Single pass. Does the platypus lay eggs? How do platypuses reproduce? Interesting facts about platypuses What brings the platypus closer to cats

The platypus is an amazing animal that lives only in Australia, on the island of Tasmania. The outlandish miracle belongs to mammals, but, unlike other animals, it lays eggs like an ordinary bird. Platypuses are egg-laying mammals - a rare species of animals that have survived only on the Australian continent.

Discovery history

Strange creatures can boast of an unusual story of their discovery. The first description of the platypus was given by Australian pioneers in the early 18th century. For a long time, science did not recognize the existence of platypuses and considered the mention of them to be an inept joke of Australian residents. Finally, at the end of the 18th century, scientists at a British university received a parcel from Australia containing the fur of an unknown animal, similar to a beaver, with paws like those of otters and a nose like that of an ordinary domestic duck. Such a beak looked so ridiculous that scientists even shaved off the hair on the muzzle, believing that Australian pranksters sewed a duck nose to the skin of a beaver. Finding no seams, no traces of glue, pundits just shrugged. No one could understand where he lives or how the platypus breeds. Only a few years later, in 1799, the British naturalist J. Shaw proved the existence of this miracle and gave the first detailed description of the creature, which was later given the name "platypus". A photo of a bird animal can only be taken in Australia, because this is the only continent on which these exotic animals currently live.

Origin

The appearance of platypuses refers to those distant times when there were no modern continents. All land was united into one huge continent - Gondwana. It was then, 110 million years ago, that platypuses appeared in terrestrial ecosystems, taking the place of the recently extinct dinosaurs. Migrating, platypuses settled throughout the mainland, and after the collapse of Gondwana, they remained to live on a large stretch of the ex-continent, which was later called Australia. Due to the isolated location of their homeland, the animals have retained their original appearance even after millions of years. Various species of platypus once inhabited the vastness of the entire land, but only one species of these animals has survived to this day.

Classification

For a quarter of a century, the leading minds of Europe puzzled over how to classify the overseas beast. Of particular difficulty was the fact that the creature turned out to have a lot of signs that are found in birds, animals, and amphibians.

The platypus saves all fat reserves in the tail, and not under the hair on the body. Therefore, the tail of the beast is solid, heavy, able not only to stabilize the movement of the platypus in the water, but also serves as an excellent means of defense. The weight of the animal fluctuates around one and a half to two kilograms with a length of half a meter. Compare with a domestic cat, which, with the same dimensions, weighs much more. Animals do not have nipples, although they produce milk. The temperature of the bird animal is low, barely reaching 32 degrees Celsius. This is much lower than that of mammals. Among other things, platypuses have another striking feature in the literal sense. These animals can hit with poison, which makes them quite dangerous opponents. Like almost all reptiles, the platypus lays eggs. Platypuses have in common with snakes and lizards both the ability to produce poison and the arrangement of the limbs, like those of amphibians. Amazing walk of the platypus. He moves by bending his body like a reptile. After all, his paws do not grow from the bottom of the body, like birds or animals. The limbs of this either a bird or an animal are located on the sides of the body, like those of lizards, crocodiles or monitor lizards. High on the head of the animal are the eyes and ear holes. They can be found in depressions located on each side of the head. The auricles are absent, while diving, he closes his eyes and ears with a special skin fold.

mating games

Every year, platypuses go into hibernation, which lasts 5-10 short winter days. This is followed by a mating period. How the platypus breeds, scientists have found out relatively recently. It turns out that, like all major events in the life of these animals, the courtship process takes place in the water. The male bites the tail of the female he likes, after which the animals circle each other in the water for some time. They do not have permanent pairs, the children of the platypus remain only with the female, who herself is engaged in their cultivation and education.

