Mammals that lay eggs belong to. Oviparous mammal: description, features, reproduction and species. Electroreceptors of oviparous mammals

Long before white-skinned aliens arrived on the Australian continent, extraordinary creatures lived there - half people, half monkeys, and next to them their relatives - a whole family of totemic animals.

This is approximately how the aborigines imagine times gone by. From then to the present day, animals have been preserved in Australia that, it would seem, should have long ago turned into fossils.

Giant snake and ostrich dinosaur

First of all, these are the colossal-sized snakes of Central Australia: the volunqua and their relatives, the mindi, or rainbow snakes. But the spellbound contemplation of this “rainbow” may be the last thing you see in your life. Fortunately, the reptile emits a sickening odor that warns of its presence. Other misfortunes are also attributed to Mindy: the snake is believed to bring with it an epidemic of syphilis.

These snakes live in coastal areas and are almost unknown in inland areas, where barely 500 millimeters of rainfall a year. For local tribes giant snakes served as prototypes of fantastic creatures from numerous traditions and legends.

One of them is the legend about the evil yero, either a snake or an eel, who lives in some northwestern lakes. The throat of this creature is incredibly wide. According to the beliefs of the Australian aborigines, whirlpools can be born in it.

“On the Atherton Plateau in Queensland,” says G. Whitley, an ichthyologist from the Australian Museum, “there is a lake that I could not get the rowers of my boat to cross. They believed that some mythical animal lived in the depths of the lake.”

What kind of animal is this? Probably, the image of a fairy-tale snake embodied ideas about all the dangers that await a person sailing over great depths on a light boat. This is a unique form of recording the experience of generations among the aborigines.

No less impressive are the legends about the animal called Gauarge unusual beast, leading a semi-aquatic lifestyle. He drags down to the bottom everyone who dares to swim through his domain. Remarkably, the gauarge is described as an emu, but an emu without feathers!

If you ever get a chance to look at a plucked Australian ostrich, its carcass will look like Struthiomimus, one of the dinosaurs whose name means “which resembles an ostrich.”

Many people believe that dinosaurs are definitely monsters huge size. However, among them there were specimens no larger than a chicken. Between these dwarfs and the giant iguanodonts lies Struthiomimus, an ostrich dinosaur that lived in swampy coastal lowlands, but also found refuge in the water.

It can be assumed that the aborigines met or retained in their legends the memory of encounters with a living dinosaur. In any case, it is more useful to treat the legend of the Gauarg with attention rather than with contempt.

Dwarf eating children

It is quite easy to find an explanation for the old Australian legend about the mockingbird who is not taken by death. Now zoologists are well aware that this is none other than the bird Dacelo gigas, nicknamed Martin the Hunter. The night cries of this bird still instill fear in local residents.

One of these “nightmarish” creatures has long been considered yara maya-vho. The Aborigines claim that this is a small, toothless man, similar to a frog. It lives on palm trees and has suckers on its fingers. They say that with these suckers he clings to the body of a child who finds himself under a tree and does not let go until he has sucked all the blood out of him.

It is surprising that zoologists could not identify this creature for so long. After all, apart from its bloodthirsty disposition, there is so much information about the animal that it is as easy for a zoologist to recognize it as for a peasant to guess a riddle: who runs on two legs, is covered with feathers and cries to the crow?

There is no doubt that the mysterious yara is none other than the ghost tarsier (Tarsius spectrum). This is a small furry animal with a flat face and huge eyes. It can be considered the most mysterious of all primates.

Being among the branches, it can take a stand on its hind legs. Its appearance is so reminiscent of a human that the English anatomist Wood-Jones and his Dutch colleague A. Hubrecht considered it the creature closest to man! Of course, this is an exaggeration, but the animal has outstanding qualities that are unique to it.

He is only twelve to twenty centimeters tall. The huge eyes are dilated to enhance night vision, and there are thickenings with suction cups at the tips of the long fingers. The tarsier's foot is so long (hence the animal's name) that, unlike other primates, it is forced to rely only on its toes when walking. But the tarsier jumps beautifully, resembling a furry frog, but its jumps are much easier. Weighing only about 140 grams, it allows him to make two-meter jumps, while rising up to sixty centimeters! Of course, the tarsier is far from toothless, but when it opens its V-shaped mouth, which is quite ominous, it seems that it has no teeth.

The tarsier is the only primate that can be considered completely carnivorous. He sometimes gets to try fruits, but the main food consists of insects, lizards, birds and even small mammals. For them, a tarsier is a bloodthirsty robber.

