Interesting facts about amphibians. Class amphibians: the rarest and strangest representatives

What do we know about amphibians? When witches brewed their potion hundreds of years ago, traditionally toads have always been a key ingredient in any witchcraft potion. The strong poison of some amphibians, for example, has long been used as a weapon, with which the Choco Indians lubricated the tips of their arrows.

Toads and frogs are a traditional symbol of ugliness, rejection and rejection. In 16th century England, a woman in whose house a toad was found was tried for witchcraft. But why a toad? Because of their skin, the shape of the body, or it still contains dark forces? Since ancient times, there have been many stories about stones that suddenly split open, releasing the toad that lived inside. Witchcraft, magic? No. it hibernation. In order not to freeze in winter, toads fall asleep in dark and warm places.

The skin of amphibians can also serve as medicine. In 1986, in the secretion of the African clawed frog, new class antibiotics. More recently, scientists have found that frog skin contains an anesthetic that is 200 times stronger than morphine. holes in ozone layer made amphibians unwitting sensors of the planet's health. Ultra-violet rays that cause cancer in humans are also detrimental to them.

Scientists believe that amphibians at an accelerated pace reflect the course of evolution, during which Homo sapiens appeared. The tadpole loses its gills immediately after birth and begins to breathe with lungs. At the sixth week of life, his hind limbs grow back. Nine weeks later, the tadpole looks like a frog. There are lungs that swallow air from the surface of the water, and forelimbs. Each hour of his life corresponds to a million years of evolution.

The tadpole loses its gills immediately after birth and begins to breathe with lungs. At the sixth week of life, his hind limbs grow back. Nine weeks later, the tadpole looks like a frog. There are lungs that swallow air from the surface of the water, and forelimbs. Each hour of his life corresponds to a million years of evolution.

Over time, the tadpole develops vision and hearing. Tailless amphibians hear perfectly - this is a proven fact. Males attract females by singing. The cry consists of two tones. But females hear only a high sound - inviting, and other males, only a low - threatening. For American males, good hearing is very important. They are aggressive and constantly listen for nearby rivals. Their ears are almost twice the size of their eyes.

The vision of amphibians depends on the habitat. Eyes are also different types, differ in shape and size. Narrow, cat-like pupils, either horizontal or vertical, make it possible to see in the dark. The pupils of amphibians are square, even heart-shaped. The colors of their eyes are also striking in their diversity, there are even red ones, for example,

Amphibians are animals that live both in water and on land. These include frogs, toads, newts and salamanders. Amphibians lay their eggs in water, such as a pond or stream. They cannot live in salt water, so they are not in the seas. Newts and salamanders are amphibians. Unlike frogs and toads, they do not lose their tail when they grow up. Tritons are more attached to water than other amphibians. These are almost entirely aquatic animals.

Not quite lizards

Newts and salamanders look like lizards, but they are not reptiles, but amphibians. Their life begins and usually almost all passes in the water. Tritons live in temperate climate, in winter they crawl under logs and stones and hibernate. Salamanders live in warmer climates and do not need hibernation.

The largest salamander

The giant salamander is the largest amphibian animal, its length is up to 1.8 m.

Tritons are handsome

In many newts, the males are very beautiful. They become especially bright and beautiful in the mating season, when you need to attract the attention of females. The crested newt has a bright orange or yellow belly, and a large uneven crest runs along the entire back. Three species of newts live in Russia - common, crested and Asia Minor.

Caring for offspring

The female newt protects the eggs from predators by hiding them or wrapping them in the leaves of aquatic plants.

Fire salamander.

Fire salamanders got their name from the fact that they usually hide under logs, and they have to quickly jump out of the fire if they accidentally get there with firewood.

Frogs and toads

Poison frogs - poison dart frogs live in the Amazon forests. Their skin releases a poison that is deadly to animals and humans. The bright color of the frog warns that it is poisonous. The Indians used frogs to make poison arrows.

tree frogs rainforest live far from water bodies, but they still prefer wet places.

Skin breathing. Most frogs breathe not only with their lungs, but also with their skin, so their skin must be kept moist at all times. Frogs are excellent swimmers and usually live near water, except for tree frogs.