Waiting for the cubs

A month after mating, the platypus digs a long deep hole, filling it with armfuls of wet leaves and brushwood. The female wears everything necessary, covering her paws and tucking her flat tail from below. When the shelter is ready, the expectant mother is placed in the nest, and the entrance to the hole is covered with earth. In this nesting chamber, the platypus lays its eggs. The clutch usually contains two, rarely three small whitish eggs, which are glued together with a sticky substance. The female incubates the eggs for 10-14 days. The animal spends this time curled up in a ball on the masonry, hidden by wet leaves. At the same time, the female platypus can occasionally leave the hole in order to have a snack, clean itself and moisten the fur.

Birth of platypuses

After two weeks of residence, a small platypus appears in the clutch. The baby breaks eggs with an egg tooth. After the baby comes out of the shell, this tooth falls off. After birth, the female platypus moves the cubs onto her abdomen. The platypus is a mammal, so the female feeds her cubs with milk. Platypuses do not have nipples, milk from the enlarged pores on the parent's stomach flows down the wool into special grooves, from where the cubs lick it. The mother occasionally goes outside to hunt and clean herself, while the entrance to the hole is clogged with earth.
For up to eight weeks, cubs need their mother's warmth and can freeze if left unattended for a long time.

At the eleventh week, the eyes of small platypuses open, after four months the babies grow up to 33 cm in length, grow hair and completely switch to adult food. A little later, they leave the hole and begin to lead an adult lifestyle. At the age of one year, the platypus becomes an adult sexually mature individual.

Platypuses in history

Before the appearance of the first European settlers on the shores of Australia, platypuses had practically no external enemies. But the amazing and valuable fur made them an object of trade for white people. Skins of platypuses, black-brown on the outside and gray on the inside, at one time were used to make fur coats and hats for European fashionistas. Yes, and the locals did not hesitate to shoot the platypus for their needs. At the beginning of the twentieth century, the decline in the number of these animals became rampant. The naturalists sounded the alarm, and the platypus joined the ranks. Australia began to create special reserves for amazing animals. Animals were taken under state protection. The problem was complicated by the fact that the places where the platypus lives must be protected from the presence of a person, since this animal is shy and sensitive. In addition, the mass distribution of rabbits on this continent deprived platypuses of their usual nesting places - eared aliens occupied their holes. Therefore, the government had to allocate huge areas, protected from third-party interference, in order to preserve and increase the population of platypuses. Such reserves have played a decisive role in preserving the population of these animals.

Platypuses in captivity

Attempts have been made to resettle this animal in zoos. In 1922, the first platypus arrived at the New York Zoo and lived in captivity for only 49 days. Because of their desire for silence and increased shyness, animals have not mastered zoos; in captivity, the platypus reluctantly lays eggs, offspring were only obtained a few times. No cases of domestication of these exotic animals by humans have been recorded. Platypuses were and remain wild and distinctive Australian Aborigines.

Platypus today

Now platypuses are not considered Tourists are happy to visit the places where the platypus lives. Travelers willingly publish photos of this animal in their stories about Australian tours. Images of a bird animal serve as a hallmark of many Australian goods and manufacturing companies. Along with the kangaroo, the platypus has become a symbol of the Australian continent.

Monotremes (or oviparous) - the most primitive among modern mammals, retaining a number of archaic structural features inherited from reptiles (oviposition, the presence of a well-developed coracoid bone not connected to the scapula, some details of the articulation of the bones of the skull, etc.) - Their development is so called marsupials (small bones of the pelvis) are also regarded as a heritage of reptiles.

In the presence of distinct coracoid bones, monotremes differ from marsupials and other mammals, in which this bone has become a simple outgrowth of the scapula. At the same time, hairline and mammary glands are two interrelated features that are characteristic of mammals. However, the mammary glands of ovipositors are primitive and similar in structure to the sweat glands, while the mammary glands of marsupials and higher mammals are grape-shaped and similar to the sebaceous glands.