If we add to the described properties of the tarsier its night look life, then one can understand why this rare animal has become the subject of all kinds of superstitions.

There is only one reason that prevented zoologists from seeing a ghost tarsier in the Yara. This is that the latter is not found in Australia. It is found only in the Malay Archipelago: Sumatra, Borneo, Sulawesi and several Philippine islands.

Previously, tarsiers were much more widespread than they are now. In the sediments of the early Tertiary period, these strange “little men” are found throughout Europe and North America. But today in Australia there are no placental mammals in the wild - except for those, of course, that were brought by humans, that is, rats, dingoes and others.

Once upon a time, mammals with a placenta replaced marsupials throughout the planet, but were unable to penetrate the “watershed”, that is, the invisible line that zoologists drew between Bali and Lombok, and further north, between Borneo and Sulawesi. In short, they failed to get to either New Guinea or Australia, where marsupials flourished in complete safety before the human invasion.

This is why it is almost incredible that the tarsier could live in Australia. Perhaps solving the mystery of this animal will help shed light on the problem of the origin of Australian tribes, which has been worrying anthropologists for so long. It can be assumed that the legends about the Yara came to the mainland from the islands of Borneo, Sumatra and Sulawesi, were passed down from generation to generation and have survived to this day.

It is undeniable that the tiny tarsier, completely harmless to humans, keeps not only Australia, but the entire Malay region at bay. In addition, it seems likely to me that this same animal gave rise to the legend of the “forest demon”, widespread in the Philippines.

"Animals on Bird Legs"

No matter how amazing the animals from the folklore of Oceania are, a real boom in fantastic tales came after their arrival on the Australian continent white man, so disposed to all kinds of fables. We hasten to add that most of the rumors had a basis in reality.

When, at the beginning of the 17th century, brave Dutch sailors began to explore the Australian seas in search of rich and fertile islands, they had to land on the shores, it seemed endless land, which they called New Holland out of nostalgic feelings.

In this country, they said, there lives a large animal, like a man, who has a long tail and a small head, like a goat. His hind legs are like those of a bird, and he can hop on them like a frog. In 1640, the first scientific description of the animal was given, accompanied by a fantastic drawing.

A century later, Captain James Cook, stopping near the mainland to repair a ship that had hit a reef, took the opportunity to visit mysterious land. It penetrated deep into the territory in the Trinity Bay area. On July 9, 1770, two men from his crew, one of them the famous naturalist Joseph Banks, went hunting to replenish their meat supplies. As Cook later said, they walked several miles and met four “those very animals on bird legs.” Banks sent his greyhound after them, but she quickly fell behind; thick grass, over which the animals easily jumped, prevented her from running.

Cook soon learned that the natives called the jumper a kangaroo. However, this name was never found in any of the Australian dialects...

The information received from such an educated and meticulous person in his reports as James Cook did not raise doubts, so twenty years later the word “kangaroo” was already used as scientific name in books on zoology.

But what surprised Cook most of all was that the jumpers carry babies with them in a pocket on their stomachs.

A striking feature of the animal world of Australia soon became clear: all mammals living on the mainland had the same pockets for their young.

Mammals that lay eggs

But even more unexpected surprises awaited the scientific world. In 1797, an animal called the “water mole” was discovered in the southern part of New Gaul. In fact, this strange animal looked more like an otter. He had flippers on his legs. But if membranes between the fingers can be assumed in a mammal, then what could European zoologists say about the presence of a duck beak!

The first stuffed platypus examined by members of the Royal Zoological Society was found to be a fake.

The fact is that animal samples coming from the East were sometimes so skillfully forged by the Chinese that scientists had long been accustomed to “sensational” fakes and looked skeptically at any surprise. How many times have travelers brought mummies of sirens to Europe, who, according to legend, live somewhere in Indian Ocean! In fact, they were made from the body and head of a monkey, the legs of a bird and the tail of a fish. “Water mole”, consisting simultaneously of parts of the body of a bird and a mammal, and this seemed undeniable, belonged to skillful fakes.

Meanwhile, the animal's skin was subjected to careful analysis by Dr. Georg Shaw, who found no traces of glue or other fastening of parts on it. He recognized the remains of the animal as real and in 1799 gave its first scientific description. This is how the unusual animal received the name Ornithorynchus paradoxus, which means “beast with duck feet and beak.”

But it was not enough to give the unusual creature a scientific name. In addition, it was necessary to find a place for it in the taxonomy of the animal world.