Frogs - jumpers

The powerful hind legs of the frog help it to jump far and high. Toads usually do not jump, but walk. Adult frogs and toads do not have tails.

The largest and smallest frog.

The most big frog- This is a goliath frog from West Africa. It weighs up to 3 kg, and the length of the elongated frog is almost 80 cm. The smallest frog lives in Brazil. Its length is only 8.5 mm.

flying frogs

Some tree frogs can glide in the air. On the fingers of their paws they have suction cups, and between the fingers they have membranes that work like spread wings.

toads

Generally, toads have drier skin than frogs. The skin of toads is covered with warts and can be poisonous. The hind legs of toads are shorter than those of a frog, and the toad usually walks rather than hops. Toads are usually less mobile than frogs.

In my dad's mouth. The male Darwin frog from Chile carries the eggs laid by the female in its mouth until the tadpoles hatch.

Amphibians

Amphibians, or amphibians, usually spend part of their lives in water and part on land. The very name "amphibian" means "living a double life." Amphibians were the first vertebrates to migrate from water to land almost 400 million years ago. More than 4500 species of amphibians are now known. Amphibians include frogs, toads, newts, salamanders. Most often, amphibian babies hatch in water from eggs. At first, they look like fish fry, but soon their paws grow and lungs appear for breathing air. A little more - and the animals are ready to land on land, where they usually spend almost all adulthood. But amphibians do not go far from the water and always return to the water to lay their eggs (caviar).

The sounds made by the barking tree frog, as its name implies, is the barking of a dog, and with a variety of variations, consisting of about a dozen sounds. Both male and female amphibians of this species bark. Frog "barking" is born in the throat pouches. Usually imperceptible, when "singing" these bags inflate almost to the size of the frog itself.

Frog - bull

Frog - bull, lives in North America, reaches a length of twenty centimeters and weighs about seven hundred grams. These frogs are real predators: they feed on invertebrates, small fish and frogs, and sometimes even chicks. waterfowl. Males, especially in mating season, make loud, bull-like sounds that carry around for a mile or more. Gourmets appreciate the most tender meat of the hind legs of a frog - a bull, a pair of which weighs almost four hundred grams. In the US, these large amphibians are bred on several farms.

Studying amphibians, scientists discovered they have remarkable navigational abilities, the ability to navigate by the sun, moon and stars. A noisy frog lives in North America (an adult reaches a length of seven centimeters), which, if it finds itself in an unfamiliar place, orienting itself on the ground and choosing for short term the right direction, sets off on a journey and unmistakably finds its place of dwelling.

As you know, the body of tailless amphibians is covered with bare, unprotected skin. However, in 1900 in Gabon ( Central Africa) hairy frogs have been found. As a result of their study, it became clear that the “wool” of frogs is only additional outgrowths of the skin that produce mucus, with the help of which the body retains moisture, which is especially necessary for amphibian species that live in hot climates.

Frogs - females make sounds if they get hurt, but loud croaking is heard at night - songs exclusively of males. The main purpose of their concerts is to attract the attention of females during the mating season. But even after this period they perform their guttural songs.

Red-eyed tree frog, the length of its body reaches seven centimeters from the genus Phyllomedusa, settles near water bodies, mainly in forests. These amphibians are diurnal. They look with unusual red eyes, the lower eyelids of which are covered with a mesh pattern. With impending danger, these emerald-colored beauties close their eyes and turn invisible against the background of bright green foliage, for which they are often called ghost frogs. The red-eyed tree frog is the owner of tenacious paws, the first finger of which is opposed to the rest, for which it allows it to deftly grab onto tree branches. Larger than the male, the female, having put the partner she likes on her back, climbs, like a real climber, with him on a tree, to a height of up to seven meters. They move on smooth surfaces with the help of special suction cups that are on their fingers. The sticky liquid secreted from the fingertips, as well as from special glands in the throat and abdomen, allows tree frogs to better hold on to the surface.

Blue poison dart frog (its body length is about four centimeters) can only be found in South Suriname, in forests near streams. Dark sapphire in low light, in bright light it literally phosphorescent. Meanwhile, this dandy of amazingly beautiful color is far from harmless. The skin of the rare blue poison dart frog produces a very strong poison, which makes it extremely dangerous for large animals and humans.