Quite numerous similarities of monotremes with birds are adaptive rather than genetic traits. The laying of eggs by these animals brings monotremes closer to reptiles than to birds. However, in the egg, the yolk in monotremes is much less developed than in birds. The keratinized egg shell is composed of keratin and also resembles the shell of reptile eggs. Birds are also reminiscent of such structural features as some reduction of the right ovary, the presence of pockets in the digestive tract resembling the goiter of birds, and the absence of an external ear. However, these similarities are more of an adaptive nature and do not give the right to speak of any direct relationship between monotremes and birds.

In terms of body temperature, monotremes occupy an intermediate position between poikilothermic (reptiles) and true warm-blooded (mammals and birds). The body temperature of the echidna fluctuates around 30°C, and that of the platypus around 25°C. But these are only average figures: they change depending on the ambient temperature. So, the body temperature of the echidna when the temperature of the environment changes from + 5 ° to + 30 ° C increases by 4-6 °.

Curiously, the appearance of the first dinosaurs and other archosaurs, at one time, was marked by a massive (but not complete) extinction of therapsids, the highest forms of which were very close to monotremes in their organization, and, according to some assumptions, may have had mammary glands and hair. At present, the detachment of monotremes has 2 families: echidnas and platypuses; 3 types.

2 families: platypuses and echidnas
Range: Australia, Tasmania, New Guinea
Food: insects, small aquatic animals
Body length: 30 to 80 cm

Subclass oviparous mammals represented by only one detachment - single-pass. This detachment unites only two families: platypus and echidna. single pass are the most primitive living mammals. They are the only mammals that, like birds or reptiles, reproduce by laying eggs. Oviparous feed their young with milk and therefore are classified as mammals. Female echidnas and platypuses do not have nipples, and the young lick the milk secreted by the tubular mammary glands directly from the fur on the mother's belly.

amazing animals

Echidnas and platypuses- the most unusual representatives of the class of mammals. They are called single-pass because both the intestines and the bladder of these animals open into one special cavity - the cloaca. Two oviducts in monotreme females also go there. Most mammals do not have a cloaca; this cavity is characteristic of reptiles. The stomach of oviparous is also amazing - like a bird's goiter, it does not digest food, but only stores it. Digestion takes place in the intestines. These strange mammals even have a lower body temperature than others: without rising above 36°C, it can drop to 25°C depending on the environment, like in reptiles. Echidnas and platypuses are voiceless - they do not have vocal cords, and only young platypuses have toothless - rapidly decaying teeth.

Echidnas live up to 30 years, platypuses - up to 10. They live in forests, steppes overgrown with shrubs, and even in mountains at an altitude of up to 2500 m.

Origin and discovery of oviparous

Short Fact
Platypuses and echidnas are venomous mammals. On their hind legs they have a bone spur, through which a poisonous liquid flows. This poison causes an early death in most animals, and severe pain and swelling in humans. Among mammals, in addition to the platypus and echidna, only a representative of the order of insectivores is venomous - an open tooth and two species of shrews.

Like all mammals, oviparous descend from reptilian ancestors. However, they separated from other mammals quite early, choosing their own path of development and forming a separate branch in the evolution of animals. Thus, the oviparous were not the ancestors of other mammals - they developed in parallel with them and independently of them. Platypuses are more ancient animals than echidnas, which evolved from them, changed and adapted to the terrestrial way of life.

Europeans learned about the existence of egg-laying almost 100 years after the discovery of Australia, at the end of the 17th century. When the skin of a platypus was brought to the English zoologist George Shaw, he decided that he was simply played, the appearance of this bizarre creation of nature was so unusual for Europeans. And the fact that echidnas and platypuses reproduce by laying eggs has become one of the greatest zoological sensations.

Despite the fact that the echidna and the platypus have been known to science for quite a long time, these amazing animals are still presenting new discoveries to zoologists.

wonder beast, platypus as if assembled from parts of different animals: his nose is like a duck's beak, a flat tail with a shovel seems to be taken from a beaver, webbed paws look like flippers, but are equipped with powerful claws for digging (when digging, the membrane bends, and when walking it gathers into folds, without interfering with free movement). But for all the seeming absurdity, this beast is perfectly adapted to the way of life that it leads, and has hardly changed over millions of years.