Since the animal was covered with fur, no one doubted that it was a mammal. The German zoologist John Friedrich Blumenbach decided to classify it as an edentate; as a rule, they included all animals that did not fit into the classification.

In 1802, two specimens of platypus arrived in England in alcoholic form. One of the animals was a female, but upon closer inspection, she had no mammary glands! In addition to such an incredible property, “water moles” had a combined anus and reproductive passage, like birds and reptiles.

In the end, the English anatomist Home proposed to classify platypuses in a separate class of classification, which soon included another animal discovered in Australia: the echidna, whose elongated muzzle also resembles a beak.

Matters became even more complicated when rumors began to emerge from Australia that the platypus was laying eggs. This fact confirmed Lamarck’s opinion, according to which monotremes are the ancestors of mammals and are close in many ways to birds and reptiles.

In 1824, another surprise: the German scientist Meckel discovered mammary glands in the platypus! But an animal that lays eggs cannot have mammary glands! Nevertheless, they were there. In 1832, Australian naturalist Lieutenant Mole discovered that the mammary glands of the platypus produce milk. It was only in 1884 that a valid method of reproducing and feeding the offspring of platypuses was established. So surprising to everything scientific world An animal has been found that simultaneously lays eggs and feeds its young with milk.

Once again the rule was confirmed: “impossible” animals can exist in nature.

Bunyip

Who is he bunyip?

Up to the present day, the bunyip has served as a symbol of everything mysterious and terrible that the imagination of a colonist who found himself on an unfamiliar continent could imagine.

It seems to me that the word “bunyip” in the Aboriginal language meant everything that could not be explained using familiar concepts. Similar to our word "demon".

It can be assumed that when asked by white people which of the unknown animals committed this or that atrocity, the Australians answered that it was the work of a bunyip or that it crossed their path.

The strange thing is that this mystical creature, endowed with such powerful abilities, was embodied in the image of not only a specific, but also a rather ordinary animal. True, unknown to science.

The first mention of it dates back to 1801. French mineralogist Charles Bailly, a member of Nicolas Baudin's expedition, and his companions left the bay, which they christened after their ship, to go as far as possible into the unfamiliar continent. Suddenly they heard a devilish roar from the reed thickets of the Swan River, more terrible than the roar of an angry bull. In panic, the colonists fled to the shore, deciding that in the swamps of the new continent there was a monster of incredible size.

Later, researcher Hamilton Hume confirmed the existence of a water monster, but curiously, his evidence refers to an area located in the opposite part of Australia. In Lake Bathurst, he observed an animal that looked like both a manatee and a hippopotamus. Scientists of the Australian Philosophical Society immediately promised the researcher to reimburse all expenses if he managed to obtain the carcass of this animal. But Hume could not do this.

Rumors of this kind came from different parts of the continent, especially from the southeastern regions.

Lieutenant V. Breton wrote: “They say that in Lake George there lives a species of seal that has supernatural powers.”

By the middle of the 19th century, the legend of the bunyip was quite firmly established throughout the continent. Who hasn’t been worried about the mysterious beast, and what kind of miracles have been attributed to it! In 1846, a fragment of a skull was found near one of the tributaries of the Murray, which separates Victoria from southern New Gaul, and was sent to the naturalist W. S. Macleay as the “head of a bunyip.” The scientist concluded that the skull belonged to a foal. In London, a specialist in the field of comparative anatomy, Professor Richard Owen, examined the sample and decided that it was a fragment of a cow’s skull.

One of the experts was mistaken, and since the animal was never identified, it can be assumed that both were mistaken. Unfortunately, the valuable evidence mysteriously disappeared.

In 1848, a dark-colored animal with a head resembling that of a kangaroo was spotted on the Emeralia River. He had Long neck, thick growth on the head and a huge mouth. According to local residents, it was a bunyip who was waiting in the water for his next victim.

In 1872, on Lake Burrumbit, a large animal approached the boat, so that all its passengers rushed to the other side in fear and almost capsized into the water. The beast was described as a water dog. His head was round and devoid of ears.

In 1875, near Dalby in Queensland, a seal-like creature was seen sticking out of the water. It had a double but not symmetrical caudal fin.

Moreover, some water monster was registered in Tasmania, that is, outside the Australian continent.

The construction of the Waddaman Dam and all sorts of changes in environmental conditions caused by the construction of the Great Lake Power Plant did not get rid of the omnipresent water demon. His appearance was celebrated here until recently.

