditions.

K.O.Z.

What do you think can be done to adapt to the environment?

In animals, body shape is adaptive. The appearance of the aquatic mammal dolphin is well known. Its movements are light and precise, the speed of movement in water reaches 40 km/h. The density of water is 800 times that of air. How does the dolphin manage to overcome it? The torpedo-shaped streamlined shape of the body, the absence of auricles make it possible to avoid the turbulence of water flows surrounding the dolphin, and reduce friction. A similar body shape in many aquatic animals: sharks, whales, seals. The streamlined shape of the body contributes to the rapid movement of animals in the air. Flight and contour feathers covering the bird's body completely smooth its shape. Birds are deprived of protruding auricles, in flight they usually retract their legs. As a result, birds are far superior in speed to all other animals. Birds move quickly even in water. An Arctic penguin was observed swimming underwater at a speed of 35 km/h.

Organismal adaptations - entry in a notebook.

K.O.Z. Even Ch. Darwin emphasized that all adaptations, no matter how perfect they are, are relative in nature, i.e. useful only in a typical habitat.

For example, a woodpecker easily moves along tree trunks, but its limbs are poorly adapted to move along the soil surface.

Waterfowl do not move well on land.

K.O.Z.

Let's remember such a force of evolution as the struggle for existence. What forms of struggle for existence do you know?

What is the peculiarity of the interspecies struggle for existence, between whom does it take place?

how should predators and their prey adapt?

SLIDES No.

students write down definitions, draw conclusions about the relative nature of any adaptation.

protective coloration

solid

broken

change in body color

warning coloration

However, often in animals there is a body color that does not hide, but, on the contrary, attracts attention, unmasks. This form of adaptation is called warning coloring. It is characteristic of most stinging, poisonous, disgusting-smelling or disgusting-tasting animals. Like stoplights, these patterns and color combinations should be easily recognized by the animals. They mean: "Dangerous!", "Don't come near!", "It's better not to mess with me!". A ladybug, very noticeable, is never pecked by birds because of the poisonous secret secreted by insects. Inedible caterpillars, many poisonous snakes have a bright warning color. Among amphibians there are real dandies. They are spectacularly coloured, often slow, diurnal, and do not even try to hide from predators, unlike their more numerous camouflaged relatives, who go in search of food at night, when they are less visible. The most peculiar among amphibian dandies are, perhaps, poison dart frogs, inhabitants of Central and South America. Their skin glands produce powerful paralyzing poisons, so that a predator that has tried to eat such a frog and survived, associates the experienced unpleasant moments with its bright colors and in the future diligently avoids its like. Among the approximately one hundred thousand species that make up the order of Lepidoptera, or butterflies, bears belong not only to the most familiar, but also to the most beautiful. She has an extremely effective warning coloration - orange-black and yellow-black with patterns of spots and stripes. The bear is very pretty, but poisonous. Special glands produce strong toxins that enter the butterfly's bloodstream. Other glands contain a liquid with an unpleasant warning odor. In the tropical coastal waters of Australia, New Guinea, Indonesia and the Philippines, a small (up to 20 cm long with tentacles) blue-ringed octopus lives. Bright orange round spots are bordered by characteristic blue rings. Like all representatives of the genus, the blue-ringed octopus has an amazing ability to regenerate, and, having lost one or more of its eight tentacles in battle, it can quickly grow new ones. As beautiful as this octopus is, it is also poisonous. Animal saliva contains the strongest neurotoxin. The bite of the blue-ringed octopus is deadly. The poison almost instantly paralyzes the nervous system of any living creature, and there is no antidote for it.

mimicry

The effectiveness of warning coloring was the cause of a very interesting phenomenon - imitation, or mimicry. Mimicry is the imitation of a less protected organism of one species to a more protected organism of another species. This imitation can manifest itself in body shape, coloration, and so on. Covered with warning stripes, but completely harmless, the hoverfly fly extracts nectar from the flower, as do honey bees, which have a formidable sting. Hoverfly mimicry is not limited to coloration, but includes behavior as well. Hoverflies imitate the sounds made by bees and wasps and, if disturbed, buzz menacingly. All this together guarantees immunity to the hoverfly. The beautiful butterfly danaid owes its inedibility to the fact that its caterpillars feed on the leaves of poisonous lettuce, which is dangerous for livestock and other vertebrates. Winged predators quickly learned not to touch the danaids, and at the same time their imitator, one of the nymphalids - only slightly tasteless. The glass butterfly is surprisingly similar to a wasp. Its wings are completely transparent, since it does not have scales covering the wings of butterflies. When flying, it buzzes like wasps, and flies as swiftly and restlessly as they do. Already imitates the color of the viper, it is given out only by yellow spots on the head. Many imitators have acquired venomous coral snakes. For example, the Arizona king snake, which is not venomous.