The coloring poison dart frog, about four centimeters in size, lives in the Central and South America, from Nicaragua and Costa Rica to Southeast Brazil and Bolivia. He usually settles in the lower tier wet forest, in old trees with small hollows and crevices at the base of the trunk. These amphibians secrete a special mucus, which you smear, for example, on the skin of parrot chicks, and instead of green feathers, they will grow red. Interestingly, the mucus also contains epibatidine, a powerful pain reliever. It is two hundred times more effective than morphine and does not cause negative side effects.

Tree frog - cocked hat, body length of almost ten centimeters, an extremely rare frog of the family of marsupial tree frogs - lives in South America. Protective coloration makes it look like a piece of tree or lichen bark, so this frog becomes completely invisible against the background of trees and stones. Taking care of the offspring, the female carries the fertilized eggs in a special leather pocket, which is located on her back.

It is frogs that produce the strongest poisons in nature. The record holder for "poisonousness" is the Colombian leaf frog ukoki. The poison of this crumb in toxicity, many times greater than that of a snake, retains its strength for several years. The Indians rubbed their arrowheads with it, one frog was enough to make fifty poisoned arrows. Once in the blood, ukoki poison kills a person in a few minutes. the same substances also have bactericidal properties, thanks to which frogs destroy harmful microorganisms that fall on their skin. In the old days, frogs were placed in containers with milk so that it would not turn sour: their poisonous mixture inhibited the growth of lactic acid bacteria, and the milk remained fresh.

Despite the fact that amphibians are distributed throughout the Earth, this is one of the few classes of animals that is practically not used by humans. Unless in the tropics (and in one of European countries, whose inhabitants are called “frogs” for their addiction to frog legs), some types of amphibians are eaten, and biologists like to experiment on amphibians. Basically, amphibians and humans live on their own and rarely intersect.

A person's lack of mercantile interest in them does not make amphibians boring. Amphibians have their own characteristics, some of them are very interesting. In the selection below - teeth that are not chewed, a frog like a refrigerator, freezing newts, fireproof salamanders and other interesting facts.

1. All amphibians are predators. Even their larvae eat plant foods only at a young age, and then switch to live food. Of course, this is not from some kind of innate bloodthirstiness, it does not happen in nature. In the body of amphibians, the metabolism is very sluggish, so they can only survive on high-calorie animal food. Do not shun amphibians and cannibalism.

2. The teeth that some amphibians have are not designed for chewing prey. This is a tool for catching and capturing it. Amphibians swallow their food whole.

3. Absolutely all amphibians are cold-blooded. Therefore, the temperature environment plays decisive role for their survival.

4. The life of amphibians begins in the water, but most of it takes place on land. There are amphibians that live exclusively in aquatic environment, but there are no reverse exceptions, there are only species that live only on trees in the humid jungle. So "amphibians" is a surprisingly accurate name.

5. However, even when most time on land, amphibians are forced to constantly return to the water. Their skin is permeable to water, and if it is not moistened, the animal will die of dehydration. On their own, amphibians can secrete mucus to moisten their skin, but the resources of their organisms, of course, are not unlimited.

6. The permeability of the skin, which makes amphibians so vulnerable, helps them breathe normally. They have very weak lungs, so some of the necessary air is drawn into the body through the skin.

7. The number of amphibian species does not even reach 8 thousand (more precisely, there are about 7,700 of them), which is quite a bit for a whole class of living beings. At the same time, amphibians are very sensitive to the environment and do not adapt well to its changes. Therefore, environmentalists believe that up to a third of amphibian species are under threat of extinction.

8. Amphibians are the only class of creatures living on land whose offspring in their development passes through a special stage - metamorphosis. That is, not a reduced copy of an adult creature appears from a larva, but another organism, which subsequently turns into an adult. For example, tadpoles are frogs in the stage of metamorphosis. In the development of more complex organisms, there is no stage of metamorphosis.

9. Amphibians come from lobe-finned fish. They got out on land about 400 million years ago, and 80 million years ago they dominated the entire animal world. Before the dinosaurs came...