Common seal or new marsupial?

With plenty of evidence of a water-dwelling, short-haired pinniped with the head of a dog and flattened ears, it is difficult not to assume the existence of some kind of freshwater seal.

Along sea ​​coast Australia and Tasmania are home to many species of pinnipeds. For example, sea dog (Otaria), leopard seal (Leptonyx), sea ​​Elephant(Mirounga). But can these animals get deep into the continent?

Theoretically, they can. There is, after all, a species of seal that is never found in the seas. In addition, it has been established that seals sometimes penetrate into the interior of Australia along the Murray and its tributary, the Darling. Dr. Charles Fenner mentions a case in which a seal was killed at Conargo, near Southern New Gaul, 1,450 kilometers from the mouth of the river. In Shoalhaven in 1870, a leopard seal was shot and an adult platypus was found in its stomach, causing G. Whitley to remark: “A bunyip swallowed a bunyip!”

Thus, it has been established that pinnipeds can cover significant distances in fresh water. Perhaps they could also make short journeys overland. It is noteworthy in this regard that most often the appearance of the water demon is recorded in the southeast, that is, in the territories of the basins of the two largest rivers in Australia.

As for the heartbreaking screams coming from the reeds, they could not belong to a pinniped, but to a bittern (Botaurus poiciloptius). By the way, she owes her local name “Murray bull” to her voice.

However, the appearance of a water demon is sometimes confined to places that no pinniped could reach, even if they wanted to. Therefore, Australian scientists prefer more original hypotheses.

“It is assumed,” writes Wheatley, “that we are talking about a marsupial similar to an otter that has survived to this day.”

Why shouldn't our demon be an aquatic marsupial? And are Aboriginal legends related to the recent existence of Diprotodon, which is believed to have inhabited the rivers, swamps and lakes of the mainland?

Rabbits the size of rhinoceros

Gold miners scattered throughout sandy deserts the western plateau and the thorny bushes of the central lowland - practically unexplored areas - they encountered large animals that looked like rabbits.

Such reports arrived so regularly that they finally attracted the interest of scientists, among whom was the famous Australian naturalist Ambrose Pratt. He first asked himself the question: were the three-meter rabbits diprotodons, huge marsupials that were considered extinct? After all, before they were in large quantities were found on the Nullarbor Plain until increasing drought turned a large part of the mainland into desert. Their skulls found reached a length of one meter. It was even reconstructed appearance Diprotodon. These extinct marsupials are credited with the habits of a tapir: they must have led a semi-aquatic lifestyle among the lush vegetation that covered the continent at the end of the last glaciation, that is, from twelve to thirty thousand years ago. The drought, which devastated vast territories like leprosy, drove diprotodons from the mainland.

Of course, the huge herbivore initially found refuge in oases that resisted drought. As they dried out, the diprotodon herds moved on to the next source of water.

In 1953, Professor Reuben Stirton of the University of California discovered a veritable diprotodon cemetery in northwestern Australia, containing between five hundred and a thousand perfectly preserved skeletons. It is believed that a herd of these animals gathered at the site recently dry lake, covered with sun-hardened crust. Under the weight of the herd, the crust could not stand it, and many animals got stuck in the wet mud.

Even if they completely disappeared several thousand years ago, they must have been discovered by the first Australian Aborigines.

Van Yennep believes that oral transmission of information cannot last for any long time, while rumors of animals described as similar to Diprotodon continue to circulate among the aborigines.

After all, Australia was not completely deprived of water. Otherwise, the fate of the “giant rabbits” would have befallen other herbivores, as well as the predators that fed on them. There remained a sufficient number of lakes, streams and swamps on the mainland, near which, like other representatives of the Australian fauna, diprotodons could continue to exist.

Despite relatively frequent sightings, Australian hunters chasing feral Asiatic buffalo across the grasslands are unable to capture the presumed diprotodon. According to them, animals have the incredible ability to suddenly disappear from sight, leaving only a cloud of dust in place...

Bernard Euvelmans
Translated from French by Pavel Trannois

The fauna of Australia is unique; there are no monkeys here, and you will not find ruminants or pachyderm mammals. The continent is dominated by marsupials, the world's only representative of wild dogs, a turtle with a long neck like a giraffe, and many other amazing creatures.