At night, the platypus hunts for small crustaceans, mollusks and other small aquatic animals. The tail-fin and webbed paws help him to dive and swim well. The eyes, ears and nostrils of the platypus close tightly in the water, and it finds its prey in the dark under water with the help of a sensitive "beak". On this leathery "beak" are electroreceptors that can pick up weak electrical impulses emitted by movement of aquatic invertebrates. Reacting to these signals, the platypus instantly searches for prey, fills the cheek pouches, and then slowly eats the caught on the shore.

All day the platypus sleeps near the pond in a hole dug by powerful claws. The platypus has a dozen such holes, and each has several exits and entrances - not an extra precaution. To breed offspring, the female platypus prepares a special hole lined with soft leaves and grass - it is warm and humid there.

Pregnancy lasts a month, and the female lays one to three leathery eggs. Mother platypus incubates eggs for 10 days, warming them with her body. Newborn tiny platypuses, 2.5 cm long, live on their mother's belly for another 4 months, feeding on milk. The female spends most of her time lying on her back and only occasionally leaves the burrow to feed. Leaving, the platypus wall up the cubs in the nest so that no one will disturb them until she returns. At the age of 5 months, matured platypuses become independent and leave their mother's hole.

Platypuses were mercilessly exterminated because of their valuable fur, but now, fortunately, they are taken under the strictest protection, and their numbers have increased again.

A relative of the platypus, it does not look like him at all. She, like the platypus, is an excellent swimmer, but she does it only for pleasure: she does not know how to dive and get food under water.

Another important difference: the echidna has brood bag- pocket on the belly, where she puts the egg. The female, although she raises her cubs in a comfortable hole, can safely leave her - an egg or a newborn cub in her pocket is reliably protected from the vicissitudes of fate. At the age of 50 days, the little echidna already leaves the bag, but for about 5 months it lives in a hole under the auspices of a caring mother.

Echidna lives on the ground and feeds on insects, mainly ants and termites. Raking termite mounds with strong paws with hard claws, it extracts insects with a long and sticky tongue. The body of the echidna is protected by needles, and in case of danger it curls up into a ball, like an ordinary hedgehog, exposing the enemy with a prickly back.

wedding ceremony

From May to September, the mating season begins for the echidna. At this time, the female echidna enjoys special attention from males. They line up and follow her in single file. The procession is led by the female, and the grooms follow her in order of seniority - the youngest and most inexperienced close the chain. So, in a company, echidnas spend a whole month, looking for food together, traveling and relaxing.

But the rivals cannot coexist peacefully for long. Demonstrating their strength and passion, they begin to dance around the chosen one, raking the ground with their claws. The female finds herself in the center of a circle formed by a deep furrow, and the males begin to fight, pushing each other out of the ring-shaped pit. The winner of the tournament gets the favor of the female.

Subclass Primal Beasts (Prototheria)

Order Monotremes, or Oviparous (Monotremata) (E. V. Rogachev)

Monotremes (or oviparous) are the most primitive among modern mammals, retaining a number of archaic structural features inherited from reptiles (oviposition, the presence of a well-developed coracoid bone not connected to the scapula, some details of the articulation of the bones of the skull, etc.). Their development of the so-called marsupial bones (small bones of the pelvis) is also considered as a legacy of reptiles.

Adult oviparous teeth are absent. In 1888, milk teeth were found in a platypus cub, which disappear in an adult animal; these teeth are varied in structure, as in higher mammals, and the two largest teeth on each jaw have the location and appearance of molars. In terms of body temperature, monotremes occupy an intermediate position between poikilothermic (reptiles) and true warm-blooded (mammals and birds). The body temperature of the echidna fluctuates around 30°C, and that of the platypus around 25°C. But these are only average figures: they change depending on the ambient temperature. So, the body temperature of the echidna when the temperature of the environment changes from + 5 ° to + 30 ° C increases by 4-6 °.

