Post on marsupials. Animals of Australia. Description, names and features of Australian animals. Marsupials of Australia
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Squad marsupials
(Marsupiala)
Mammals / Marsupials /
Mammalia / Marsupiala /
Order Marsupials (Marsupiala), with the exception of American possums and coenolests, are common on the mainland of Australia, New Guinea and nearby islands. About 250 species belong to this order. Among the marsupials there are insectivorous, predatory and herbivorous forms. They also differ greatly in size. The length of their body, including the length of the tail, can range from 10 cm (Kimberley marsupial mouse) to 3 m (large gray kangaroo). Marsupials are more complexly organized animals than monotremes. Their body temperature is higher (on average - 36 °). All marsupials give birth to live young and feed them with milk. However, compared with the higher mammals, they have many ancient, primitive structural features that sharply distinguish them from other animals. 
The first characteristic feature of marsupials is the presence of so-called marsupial bones (special bones of the pelvis, which are developed in both females and males). Most marsupials have a pouch for carrying young, but not all have it to the same degree; there are species in which the bag is missing. Most primitive insectivorous marsupials do not have a “finished” bag - a pocket, but only a small fold that limits the milky field. This is the case, for example, with numerous marsupial mice, or mouse species. The yellow-footed marsupial mouse - one of the most archaic marsupials - has only a slight uplift of the skin, like a border around the milky field; the fat-tailed marsupial mouse close to it has two lateral folds of skin, which grow somewhat after the birth of cubs; finally, the baby mouse has something that looks like a bag that opens back towards the tail. In kangaroos, the bag of which is more perfect, it opens forward, towards the head, like an apron pocket. 
The second characteristic feature of marsupials is the special structure of the lower jaw, the lower (posterior) ends of which are bent inward. The coracoid bone in marsupials is fused with the scapula, as in higher mammals - this distinguishes them from monotremes. The structure of the dental system is an important classification feature of the order of marsupials. On this basis, the entire detachment is divided into 2 suborders: multi-incisor and two-incisor. The number of incisors is especially large in primitive insectivorous and predatory forms, which have 5 incisors in each half of the jaw at the top and 4 incisors at the bottom. Herbivorous forms, in contrast, have no more than one incisor on each side of the lower jaw; their fangs are absent or underdeveloped, and their molars have blunt tubercles. The structure of the mammary glands of marsupials is characteristic; they have nipples to which newly born cubs are attached. The mammary ducts open at the edge of the nipples, as in monkeys and humans, and not into an internal reservoir, as in most mammals. 
However, the main difference between marsupials and all other mammals is the features of their reproduction. The process of reproduction of marsupials, the observation of which is very difficult, has only recently been fully elucidated. The cubs in the mother's pouch are at first so small and underdeveloped that the first observers had a question: would they not be born directly in the pouch? F. Pelsart, a Dutch navigator, in 1629 first described a marsupial. He, like many later naturalists, thought that the young of marsupials are born right in the bag, "from the nipples"; according to these ideas, the cub grows on the nipple, like an apple on a tree branch. It seemed incredible that a half-formed embryo, hanging inertly on the nipple, could climb into the pouch on its own if it was born outside of it. However, already in 1806, the zoologist Barton, who studied the North American opossum, found that the newborn can move around the mother's body, get into the bag and attach to the nipple. For Australian marsupials, this was confirmed in 1830 by the surgeon Colley. Despite these observations, the famous English anatomist R. Owen in 1833 returned to the already expressed idea that the mother carries the newborn into the bag. According to Owen, she takes the cub with her lips and, holding the opening of the bag with her paws, puts it inside. The authority of Owen for more than half a century fixed this incorrect point of view in science. The embryo in marsupials begins to develop in the uterus. However, it is almost not connected with the walls of the uterus and to a large extent is only a “yolk sac”, the contents of which are quickly depleted. Long before the embryo is fully formed, it has nothing to eat, and its "premature" birth becomes a necessity. The duration of marsupial pregnancy is very short, especially in primitive forms (for example, in opossums or marsupial cats from 8 to 14 days, in koalas it reaches 35, and in kangaroos - 38 - 40 days). The newborn is