disguise

In animals leading a hidden, hiding way of life, adaptations are useful that give them a resemblance to environmental objects - disguise. For example, moth butterfly caterpillars resemble knots in body shape and color. Stick insects look like a small brown or green twig, some butterflies look like dried leaves, and spiders look like thorns. The great masters of disguise owe much of their success to their ability to freeze at the moment when they are threatened with an attack or they themselves are preparing to seize the prey. Among animals, those who in one way or another imitate flowers are especially diverse. For example, flower praying mantises are so similar to one or another part of the plant that other insects, deceived by the similarity, descend directly on them and fall into the arms of a predator.

Students write definitions and draw conclusions about the relative nature of any adaptation..

K.O.Z. How do such perfect adaptations come about?

The clue lies in the complex process of natural selection. For example, the distant ancestor of a butterfly, now almost indistinguishable from a dry leaf, was born with a random set of genes that made it look a little more like a dry leaf. Therefore, it was somewhat more difficult for the birds to find this butterfly among the dry leaves, and as a result, she and her like individuals survived in greater numbers. Consequently, they left more offspring. And the sign of “dry leaf” became more and more clear and common. All traits are the result of mutations. One large mutation can occur, or a huge number of small ones, which happens much more often. Those that increase vitality are passed on to subsequent generations, fixed and become adaptations. Each adaptation is developed on the basis of hereditary variability in the process of struggle for existence and selection in a number of generations.

What conclusions can be drawn from all of the above?

1. The general adaptability of organisms to environmental conditions consists of many individual adaptations of very different scales.

2. All adaptations arise in the course of evolution as a result of natural selection.

3.Any fit is relative.

Thus, fitness is the relative expediency of the structure and functions of an organism, which is the result of natural selection.

In the process of evolution, animals have developed various physiological and behavioral mechanisms that allow them to better adapt to the environment. What adaptive features of the structure, color and behavior of animals exist? What do they depend on?

Adaptive behavior of animals

Behavior refers to actions aimed at interacting with the outside world. It is characteristic of all animal beings and is one of the main tools of adaptation. The principles of animal behavior can change under the influence of external and internal factors.

For the existence of organisms, all environmental factors are important - climate, soil, light, etc. Changes in at least one of them can affect their way of life. The adaptive features of animal behavior help them adapt to new conditions, which means they increase the chances of survival.

Even elementary forms of life are capable of responding to environmental stimuli. The simplest, for example, can move around to reduce the negative impact of any factor. In highly organized organisms, behavior is more complex.

They are able not only to perceive information, but also to remember and process it in order to use it in the future for self-preservation. These mechanisms are controlled by the nervous system. Some actions are inherent in animals from the very beginning, others are acquired in the process of learning and adaptation.

reproductive behavior

The reproduction of offspring is inherent in the nature of every living organism. Adaptive behavior is manifested during sexual reproduction, when animals need to find a partner, form a pair with him. With asexual reproduction, this need does not arise. Courtship is highly developed in higher organisms.

To win a partner, animals perform ritual dances, make various sounds, for example, screams, trills, singing. Such actions give the opposite sex a signal that the individual is ready for mating. Deer during the mating season emit a special roar, and when they meet with a potential rival, they arrange a fight. Whales touch each other with their fins, elephants stroke their trunks.

Adaptive behavior is also manifested in parental care, which increases the chances of young individuals for survival. It is mainly characteristic of vertebrates and consists in building a nest, incubating eggs, feeding and learning. Monogamy and strong pairings predominate in species where the young require long-term care.

Food

Adaptive behavior associated with nutrition depends on the biological characteristics of the animal. Hunting is common. It is carried out with the help of surveillance (in squids), traps (in spiders) or simple waiting (in praying mantises).

To save effort and time, some species use theft. For example, cuckoo bees do not build their own hives, but boldly penetrate into strangers. They kill the queen, lay their larvae in the colony, which are fed by unsuspecting worker bees.

Coyotes have adapted by being omnivores. So they significantly expanded their habitat. They can live in desert, mountainous areas, even adapted to life near cities. Coyotes eat anything, up to carrion.