1. Echidna

This small animal, covered with needles and with a long proboscis nose, is the only representative of the echidna genus. The echidna is a marsupial, but only it and the platypus lay eggs, which makes them even more unique. It's amazing how the echidna bears its offspring. The female lays a pea-sized egg and then places it in a pouch on her belly. How she does this is still unknown; after 10 days, the baby hatches in the pouch.

1. Kangaroo

Who doesn't know kangaroos!? Everyone knows kangaroos. An amazing Australian animal with large, muscular legs and a strong, long tail. The kangaroo is the only large animal that uses jumping as a method of movement. In nature, there are only 3 types of kangaroos: western and eastern gray, western red. Other species are wallabies, quokas and kangaroo rats, all of which are related.

1. Koala

The koala is a herbivorous marsupial, a relative of wombats. For a long time she was considered a bear, but she has nothing to do with bears. The koala feeds exclusively on eucalyptus leaves and shoots; it has no competition in gastronomy. Other animals avoid the plant, which is high in toxic phenolic compounds and hydrocyanic acid. The unique microflora of the digestive tract allows the koala to neutralize poisons.

1. Wombat

The wombat belongs to the family of two-incisor marsupials. Quite large, reaching a weight of 40 kg. Wombats live in burrows they dig and eat plant matter. The back of their body is extremely hard due to thick skin, bones and cartilage. Something like a shield protects the animal when attacked from behind.

1. Dingo

The dingo's pedigree is full of mysteries. According to recent research, this dog may not be native to Australia. Scientists believe that it was brought to the continent by the first settlers from Asia about 4,000 years ago. Secondary feral dogs found in rich nature Australia has everything it needs to survive: plenty of game and a complete lack of competition.

1. Platypus

After the discovery of platypuses, for another 27 years scientists did not know which class to classify the animals into. But a German biologist discovered mammary glands in them, and platypuses were classified as mammals. Every year, platypuses go into hibernation, which lasts -10 days, and then begins mating season. By the way, the beak of the platypus is soft and covered with skin, and not hard as many people believe.

1. Possum

Not to be confused with possums! One of the most interesting gliders is the sugar glider or pygmy flying squirrel. Because of the animal’s habitat, it is also called the Australian marsupial flying squirrel. But the possum is only partly similar to a squirrel.

1. Bilby

He's the same rabbit bandicoot- another representative of marsupial mammals from sunny Australia. Bandicoots have become rare and are strictly protected. They feed on insects and larvae, various roots, bulbs, small lizards, seeds and mushrooms.

1. Australian snake-necked turtle

This turtle hides its head under its shell not as usual, pulling it in, but laying it to the side. grows up to 30 cm. Against the background of the dark color of the head and shell, the golden-yellow iris of the eyes stands out clearly.

1. Marsupial anteater or numbat

Unlike most marsupials, the females of this animal do not have a pouch. After 2 weeks of pregnancy, the babies have to cling to the thick fur on the mother’s belly. At the Nambats short life, low fertility, delicate offspring and many enemies, so their range is seriously reduced. These are marsupials without a pouch.

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

Subclass oviparous mammals represented by only one order - monotremes. This order unites only two families: platypuses and echidnas. Monotremes- the most primitive living mammals. They are the only mammals that, like birds or reptiles, reproduce by laying eggs. Oviparous animals feed their young with milk and are therefore classified as mammals. Female echidnas and platypuses do not have nipples, and the young lick milk secreted by 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 monotremes because both the intestines and bladder These animals open into one special cavity - the cloaca. Two oviducts in monotreme females also exit there. Most mammals do not have a cloaca; this cavity is characteristic of reptiles. The stomach of oviparous animals is also amazing - like a bird's crop, it does not digest food, but only stores it. Digestion occurs 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 environment like reptiles. Echidnas and platypuses are voiceless - they have no vocal cords, and only young platypuses have toothless - quickly decaying teeth.

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

Origin and discovery of oviparous

Short fact
Platypuses and echidnas are venom-bearing mammals. They have a bone spur on their hind legs, along which poisonous liquid flows. This poison causes rapid death in most animals, and severe pain and swelling in humans. Among mammals, besides the platypus and echidna, only representatives of the order of insectivores are poisonous - the slittooth and two species of shrews.

Like all mammals, oviparous animals trace their origins to reptile-like 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, oviparous animals 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 descended from them, modified and adapted to a terrestrial lifestyle.

Europeans learned about the existence of oviparous animals 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 being played, the sight of this bizarre creature of nature was so unusual for Europeans. And the fact that the echidna and platypus reproduce by laying eggs has become one of the greatest zoological sensations.