very small. Its dimensions do not exceed 25 mm in a large gray kangaroo - the largest representative of the detachment; in primitive insectivores and predators, it is even smaller - about 7 mm. The weight of the newborn is from 0.6 to 5.5 g. The degree of development of the embryo at the time of birth is somewhat different, but usually the cub is almost devoid of hair. The hind limbs are poorly developed, bent and closed by the tail. On the contrary, the mouth is wide open, and the front legs are well developed, claws are clearly visible on them. The forelimbs and mouth are the organs that a newborn marsupial will need first. No matter how underdeveloped the marsupial cub may be, it cannot be said that it is weak and lacks energy. If you separate him from his mother, he can live for about two days. Kangaroo rats and some possums have only one baby; koalas and bandicoots sometimes have twins. Most insectivorous and carnivorous marsupials have much more babies: 6-8 and even up to 24. Usually the number of babies corresponds to the number of mother's nipples to which they must attach. But often there are more cubs, for example, in marsupial cats, in which there are only three pairs of nipples for 24 cubs. In this case, only the first 6 cubs attached can survive. There are also opposite cases: in some bandicoots, which have 4 pairs of nipples, the number of cubs does not exceed one or two. To attach to the nipple, the newborn marsupial must get into the mother's pouch, where protection, warmth and food await it. How does this movement take place? Let's trace it on the example of a kangaroo. A newborn kangaroo, blind and underdeveloped, very soon chooses the right direction and begins to crawl straight to the bag. It moves with the help of front paws with claws, wriggling like a worm, and turning its head around. The space in which he crawls is covered with wool; this, on the one hand, hinders him, but, on the other hand, helps: he clings tightly to the wool, and it is very difficult to shake him off. Sometimes the calf makes a mistake in direction: it crawls to the mother's thigh or chest and turns back, searching until it finds a bag, searching continuously and tirelessly. Finding the bag, he immediately climbs inside, finds the nipple and attaches to it. Between the moment of birth and the time when the cub is attached to the nipple, marsupials usually have 5 to 30 minutes. Attached to the nipple, the cub loses all its energy; he again for a long time becomes an inert, helpless embryo. What does the mother do while her cub is looking for a bag? Does she help him in this difficult moment? Observations on this are still incomplete, and opinions are rather contradictory. During the time it takes for the newborn to reach the pouch, the mother takes a position and does not move. Kangaroos usually sit on the tail passing between the hind legs and pointing forward, or lying on their side. The mother holds her head as if she is watching the cub all the time. Often she licks it - immediately after birth or during the movement to the bag. Sometimes she licks her hair towards the bag, as if helping the cub to move in the right direction. If the cub gets lost and cannot find the bag for a long time, the mother begins to worry, scratch and fidget, while she can injure and even kill the cub. In general, the mother is more of a witness to the energetic activity of the newborn than his assistant. Initially, the nipple of marsupials has an elongated shape. When a cub is attached to it, a thickening develops at its end, apparently associated with the release of milk; this helps the baby stay on the nipple, which he squeezes with his mouth all the time. It is very difficult to separate it from the nipple without tearing its mouth or damaging the glands. The baby of marsupials passively receives milk, the amount of which is regulated by the mother with the help of muscle contractions of the milky field. For example, in a koala, the mother supplies the cub with milk for 5 minutes every 2 hours. So that he does not choke on this stream of milk, there is a special arrangement of the respiratory tract: air passes directly from the nostrils to the lungs, since the palatine bones at this time have not yet been fully formed, and the epiglottic cartilage continues forward to the nasal cavity. Protected and supplied with food, the cub grows rapidly. The hind legs develop, usually becoming longer than the front ones; the eyes open, and after a few weeks the immobility is replaced by conscious activity. The baby begins to break away from the nipple and stick its head out of the bag. The first time he wants to get out, he is not allowed to go by his mother, who can control the size of the outlet of the bag. Different types of marsupials spend a different period in the bag - from several weeks to several months. The stay of the cub in the bag ends as soon as it becomes able to feed not on milk, but on other food. The mother usually looks for a nest or lair in advance, where the children live for the first time under her supervision. 