10. The reasons for the appearance of amphibians are still being explained purely hypothetically. It is believed that as a result of volcanic activity on Earth, the air temperature has risen, which has led to intensive grinding of water bodies. Reductions in the food supply for the inhabitants of the water and a drop in oxygen concentration led to the fact that part aquatic species died out, and some managed to get out on land.

11. Amphibians also include caecilians - strange creatures, which look like a cross between a worm and a snake. Worms live only in the tropics.

12. Dart frogs and leaf climbers are extremely poisonous. Rather, the mucus that they secrete to wet the skin is poisonous. One frog is enough for the South American Indians to make dozens of arrows poisonous. The lethal dose of poison for an adult is 2 milligrams.

13. Ordinary frogs that are found in ponds middle lane Russia, secrete mucus with a bactericidal effect. A frog in a glass of milk is not a grandmother's fairy tale or a way to keep milk from being stolen. This is an ancient analogue of the refrigerator - frog mucus kills lactic acid bacteria and milk does not sour longer.

14. Newts belonging to amphibians are surprisingly resilient. They regenerate all parts of their body, even their eyes. A newt can dry out to the state of a mummy, but if water gets on it, it comes to life very quickly. In winter, newts easily freeze into the ice, and then thaw.

15. Salamanders are also amphibians. They prefer warmer weather, and at the slightest cold snap they clog under branches, leaves, etc. and wait out the bad weather. Salamanders are poisonous, but their poison is not dangerous for humans - at most it can cause burning of the skin. However, it is still not worth testing your own susceptibility to salamander venom empirically.

16. Contrary to popular belief, fire salamander very much on fire. It's just that the layer of mucus on her skin is quite thick. It allows the amphibian to gain a few precious seconds to escape from the flames. The appearance of the name was facilitated not only by this fact, but also by the characteristic fiery coloring of the back of the fiery salamander.

17. Most amphibians are very good at navigating familiar terrain. And frogs are completely capable of returning to their native places even from afar.

18. Despite their low place in the hierarchy of animal classes, many amphibians see well, and some even distinguish colors. But such developed animals as dogs see the world in black and white.

19. Amphibians lay their eggs mainly in water, but there are species that bear eggs on their backs, in their mouths, and even in their stomachs.

20. Individuals of one of the salamander species grow up to 180 cm in length, which makes them the largest amphibians. And the tender meat makes giant salamanders an endangered species, salamander meat is so highly valued in China. The frogs of the Paedophryne species have the smallest size among amphibians, the average length of which is about 7.5 mm.

One of the most amazing amphibians living on earth is considered to be a frog. These representatives of the fauna do not have any features of wet, slippery and cold, they repel rather than attract our attention. However, if you take a closer look at these amphibians, you can learn a lot of interesting things about them.

So, the most interesting facts about frogs:

• In total, of the more than 5,000 species of amphibians described, almost 88% are frogs.

• Tree frogs, toads and frogs are representatives of three various kinds class of amphibians.

• The goliath frog is considered the largest frog on earth, the weight of some individuals of this species reaches more than three kilograms, and is more than 90 centimeters long. These frogs are capable of overcoming three meters in one jump.

• The smallest frog that lives on our planet lives on a cube, its “growth” is only nine millimeters.

• An equally interesting fact is that frogs have a truly unique vision, thanks to a special arrangement of their eyes, they can simultaneously look in different directions - up, sideways and forward.

• Another one of interesting moments from the life of frogs is that they do not close their eyes for a long time even during sleep.

• It is also surprising that the moist and slippery skin of amphibians has high disinfecting and antibacterial properties. Our ancestors quite often used this feature of theirs and threw them into milk so that it would not turn sour.

• Among the frogs there are really dangerous species, for example, frogs "cocos" are rightfully considered one of the most poisonous creatures on our planet.

• In nature, there is a variety of frogs whose cubs are larger than their parents. The size of an adult individual of this species does not exceed six centimeters, but their tadpoles can be safely called real giants, since their “growth” reaches as much as twenty-five centimeters, and with age they simply decrease.

• Few people know, but the number of male Amazonian necrophilic frogs is 10 times higher than the number of female representatives of this species. The males of these frogs during the mating season fertilize not only the eggs of living females, but also dead ones. Scientists have called this phenomenon "functional necrophilia."