Despite the fact that the echidna and platypus have been known to science for quite some time, these amazing animals still present zoologists with new discoveries.

Wonder Beast platypus as if assembled from parts of different animals: its nose is like a duck’s beak, its flat spade tail looks like it was taken from a beaver, its webbed feet are similar to flippers, but equipped powerful claws for digging (when digging, the membrane bends, and when walking, it folds, without interfering with free movement). But despite all the seeming absurdity, this animal is perfectly adapted to the lifestyle that it leads, and has hardly changed over millions of years.

The platypus hunts small crustaceans, mollusks and other small aquatic life at night. Its tail-fin and webbed paws help it 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 underwater with the help of its sensitive “beak”. This leathery “beak” contains electroreceptors that can detect weak electrical impulses emitted by aquatic invertebrates as they move. Reacting to these signals, the platypus quickly finds prey, fills its cheek pouches, and then leisurely eats what it has caught on the shore.

The platypus sleeps all day near a pond in a hole dug with powerful claws. The platypus has about a dozen of these holes, and each has several exits and entrances - not an extra precaution. To breed offspring, the female platypus prepares a special burrow lined with soft leaves and grass - it’s warm and humid there.

Pregnancy lasts a month, and the female lays one to three leathery eggs. The mother platypus incubates the 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. Female most spends time lying on its back and only occasionally leaves the hole to feed. When leaving, the platypus seals the cubs in the nest so that no one will disturb them until she returns. At 5 months of age, mature platypuses become independent and leave the mother's hole.

Platypuses were mercilessly exterminated for 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 doesn’t look like it 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 pouch- a pocket on the belly where she places the egg. Although the female raises her cubs in a comfortable hole, she can safely leave it - the egg or 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 pouch, but for about 5 more months it lives in a hole under the auspices of a caring mother.

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

wedding ceremony

From May to September, the echidna's mating season begins. At this time, the female echidna receives special attention from the 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 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 earth 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 hole. The winner of the tournament receives the favor of the female.

The platypus is an amazing animal that lives only in Australia, on the island of Tasmania. This strange miracle belongs to mammals, but, unlike other animals, it lays eggs like an ordinary bird. Platypuses are oviparous mammals - rare species animals that survive only on the Australian continent.

History of discovery

Strange creatures can boast unusual story their discoveries. 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 by 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 an otter, and a nose like an ordinary domestic duck. Such a beak looked so ridiculous that scientists even shaved the hair on the face, believing that Australian jokers had sewn a duck nose to the skin of a beaver. Finding no seams or traces of glue, the pundits simply shrugged their shoulders. No one could understand where the platypus lived or how it reproduced. Only a few years later, in 1799, the British naturalist J. Shaw proved the existence of this miracle and brought the first detailed description a creature that was later given the name "platypus". Photos of the bird beast can only be taken in Australia, because this is the only continent on which these exotic animals currently live.

Origin

The appearance of platypuses dates back to those distant times when modern continents did not exist. 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 recently extinct dinosaurs. Migrating, platypuses settled throughout the continent, and after the collapse of Gondwana, they remained to live on a large area of ​​the ex-continent, which was later named Australia. Due to the isolated location of their homeland, the animals have retained their original appearance even after millions of years. Various species of platypuses once inhabited the vast expanses 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. Particularly difficult was the fact that the creature had a lot of characteristics that are found in birds, animals, and amphibians.

The platypus stores all its fat reserves in the tail, and not under the fur on the body. Therefore, the tail of the animal is solid, heavy, and is capable of not only stabilizing 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 beast is low, barely reaching 32 degrees Celsius. This is much lower than that of mammals. Among other things, platypuses have one more literally amazing feature. These animals can infect with poison, which makes them quite dangerous opponents. Like almost all reptiles, the platypus lays eggs. What makes platypuses similar to snakes and lizards is their ability to produce poison and the arrangement of their limbs, like those of amphibians. The gait of the platypus is amazing. It moves by bending its body like a reptile. After all, its paws do not grow from below the body, like those of 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 animal's head are the eyes and ear openings. They can be found in depressions located on each side of the head. There are no auricles; when diving, it covers its eyes and ears with a special fold of skin.

Mating games

Every year, platypuses hibernate, which lasts 5-10 short periods. winter days. After this comes the mating period. Scientists have recently discovered how the platypus reproduces. It turns out, like all the main events in the life of these animals, the courtship process takes place in 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; platypus children remain only with the female, who herself raises and raises them.