It is believed that the order of marsupials (Marsupialia) is divided into 2 suborders: multi-incisive marsupials (Polyprotodontia) and two-incisive marsupials (Diprotodontia). The former include more primitive insectivorous and predatory individuals, the latter - herbivorous marsupials. An intermediate position between the multi-incisors and the two-incisors is occupied by a little-studied group of coenolests, which some zoologists consider to be a separate suborder. The coenolest group includes one family and three genera. These are small animals that resemble American opossums and are found in South America.
The diversity of the animal world of Australia amazes scientists. It is home to over 370 species of mammals, more than 820 species of birds, 300 species of lizards, 140 species of snakes and two species of crocodiles. And among the insects alone, flies and mosquitoes, more than 7,000 species have been found. But the real stars of the Green Continent are marsupials, of which there are over a hundred species.
"Teddy bear" in the branches of eucalyptus
It will take several volumes to describe the animal and plant world of Australia, so we will focus only on the most curious animals of this continent, which usually arouse the greatest interest. Let's start with the koala, which usually causes a "wave" of real tenderness in children and adults. It's hard to imagine, but this animal was almost on the verge of destruction! A real war with them was launched because of their valuable fur. Fortunately, people stopped in time, and koalas managed to survive to this day.
The world learned about this cute animal, which has long become a kind of symbol of Australia, only in 1798. At first he was mistaken for a South American sloth, and four years later, the koala was considered a rare species of monkey ... Then this animal was considered a bear for some time, and only later it was figured out that the koala is a distant relative of the wombat and much closer to the kangaroo than to the bears. Both the koala itself and all its closest relatives are marsupials.
The Australian Aborigines have a curious legend about the origin of koalas. If you believe him, then once, a very long time ago, all animals were people. There lived at that distant time an orphaned boy Kub-Bor. Although he was sheltered by relatives, he had a hard time living with them. Cub-Bor learned to find his own food in the forest, but there was a constant problem with water: the boy was always thirsty.
Once, when the boy was left alone, he could not stand it and drank all the water stored by his relatives. Frightened, Cub-Bor climbed a tree, on its top he hung the empty vessels. The tree was not tall, but when the boy sang a song, it began to grow and lifted him up to the very clouds.
Returning relatives discovered the lack of water and became very angry. They saw Cub-Bora on top of a tall eucalyptus and began to demand that he come down. The frightened boy refused, so two shamans climbed a tree and threw Cub-Bor down. As soon as the boy's body hit the ground, he immediately turned into a small eared animal, which again climbed to the very top of the eucalyptus.
As you may have guessed, Cub-Bor turned into a koala. From the legend it also becomes clear why the koala never drinks water: the spirit of the boy living in every animal is still afraid that he will be punished for a sip of water.
The koala does not actually go down to the watering hole, he has enough of the moisture that he absorbs with the foliage, especially when it is abundantly moistened with dew or raindrops. By the way, in the language of the natives, the word "koala" means "does not drink."
An adult koala weighs up to 15 kg, the maximum height of the animal does not exceed 90 cm. It's hard to believe, but at birth, the weight of this funny eared is only 5-6 grams. For about six months, a koala baby spends in a mother's pouch, where it grows and becomes overgrown with fur. For about the same time, the grown animal is still in the care of its mother, moving from branch to branch on her back. It is curious that the koala is a big dormouse, the animal spends about 20 hours in a dream, that is, almost all day.
Alas, to see koalas, you have to fly to distant Australia. The fact is that this animal is not in zoos, it is very expensive to keep koalas, because they eat only the leaves of eucalyptus trees, and even then not all, but only certain species. Every day, a koala eats about one kilogram of leaves. A zoo that takes the risk of acquiring a koala will have to bring branches with the foliage of this tree by plane from Australia or grow eucalyptus trees, if the climate allows.
Animal from the coat of arms of Australia
Another prominent representative of the animal world of Australia is the kangaroo - this animal is even depicted on the coat of arms of the country. Now on the continent there are about 60 million of these animals, which are represented by about 55 species. Of these, the smallest is the tree kangaroo, about 50 cm tall, which lives on the branches of trees. We mainly know the red kangaroo - this is just the largest species. The height of individuals reaches 1.8 meters.