At present, the order of monotremes has 5 living representatives belonging to two families: the platypus and 4 species of echidnas. All of them are distributed only in Australia, New Guinea and Tasmania (Map 1).

Family Platypuses (Ornithorhynchidae)

The only member of the family platypus(Ornithorhynchus anatinus) - was discovered at the very end of the 18th century. during the colonization of New South Wales. In the list of animals of this colony published in 1802, the platypus was first mentioned as "an amphibious animal from the genus of moles ... Its most curious quality is that it has a duck's beak instead of the usual mouth, allowing it to eat in the mud, like birds. ..". It was also noted that this animal digs a hole for itself with its claws. In 1799 Shaw and Nodder gave it a zoological name. European colonists called him "platypus", "duck mole", "water mole". At present, the Australians call it "platypus" (Fig. 14).

The very first scientific description of the platypus marked the beginning of fierce disputes. It seemed paradoxical that a furry mammal could have a duck's beak and webbed feet. The first platypus skins brought to Europe were considered fake, the product of skilled oriental taxidermists who deceived gullible European sailors. When this suspicion dissipated, the question arose as to which group of animals he should be assigned. The "secrets" of the platypus continued to be revealed: in 1824, Meckel discovered that the platypus has glands that secrete milk. It was suspected that this animal lays eggs, but this was proved only in 1884.

The platypus is a brown-furred animal, about 65 cm long, including the length of a flattened tail similar to that of a beaver. The head ends in the famous "duck's beak", which is really just a snout in the form of an extended beak, covered with a special kind of skin rich in nerves. This "beak" of the platypus is a tactile organ that also serves to obtain food.

The head of the platypus is round and smooth; there is no external ear. The front paws are strongly webbed, but the web that serves as an animal when swimming is folded when the platypus walks on land or if it needs claws to dig a hole. The webs on the hind legs are much less developed. The main role in digging and swimming is played by the front paws, the hind limbs are of great importance when moving on land.

The platypus usually spends about two hours a day in the water. It feeds twice: early in the morning and in the evening twilight. He spends most of his time in his hole, on land.

The platypus feeds on small aquatic animals. He stirs up the silt at the bottom of the reservoir with his beak and catches insects, crustaceans, worms and molluscs. Under water, he feels free, unless, of course, it is possible to catch his breath on the surface from time to time. Diving and rummaging in the silt, he is guided mainly by touch; his ears and eyes are protected by fur. On land, the platypus, in addition to touch, is guided by sight and hearing (Fig. 15).

Platypus burrows are located outside the water, including the entrance, located somewhere under the overhanging shore at a height of 1.2-3.6 m above the water level. Only an exceptionally high flood can flood the entrance to such a hole. An ordinary hole is a semicircular cave dug under the roots of trees, with two or more entrances.

Every year, the platypus goes into a short winter hibernation, after which it has a breeding season. Males and females meet in the water. The male grabs the tail of the female with his beak, and for some time both animals swim in a circle, after which mating takes place.

When the time comes for the female to lay eggs, she digs a special hole. First, it digs a gallery in the slope of the coast from 4.5 to 6 m, at a depth of about 40 cm below the soil surface. At the end of this gallery, the female rips out the nesting chamber. In the water, the female searches for nest material, which she then brings to the hole with the help of her tenacious tail. She builds a nest from water plants, willow twigs or eucalyptus leaves. Too hard material, the expectant mother carefully crushes. Then she clogs the entrance to the corridor with one or more earthen plugs, each 15-20 mm thick. cm; plugs are made with the help of a tail, which uses a spatula like a mason. Traces of this work can be constantly seen on the tail of the female platypus, which in its upper part is shabby, devoid of hair. Thus, the female clogs herself in a dark shelter inaccessible to predators. Even a man could not reveal the secret of her nesting shelter for a long time. Having finished this painstaking and complex work, the female lays eggs.