One way to adapt is to store food. Insects stock up to feed the larvae. For many rodents, this is part of the preparation for the bad season. Hamsters store about 15 kilograms of food for the winter.

Protection

Various defensive reactions of animals protect them from enemies. Adaptive behavior in this case can be expressed passively or actively. A passive reaction is manifested by hiding or fleeing. Some animals choose different tactics. They may pretend to be dead or freeze motionless in place.

Hares run away from danger, while confusing their tracks. Hedgehogs prefer to curl up in a ball, the turtle hides under the shell, the snail - in the shell. Species living in flocks or herds try to snuggle closer to each other. This makes it more difficult for a predator to attack an individual, and it is likely that he will abandon his intention.

Active behavior is characterized by a vivid demonstration of aggression to the enemy. A certain posture, the position of the ears, tail and other parts should warn that the individual should not be approached. For example, cats and dogs show fangs, hiss or growl at enemies.

public behavior

When animals interact with each other, adaptive behavior differs in different species. It depends on the characteristics of development and the way of life of an individual and is aimed at creating favorable living conditions and facilitating existence.

Ants team up to build anthills, beavers to build dams. Bees form hives, where each individual performs its role. Penguin cubs unite in groups and are under the supervision of adults while their parents hunt. Cohabitation of many species provides them with protection from predators and group defense in case of attack.

This includes territorial behavior, when animals mark their own possessions. Bears scratch the bark of trees, rub against them or leave tufts of wool. Birds give sound signals, some animals use smells.

Structural features

Climate has a strong influence on the adaptive features of the structure and behavior of animals. Depending on the degree of air humidity, the density of the environment, temperature fluctuations, they historically formed different body shapes. For example, underwater inhabitants have a streamlined shape. It helps you move faster and maneuver better.

A characteristic structure for living conditions is the size of the ears of foxes. The colder the climate, the smaller the ears. In foxes living in the tundra, they are small, but in the fennec fox living in the desert, the ears reach up to 15 cm in length. Large ears help the fennec fox to cool off in the heat, as well as to catch the slightest movement.

Desert dwellers have nowhere to hide from the enemy, so some have good eyesight and hearing, others have strong hind limbs for fast movement and jumping (ostriches, kangaroos, jerboas). Their speed also saves them from contact with hot sand.

Northerners may be slower. The main adaptations for them are a large amount of fat (up to 25% of the total body in seals), as well as the presence of hair.

Color features

An important role is played by the color of the body and coat of the animal. Thermoregulation depends on it. Light color allows you to avoid exposure to direct sunlight and prevent overheating of the body.

Adaptive features of body color and behavior of animals are closely related to each other. During the mating season, the bright color of males attracts females. Individuals with the best pattern receive the right to mate. Newts have colored spots, peacocks have multi-colored feathers.

Color provides protection to animals. Most species camouflage themselves in the environment. Poisonous species, on the contrary, can have bright and defiant colors that warn of danger. Some animals in color and pattern only imitate poisonous counterparts.

Conclusion

Adaptive features of the structure, color and behavior of animals in many ways Differences in appearance and lifestyle are sometimes noticeable even within the same species. The main factor for the formation of difference was the environment.

Each organism is maximally adapted for living within its range. In the case when conditions change, the type of behavior, color and even the structure of the body may change.

Question 1. Give examples of the adaptability of organisms to the conditions of existence based on your own observations.

In the course of evolution, organisms acquire various properties that allow them to more successfully adapt to living conditions. For example, the fur of northern animals (arctic foxes, bears) is white, making them almost invisible against the background of snow. Insects that feed on flower nectar have a proboscis structure and length that is ideal for this. The seal flippers, modified from the paws of their land ancestors, are perfectly adapted to movement in the water. Giraffes live in the savannah and eat the leaves of trees at high altitudes, with the help of their long necks.

There are many such examples, since each living creature has a large number of features acquired in the process of adapting to specific living conditions.

Question 2. Why do some animals have a bright, unmasking color, while others, on the contrary, have a protective one?

Two types of coloring correspond to two variants of the strategy of behavior. In one of them, the animal tends to go unnoticed, trying to avoid a meeting with a predator or sneaking up on a prey. For this, a protective coloration is used to blend in with the background. On the other hand, animals that are dangerous or poisonous often emphasize this in every possible way. They use bright, unmasking coloration, warning "don't eat me." In addition to poisonous organisms, this strategy is used by harmless species mimicking for them. Organisms can have unmasking coloration for a completely different reason - in connection with the desire to attract a partner for reproduction (the bright color of many male birds, fish, reptiles, butterflies, etc.). In this case, the task of procreation comes into conflict with the instinct of self-preservation, but it turns out to be more significant for the organism.