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 carries everything she needs, wrapping her paws around her and tucking her flat tail under. When the shelter is ready, future mom fits into the nest, and covers the entrance to the hole with earth. The platypus lays its eggs in this nesting chamber. 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 wet its fur.

Birth of platypuses

After two weeks of residence, a small platypus appears in the clutch. The baby breaks the eggs with an egg tooth. Once the baby emerges from the shell, this tooth falls off. After birth, the female platypus moves the young onto her abdomen. The platypus is a mammal, so the female feeds its young with milk. Platypuses do not have nipples; milk from the enlarged pores on the mother’s belly flows down the fur into special grooves, from where the young lick it off. The mother occasionally goes outside to hunt and clean herself, while the entrance to the hole is blocked with earth.
Up to eight weeks, the cubs need the warmth of their mother 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 a sexually mature adult.

Platypuses in history

Before the first European settlers appeared on the shores of Australia, platypuses had virtually no external enemies. But their amazing and valuable fur made them an object of hunting for white people. The skins of platypuses, black-brown on the outside and gray on the inside, were at one time used to make fur coats and hats for European fashionistas. And the local residents did not hesitate to shoot the platypus for their own needs. At the beginning of the twentieth century, the decline in the number of these animals acquired alarming proportions. Naturalists sounded the alarm, and the platypus joined the ranks. Australia began to create special reserves for amazing animals. The animals were taken under state protection. The problem was complicated by the fact that the places where the platypus lives must be protected from human presence, since this animal is shy and sensitive. In addition, the massive spread of rabbits on this continent deprived platypuses of their usual nesting places - their holes were occupied by long-eared aliens. Therefore, the government had to allocate huge areas, fenced off from outside interference, in order to preserve and increase the platypus population. Such reserves played a decisive role in preserving the numbers of these animals.

Platypuses in captivity

Attempts have been made to introduce this animal into zoos. In 1922, the first platypus arrived at the New York Zoo and lived in captivity for only 49 days. Due to their desire for silence and increased timidity, the animals never mastered zoos; in captivity, the platypus lays eggs reluctantly, and only a few offspring were obtained. There are no recorded cases of human domestication of these exotic animals. Platypuses were and remain wild and distinctive Australian aborigines.

Platypuses today

Now platypuses are not considered. Tourists enjoy visiting places where the platypus lives. Travelers willingly publish photos of this animal in their stories about Australian tours. Images of bird animals serve hallmark many Australian products and manufacturers. Along with the kangaroo, the platypus has become a symbol of the Australian continent.

The platypus is an extremely strange animal. It lays eggs, has poisonous spurs, detects electrical signals and is completely toothless, but it does have a beak. Since it is not so easy to see a platypus in nature, we have compiled a gallery of photographs of these unusual animals.

When in the late XVIII century, the skin of the platypus was first brought to England, scientists at first thought that it was something like a beaver with a duck beak sewn to it. At that time, Asian taxidermists made a lot of similar chimeric crafts (the most famous example is the mermaid from Fiji). Having finally become convinced that the animal was real, zoologists for another quarter of a century could not decide who to classify it as: mammals, birds, or even a separate class of animals. The confusion of British scientists is quite understandable: the platypus is a mammal, but a very strange mammal.

First, the platypus, unlike normal mammals, lays eggs. These eggs are similar to the eggs of birds and reptiles in the amount of yolk and the type of division of the zygote (which is related precisely to the amount of yolk). However, unlike bird eggs, platypus eggs spend more time inside the female than outside: inside for almost a month, and outside for about 10 days. When the eggs are outside, the female “incubates” them, curling up around the clutch. All this happens in a nest that the female builds from reeds and leaves in the depths of a long brood hole. Hatching from the egg, small platypuses help themselves with an egg tooth - a small horny tubercle on the beak. Birds and reptiles also have such teeth: they are needed to break through the egg shell and fall off soon after hatching.

Secondly, the platypus has a beak. No other mammal has such a beak, but it is also not at all similar to the beak of birds. The platypus's beak is soft, covered with elastic skin and stretched over bony arches formed above by the premaxillary bone (in most mammals this is a small bone on which the incisors are located) and below by the lower jaw. The beak is an organ of electroreception: it picks up electrical signals generated by the contraction of the muscles of aquatic animals. Electroreception is developed in amphibians and fish, but among mammals only the Guiana dolphin, which, like the platypus, lives in muddy water. The platypus' closest relatives, the echidnas, also have electroreceptors, but they, apparently, do not particularly use them. The platypus uses its electroreceptor beak to hunt, swimming in the water and swinging it from side to side in search of prey. He does not use either vision, hearing, or smell: his eyes and ear openings are located on the sides of his head in special grooves that close when diving, just like the valves of his nostrils. The platypus eats small aquatic animals: crustaceans, worms and larvae. At the same time, he also has no teeth: the only teeth in his life (only a few on each jaw) are worn out a few months after birth. Instead, hard horny plates grow on the jaws, with which the platypus grinds food.