The first time a platypus laid eggs was observed in 1884 by Caldwell in Queensland. After that, she was traced to the Hillsville Nature Reserve in Victoria. These eggs are small (less than 2 cm in diameter), rounded, surrounded by a dirty white shell, consisting not of lime, as in birds, but of a soft, elastic horn-like substance, so that they can easily be deformed. Usually there are two eggs in the nest, sometimes one, three or even four.

The duration of incubation may vary. A well-known expert on Australian animals, David Flay, found out that incubation in a platypus does not exceed 10 days, and can last as long as a week, provided that the mother is in the nest. During incubation, the female lies, curved in a special way, and holds the eggs on her body.

The mammary glands of the platypus, discovered by Meckel in 1824, lack a nipple and open outwards with simple dilated pores. From them, milk flows down the mother's coat, and the cubs lick it off. They are growing fast. During their feeding, the mother also feeds heavily; a case is known when a nursing female ate earthworms and crustaceans overnight in an amount almost equal to her own weight.

The cubs are blind for 11 weeks, then their eyes open, but they remain in the hole for another 6 weeks. These babies, which feed only on milk, have teeth; as the animal grows, the milk teeth disappear and are replaced by simple horny plates. Only after 4 months, young platypuses go on their first brief excursion into the water, where they begin to clumsily search for food. The transition from dairy to adult nutrition is gradual. Platypuses are well tamed and live up to 10 years of age in captivity.

Platypuses are found in Queensland, New South Wales, Victoria, parts of South Australia and Tasmania. They are currently most numerous in Tasmania (Map 1).

The platypus is not picky about the composition of the water in which it seeks food. It carries both the cold and clear waters of the mountain streams of the Australian Blue Mountains, and the warm and muddy waters of the rivers and lakes of Queensland.

Quaternary remains of the platypus have been found in southern Queensland. Fossil platypuses resembled modern ones, but were smaller in size.

Before the migration of man to Australia, the enemies of the platypus were few. Rarely attacked him monitor lizard(Varanus varius) python(Pithon variegatus) and a seal swimming in rivers sea leopard. The rabbits brought by the colonists created a dangerous situation for him. By burrowing, rabbits disturbed the platypus everywhere, and in many areas it disappeared, giving way to their territory. European settlers also pursued the platypus for its pelt. Many animals fell into traps set along the banks of the rivers for rabbits, and into the tops of fishermen.

Wherever people destroyed or disturbed the platypus, the surviving animals left these places. Where the man did not bother him, the platypus perfectly endured the neighborhood with him. To ensure the existence of the platypus, the Australians created a system of reserves and "refuges", among which the most famous are the Hillsville Reserve in Victoria and the West Burley Reserve in Queensland.

The platypus is an easily excitable, nervous animal. According to D. Flay, the sound of a voice or steps, some unusual noise or vibration is enough for the platypus to be out of balance for many days, or even weeks. Therefore, for a long time it was not possible to transport platypuses to zoos in other countries. In 1922, the first platypus ever seen in other countries arrived at the New York Zoo; here he lived only 49 days; every day for an hour it was shown to the public. Transportation became possible thanks to G. Burrell, who invented an artificial dwelling for the platypus, consisting of a water tank (reservoir), a sloping labyrinth imitating a hole with rubber "soil", and a stock of worms to feed the animal. To show the animal to the public, the wire cover of the living chamber of the platypus burrow was displaced.

In the same zoo in New York, platypuses were imported twice: in 1947 and 1958. These transportations were organized by D. Flay. In 1947, three platypuses were transported to New York by sea; one of them died after 6 months, and the other two lived in the zoo for 10 years. In 1958, three more platypuses were airlifted to New York.

Echidna family (Tachyglossidae)

The second family of the monotreme order includes echidnas, covered with needles, like porcupines, but reminiscent of anteaters in type of nutrition. The sizes of these animals usually do not exceed 40 cm. The body is covered with needles, the length of which can reach 6 cm. The color of the needles varies from white to black. Under the needles, the body is covered with short brown hair. The echidna has a thin, pointed muzzle 5 cm ending in a narrow mouth. Longer tufts of hair are usually developed around the ears. The tail is almost not expressed, there is only something like a projection from behind, covered with needles (Table 2).