The decisive evolutionary link between water-dwelling fish and land mammals, as well as reptiles, are some of the most amazing animals on Earth -. In this article, you will discover 10 interesting facts about amphibians.

1. Amphibians live near water

The word "amphibian" means " double life", which pretty much sums up the peculiarity of these vertebrates: they lay their eggs in the water, and also need constant access to moisture in order to survive. Only a few species of amphibians are in the middle of the evolutionary tree between fish leading a completely aquatic lifestyle, as well as terrestrial reptiles and mammals.

2. There are three main types of amphibians

Scientists divide amphibians into three main orders: tailless (frogs and toads), tailed (newts and salamanders) and legless (worms). At present, science knows about 6,000 species of frogs and toads, about 500 species of newts and salamanders, and less than 100 species of caecilians. All amphibians are technically classified as amphibians, but there are also two extinct groups of amphibians: thin vertebrae and temnospondyles, some of which have reached giant size during the Late Paleozoic.

3. Most amphibians undergo metamorphosis

True to their evolutionary position (halfway between fish and fully terrestrial vertebrates), most amphibians are born from eggs laid in the water, and short period life is spent in the aquatic environment, equipped with external gills. Then, the larvae undergo a metamorphosis in which they shed their tails, overgrow their gills, sprout strong legs, and develop primitive lungs to make their way to land at some point. The best-known larval stage is the frog tadpole, but the process of metamorphosis that occurs in them is less striking than in newts and salamanders.

4. Millions of years ago, amphibians dominated the Earth

For about 60 million years, from the beginning of the Carboniferous to the end of the Permian, amphibians were the dominant land animals on the planet, until they gave way to reptiles that developed from isolated populations of amphibians, including archosaurs (ancestors of dinosaurs) and therapsids (ancestors of mammals). The classic representative of temnospondylic amphibians was the large-headed eriops, which had a body length of up to 2 meters.

5 Amphibians Have Permeable Skin

One of the reasons amphibians should stay near bodies of water is that they have thin, water-permeable skin. If they move too far from the water, they literally dry up and die. To help keep their skin moist, amphibians constantly secrete mucus (hence the reputation of frogs as "slippery" creatures), and their dermis is littered with glands that produce toxic substances designed to protect against predators. In most species, these toxins are barely noticeable, but some frogs are so venomous that they can kill an adult human.

6. Amphibians evolved from lobe-finned fish

During the Devonian period, about 400 million years ago, lobe-finned fish ventured onto land. They have developed several key features: a musculoskeletal frame to support the weight of the body on land, as well as nostrils and leg bones, which became the impetus for subsequent evolution, during which, over several million years, the first primitive amphibians appeared, such as eucritta and crassigyrinus.

7. Like reptiles, amphibians are cold-blooded

A warm-blooded metabolism is generally reserved for more "advanced" vertebrates, so it's not surprising that amphibians are cold-blooded animals, heating up and cooling down according to ambient temperature. The advantage of cold-blooded animals is that warm-blooded animals need much more food to maintain their internal body temperature, but the main disadvantage is that they are limited in the ecosystem in which they can develop. Just a few degrees hotter or colder than their limit means imminent doom.

8 Amphibians Swallow Their Prey Whole

Unlike reptiles and mammals, amphibians do not have the ability to chew food. They have only a few teeth on the front top of their jaws, allowing them to hold writhing prey. Compensating for this shortcoming is that most amphibians have long, sticky tongues that they throw out at lightning speed to capture prey.

9 Amphibians Have Extremely Primitive Lungs

Much of the progress in vertebrate evolution goes hand in hand with the development of lung efficiency. Amphibian lungs have a relatively low internal volume, and are unable to process as much air as the lungs of reptiles and mammals. Fortunately, amphibians can absorb small amounts of oxygen through their permeable skin, which allows them to maintain their metabolic needs.

10. Amphibians are one of the most endangered animals in the world.

Their small size, permeable skin, and dependence on water make amphibians more vulnerable than most other animals and endangered. It is estimated that half of the planet's amphibian species are directly threatened due to pollution and habitat destruction, invasive species and even destruction of the ozone layer. Perhaps the biggest threat to frogs, salamanders and caecilians is chytrid fungi, which some experts attribute to global warming.