In addition, the platypus is poisonous. However, in this it is no longer so unique: among mammals there are several more poisonous species - some shrews, gap-toothed lorises and slow lorises. Venom in the platypus is secreted by horny spurs on the hind legs, into which the ducts of the poisonous femoral glands emerge. Both sexes have these spurs at a young age, but the females soon fall off (the same thing, by the way, happens with the spurs of echidnas). In males, the poison is produced during the breeding season, and they kick with spurs during mating fights. The basis of platypus venom is made up of proteins similar to defensins - peptides of the mammalian immune system designed to destroy bacteria and viruses. In addition to them, the poison contains many more active substances, which in combination cause intravascular blood coagulation, proteolysis and hemolysis, muscle relaxation and allergic reactions in the bitten person.

Platypus venom was also recently found to contain glucagon-like peptide-1 (GLP-1). This hormone, produced in the intestines and stimulating the production of insulin, is found in all mammals and is usually destroyed within a few minutes after entering the bloodstream. But not the platypus! In the platypus (and echidna), GLP-1 lives much longer, and therefore, scientists hope, in the future it can be used to treat type 2 diabetes, in which regular GLP-1 “does not have time” to stimulate insulin synthesis.

Platypus venom can kill small animals like dogs, but is not fatal to humans. However, it causes severe swelling and excruciating pain, which develops into hyperalgesia - an abnormally high sensitivity to pain. Hyperalgesia may persist for several months. In some cases, it does not respond to painkillers, even morphine, and only blocking the peripheral nerves at the site of the bite helps to relieve pain. There is also no antidote yet. Therefore the most the right way protection against platypus poison - beware of this animal. If close interaction with the platypus is unavoidable, it is recommended to lift it by the tail: this advice was published by an Australian clinic after the platypus stung an American scientist who was trying to study it with both of its spurs.

Another unusual feature of the platypus is that it has 10 sex chromosomes instead of the usual two for mammals: XXXXXXXXXX in the female and XYXYXYXYXY in the male. All these chromosomes are connected in a complex, which in meiosis behaves as a single whole, so males produce sperm of two types: with XXXXX chains and with YYYYY chains. The SRY gene, which in most mammals is located on the Y chromosome and determines the development of the body according to the male type, is also not found in the platypus: this function is performed by another gene, AMH.

The list of platypus oddities goes on for a long time. For example, the platypus has mammary glands (after all, it is a mammal, not a bird), but no nipples. Therefore, newborn platypuses simply lick milk from the mother’s belly, where it flows through enlarged skin pores. When the platypus walks on land, its limbs are located on the sides of the body, like those of reptiles, and not under the body, like other mammals. With this position of the limbs (it is called parasagittal), the animal seems to be continuously doing push-ups, spending a lot of strength on it. Therefore, it is not surprising that the platypus spends most of its time in the water, and once on land, it prefers to sleep in its hole. In addition, the platypus has a very low metabolism compared to other mammals: normal temperature his body is only 32 degrees (at the same time, he is warm-blooded and successfully maintains body temperature even in cold water). Finally, the platypus gets fat (and loses weight) with its tail: it is there that, like a marsupial, Tasmanian devil, fat reserves are deposited.

It is not surprising that scientists had to place animals with so many oddities, as well as their equally bizarre relatives - echidnas - in a separate order of mammals: oviparous, or monotremes (the second name is due to the fact that the intestines, excretory and reproductive system they open into a single cloaca). This is the only order of the infraclass cloacal, and cloacal is the only infraclass of the subclass Prototheria. The primal beasts are contrasted with animals (Theria) - the second subclass of mammals, which includes marsupials and placentals, that is, all mammals that do not lay eggs. Protobeasts are the earliest branch of mammals: they split from marsupials and placentals about 166 million years ago, and the age of the oldest monotreme fossil, Steropodon ( Steropodon galmani), found in Australia, is 110 million years old. Monotremes came to Australia from South America, when both of these continents were part of Gondwana.