Question 3. What is the essence of mimicry? Compare mimicry and disguise. What are their fundamental differences? How are they similar?

The essence of mimicry (from the Greek mimikos - imitative) lies in the fact that harmless animals in the process of evolution become similar to dangerous (poisonous) species. This allows them to avoid predation. Some non-venomous snakes serve as an example: there is a species of snake that is similar in color to the deadly asp and differs from it only in the alternation of stripes. In addition to color, mimic animals have a characteristic behavior: hoverfly flies behave like wasps, imitating aggression.

Question 4. Does the action of natural selection extend to the behavior of animals? Give examples.

Natural selection affects not only the external signs of the organism, but also behavior. This applies, first of all, to innate (instinctive) forms of behavior. Such forms are very diverse: ways of obtaining food, manifestations of fear and aggression, sexual behavior, parental behavior, etc. The spider weaves a web, the bee builds honeycombs, the cat assumes a threatening posture at the moment of danger, chipmunks stock up and hibernate for the winter and etc. Very complex mating rituals, strict adherence to which is for animals one of the ways to prevent interspecific crossing.

Question 5. What are the biological mechanisms for the emergence of adaptive (concealing and warning) coloration in animals?

The biological mechanism that ensures the emergence of adaptive coloration is natural selection. In the process of evolution, in a population that, due to the diversity of the gene pool, was distinguished by a very wide range of colors, those individuals that were less noticeable against the background of the environment mainly survived and left offspring. As a result, the proportion of corresponding genotypes has steadily increased. Subsequently, this phenotype, and hence the genotype, was fixed in the population with the help of stabilizing selection. In the case of warning coloration, similar processes occurred. For example, birds initially find and eat bright insects more easily. If these insects turn out to be poisonous, then birds quickly learn not to touch them and prefer more modestly colored prey. Thus, individuals with a bright color, which is easy to identify as poisonous, are preserved and leave offspring. Over time, this trait is fixed in the population.

Question 6. Are there living organisms that do not have adaptive structural features? Justify the answer.

Adaptation is a set of features of the structure, physiology and behavior of living organisms to specific conditions in which they can normally exist and leave offspring.

The emergence of adaptability to the environment is the main result of evolution. Therefore, evolution can be seen as a process of adaptations or adaptations.

Organisms that failed to adapt to the environment died out.

Summary of a lesson in biology Grade 9

Topic: "Adaptive features of the structure, body color and behavior of animals"

Textbook: "Biology General Patterns Grade 9" S.G. Mamontov, V.B. Zakharov, N.I. Sonin

biology teacher MBOU secondary school No. 37 Lukyanenko A.S.

Target: to get acquainted with different types of adaptability of living organisms to the environment, to understand the relative nature of fitness.

Tasks:

to continue the formation of ecological culture among schoolchildren, the belief in the need to preserve the species diversity of plants and animals. draw conclusions about the natural causes of the formation of adaptations, using the doctrine of the driving forces of evolution; broaden the horizons of students.

№ lesson

during the classes

1. Actualization of previous knowledge

K.O.Z.

What forces of evolution have we met?

What force of evolution did Charles Darwin consider to be the main one?

Which organisms survive and reproduce as a result of natural selection?

What do you think can be done to adapt to the environment?

K.O.Z.

Let's remember such a force of evolution as the struggle for existence. What forms of struggle for existence do you know? What is the peculiarity of the interspecies struggle for existence, between whom does it take place? how should predators and their prey adapt?