There are currently 2 genera of echidnas: echidna proper(genus Tachyglossus) living in Australia, and new guinea prochidna(genus Proechidna). In the genus Tachyglossus, 2 species are distinguished: Australian echidna(T. aculeatus), one of the subspecies of which is endemic to New Guinea, and Tasmanian echidna(T. se ~ tosus), characterized by larger sizes and thick hair, from which sparse and short needles stick out. The difference in the fur of these animals is probably due to the colder and wetter climate of Tasmania.

Echidna is found in Australia, in the eastern half of the mainland and at its western tip, in Tasmania and New Guinea. The Tasmanian echidna is found in Tasmania and on several Bass Strait islands.

The discovery of echidna early in the colonization of New South Wales did not immediately receive the attention it deserved. In 1792, Shaw and Nodder described the Australian echidna and named it Echidna aculeata. In the same year, a Tasmanian species was discovered, described by Geoffroy as Echidna setosa. Echidna is a purely terrestrial animal. It lives in dry bush (thickets of bushes), preferring rocky areas. She does not burrow. Her main defense is needles. When disturbed, the echidna curls up into a ball like a hedgehog. With the help of claws, it can partially burrow into loose earth; burying the front of the body, it exposes the enemy only to the needles pointing backwards. During the day, hiding in the voids under the roots, stones or in hollows, the echidna rests. At night, she goes in search of insects. In cold weather, she stays in her lair, falling into a short hibernation, like our hedgehogs. Stocks of subcutaneous fat allow her, if necessary, to starve for a month or more.

The brain of the echidna is more developed than that of the platypus. She has very fine hearing, but poor eyesight: she sees only the closest objects. During his excursions, mostly nocturnal, this animal is guided mainly by the sense of smell.

Echidna feeds on ants, termites and other insects, and sometimes other small animals (earthworms, etc.). She destroys anthills, moves stones, pushing them with her paws, even rather heavy ones, under which worms and insects hide.

The strength of the echidna's muscles is amazing for an animal of such a small size. There is a story about a zoologist who locked an echidna in his kitchen for the night. The next morning he was very surprised to see that the echidna had moved all the furniture in the kitchen.

Having found an insect, the echidna throws out its thin, long and sticky tongue, to which the prey sticks.

The echidna has no teeth at all stages of its development, but on the back of its tongue there are horny teeth that rub against the pectinate palate and grind the caught insects. With the help of the tongue, the echidna swallows not only insects, but also earth and detritus, which, getting into the stomach, complete the grinding of food, similar to how it happens in the stomach of birds.

Like the platypus, the echidna incubates the eggs and feeds the young with milk. A single egg is placed in a primitive bag, which is formed by the breeding season (Fig. 16). How the egg gets into the bag is still unknown. G. Burrell proved that the echidna cannot do this with the help of its paws, and put forward another hypothesis: it has a sufficiently flexible body so that, by bending, the female could lay the egg directly into the abdominal bag. One way or another, the egg "hatches" in this bag, where the baby hatches from it. To get out of the egg, the cub breaks the shell with the help of a horny bump on the nose.

Then he sticks his head into a hairy pouch where the mammary glands open, and licks the milk secretions from the hairs of this pouch. The calf stays in the pouch for quite some time until its quills begin to develop. Then the mother leaves him in some shelter, but for some time she visits him and feeds him with milk.

Echidna tolerates captivity well if she has protection from an excess of the sun, from which she suffers greatly. She enjoys drinking milk, eating eggs and other food that can fit in her narrow, tube-like mouth. Her favorite delicacy is raw eggs, in the shell of which a hole is punched, where the echidna can stick her tongue. Some echidnas have lived in captivity for up to 27 years.

Aborigines who love to eat echidna fat often hunted it, and in Queensland they even specially trained dingoes to hunt echidnas.

prochidni(genus Proechidna) are found in New Guinea. They differ from Australian echidnas in having a longer and more curved muzzle ("beak") and high three-toed limbs, as well as small external ears (Fig. 17). In the Quaternary period, two now extinct species of echidnas are known, but this group is unknown in older deposits. The origin of echidnas is as mysterious as that of the platypus.

1. Is the statement true: “Care for offspring leads to a reduction in the birth rate in animals”? Prove your point

Yes, that's right. Bearing cubs, live birth, feeding with milk, caring for offspring ensure the best safety of young animals in a diverse environment.

2. Name the smallest and largest representative of the class Mammals

Pygmy shrew - 4 cm

Blue whale - up to 33 cm

3. List the specific features of mammals

Two pairs of five-fingered limbs; cervical spine - from 7 vertebrae; teeth differ in structure and function; there are milk, sweat, glands; the body is covered with wool; four-chambered heart; the cerebral cortex and sensory organs are developed; four-chambered heart

4. It is known that crocodiles have teeth of different sizes. But it is the teeth of mammals that are called specialized. Explain why

In crocodiles, the teeth are different only in size, while in mammals they are different not only in size, but also in their functions: there are incisors, fangs, molars

Detachment Single pass

1. What signs bring ovipositors closer to reptiles?

Body temperature is not constant. They reproduce by laying eggs. The eggs are covered with a keratinized shell resembling that of a reptile.

2. Read the text. What animal is described here?

Lives in Australia. Its body is covered with needles, its beak is tubular. Body temperature is unstable - up to 30 ° C. It reproduces by eggs, which it bears in a leathery bag on its belly. Uses sharp claws for burrowing

Answer: echidna

3. Why are primitive animals subject to protection?

First animals - very rare animals

Order Marsupials

1. What feature of the life cycle of this group of mammals is reflected in the name of this order?

Marsupials have a special fold of skin on their belly in the form of a pocket where newborns are placed.

2. Fill in the table by choosing from the proposed habitat options and food diet for marsupial mammals indicated in the table

Habitat:

1. lives in trees

2. lives on eucalyptus trees

3. lives in the soil, digs holes

4. lives near streams and rivers

A. feeds on small fish and aquatic invertebrates

B. feeds on insects, larvae, worms

V. feeds on eucalyptus leaves

G. feeds on birds and rodents

D. eats plant and animal food

Order Insectivores

1. Name the representatives of the order Insectivores, for which the name of the order only partially reflects their nutritional diet

Shrew, mole, desman

2. Name the smallest and largest representative of the detachment

Shrew baby - up to 4 cm

Desman ordinary - up to 22 cm

3. Suggest the meaning for this group of animals of an elongated muzzle and proboscis

With their help, insectivores catch insects from their minks and passages.

4. Consider fig. 129 of the textbook (p. 161). Name which of the insectivores shown in the figure lives in the soil

Order Chiroptera

1. What is common in the way birds and bats move?

Birds and bats are capable of long flapping flight

2. Name two suborders of bats

1. Fruit bats

2. Bats

3. What method of orientation allows bats to actively lead a nocturnal lifestyle?

Bats are capable of echolocation. In flight, they emit high-frequency sounds (ultrasounds). Sound waves reflected from obstacles are picked up by the large auricles of bats. The distance to the object is determined by the nature of the reflected sound of the mouse.

4. Why do we rarely meet bats in nature, although they are quite widespread?

Bats are active at night

5. What is the significance of the decrease in body temperature in bats during sleep?

Their metabolism slows down and energy consumption slows down.

6. Look at the pictures. Label under each picture the name of the order and species to which the animal belongs.

Detachment Chiroptera. View Red Vespers

Order Insectivora. View Desman

Detachment Single pass. Species Platypus

Order Marsupials. Species Tasmanian wolf

Order Insectivora. View Mole

Categories
- Dogs
- cats
- Cat care
- Pets
- free birds
- Birds
- bird breeding
- poultry
- Diseases of cats
- Dog diseases

Popular