solid broken

SLIDE #13-14warning coloration However, often in animals there is a body color that does not hide, but, on the contrary, attracts attention, unmasks. This form of adaptation is called warning coloring. It is characteristic of most stinging, poisonous, disgusting-smelling or disgusting-tasting animals. Like stoplights, these patterns and color combinations should be easily recognized by the animals. They mean: "Dangerous!", "Don't come near!", "It's better not to mess with me!". A ladybug, very noticeable, is never pecked by birds because of the poisonous secret secreted by insects. Inedible caterpillars, many poisonous snakes have a bright warning color. Among amphibians there are real dandies. They are spectacularly coloured, often slow, diurnal, and do not even try to hide from predators, unlike their more numerous camouflaged relatives, who go in search of food at night, when they are less visible. The most peculiar among amphibian dandies are, perhaps, poison dart frogs, inhabitants of Central and South America. Their skin glands produce powerful paralyzing poisons, so that a predator that has tried to eat such a frog and survived, associates the experienced unpleasant moments with its bright colors and in the future diligently avoids its like. Among the approximately one hundred thousand species that make up the order of Lepidoptera, or butterflies, bears belong not only to the most familiar, but also to the most beautiful. She has an extremely effective warning coloration - orange-black and yellow-black with patterns of spots and stripes. The bear is very pretty, but poisonous. Special glands produce strong toxins that enter the butterfly's bloodstream. Other glands contain a liquid with an unpleasant warning odor. In the tropical coastal waters of Australia, New Guinea, Indonesia and the Philippines, a small (up to 20 cm long with tentacles) blue-ringed octopus lives. Bright orange round spots are bordered by characteristic blue rings. Like all representatives of the genus, the blue-ringed octopus has an amazing ability to regenerate, and, having lost one or more of its eight tentacles in battle, it can quickly grow new ones. As beautiful as this octopus is, it is also poisonous. Animal saliva contains the strongest neurotoxin. The bite of the blue-ringed octopus is deadly. The poison almost instantly paralyzes the nervous system of any living creature, and there is no antidote for it.SLIDE No.mimicry The effectiveness of warning coloring was the cause of a very interesting phenomenon - imitation, or mimicry. Mimicry is the imitation of a less protected organism of one species to a more protected organism of another species. This imitation can manifest itself in body shape, coloration, and so on. Covered with warning stripes, but completely harmless, the hoverfly fly extracts nectar from the flower, as do honey bees, which have a formidable sting. Hoverfly mimicry is not limited to coloration, but includes behavior as well. Hoverflies imitate the sounds made by bees and wasps and, if disturbed, buzz menacingly. All this together guarantees immunity to the hoverfly. The beautiful butterfly danaid owes its inedibility to the fact that its caterpillars feed on the leaves of poisonous lettuce, which is dangerous for livestock and other vertebrates. Winged predators quickly learned not to touch the danaids, and at the same time their imitator, one of the nymphalids - only slightly tasteless. The glass butterfly is surprisingly similar to a wasp. Its wings are completely transparent, since it does not have scales covering the wings of butterflies. When flying, it buzzes like wasps, and flies as swiftly and restlessly as they do. Already imitates the color of the viper, it is given out only by yellow spots on the head. Many imitators have acquired venomous coral snakes. For example, the Arizona king snake, which is not venomous.SLIDE No. disguise In animals leading a hidden, hiding way of life, adaptations are useful that give them a resemblance to environmental objects - disguise. For example, moth butterfly caterpillars resemble knots in body shape and color. Stick insects look like a small brown or green twig, some butterflies look like dried leaves, and spiders look like thorns. The great masters of disguise owe much of their success to their ability to freeze at the moment when they are threatened with an attack or they themselves are preparing to seize the prey. Among animals, those who in one way or another imitate flowers are especially diverse. For example, flower praying mantises are so similar to one or another part of the plant that other insects, deceived by the similarity, descend directly on them and fall into the arms of a predator.Students write definitions and draw conclusions about the relative nature of any adaptation..

K.O.Z. How do such perfect adaptations come about? The clue lies in the complex process of natural selection. For example, the distant ancestor of a butterfly, now almost indistinguishable from a dry leaf, was born with a random set of genes that made it look a little more like a dry leaf. Therefore, it was somewhat more difficult for the birds to find this butterfly among the dry leaves, and as a result, she and her like individuals survived in greater numbers. Consequently, they left more offspring. And the sign of “dry leaf” became more and more clear and common. All traits are the result of mutations. One large mutation can occur, or a huge number of small ones, which happens much more often. Those that increase vitality are passed on to subsequent generations, fixed and become adaptations. Each adaptation is developed on the basis of hereditary variability in the process of struggle for existence and selection in a number of generations.

What conclusions can be drawn from all of the above?

1. The general adaptability of organisms to environmental conditions consists of many individual adaptations of very different scales.2. All adaptations arise in the course of evolution as a result of natural selection.3.Any fit is relative.Thus, fitness is the relative expediency of the structure and functions of an organism, which is the result of natural selection.

Reflection D.Z.