Like koalas, kangaroos are marsupials. Females have a skin fold-pocket on their stomach: it is in this bag that kangaroo cubs hatch and live for the first months. They are born very tiny, before the birth of a kangaroo, the female carefully cleans and licks her bag. A born blind and bald baby gets to the bag along the tail and body of the mother, climbs into it and immediately finds a nipple in it. He clings to it, and with strong paws clings to the female's hair so as not to fall out when she jumps.
After three or four months, the cub begins to crawl out of the bag and jump next to the mother. If he feels danger, he jumps straight into the bag head first, in it he turns over and his “journey” with his mother continues. The cub stays in the bag on the mother's stomach for 8-9 months, until it simply ceases to fit in it. An interesting fact came to light relatively recently. It turned out that mother kangaroos can change their cubs! This was discovered by accident when scientists, studying the life of animals, marked their cubs. After some time, all the tagged babies changed mothers and ended up in other people's bags. Scientists believe that this is due to the fact that in case of danger, the kangaroo cub jumps into the bag of the female closest to him, not necessarily his mother, and she simply “forgets” about the “exchange” that has taken place.
Kangaroos are widespread in Australia, they live in forests and savannahs, and some species even in mountainous areas. These animals move by jumping thanks to their powerful hind legs, their speed can reach 45 km / h. In one jump, they can easily cover a distance of 4.5 meters or even more. Representatives of large species of kangaroos can weigh up to 70-80 kilograms. These animals live in groups, their herd can number up to 50 kangaroos or more.
This animal the size of a small dog has a rather creepy name - the Tasmanian marsupial devil. This is one of the rare predators of Australia, which preys on small animals and birds, frogs, and on occasion even catches crayfish. The Tasmanian devil is an example of cleanliness, he does not miss the opportunity to bathe, and after that he enjoys basking in the sun. There was a time when this curious animal was distributed throughout the continent, but now it has survived only on the island of Tasmania.
Why does this animal have such a scary name? His animal received a rather ferocious disposition, black coat color, ear-piercing night cries and a threatening growl. Small in size, the Tasmanian devil manages to take such threatening poses and make such frightening sounds that even large predators prefer to bypass it. He is not afraid to fight, without hesitation enters into battle with a stronger opponent, defeating even large dogs.
The female Tasmanian devil carries her young in folds of skin on her abdomen. This secretive creature spends almost the whole day in thickets of bushes and only at night goes hunting. If you catch an animal while still a cub, it becomes tame quite easily and becomes very attached to a person. Unfortunately, the Tasmanian devils were on the verge of extinction due to a mysterious disease, the first cases of which were noted in 1996. Unless an effective vaccine or other treatment is found, experts say, Tasmanian devils could be extinct within the next two decades.
Ridiculous platypuses
When a stuffed platypus was first sent to England, British scientists thought that their Australian colleagues were just playing them by attaching a duck's beak to a stuffed rat. The platypus is a truly unique animal in Australia. It is a semi-aquatic animal with completely waterproof fur, webbed feet and a duck-like nose. Platypus females lay eggs; these animals arrange their homes in special ditches, digging them on the banks of rivers and streams.
The platypus is considered one of the symbols of Australia, it is depicted on the reverse of the Australian twenty cent coin. Under no circumstances should this animal be handled. The fact is that male platypuses have spurs on their hind legs that secrete a “cocktail” of various poisons. Fortunately, for a person they are not fatal, but their impact brings a lot of pain to a person and causes swelling of the affected limb, the treatment of which can take several months.
The head of this waterfowl ends in a long flat spatulate beak, the body is covered with thick fur, and there are membranes on the paws. The female platypus hatches her cubs from eggs for about ten days, and feeds them with milk. There are usually two eggs, they are enclosed in a soft film shell. Platypus cubs are born blind, they are completely hairless; they lick the milk secreted from the milky pores on the mother's skin. When the babies grow up enough, the mother takes them to the water, trying to accustom them to hunting for small animals.
The platypus spends most of its time in a hole, which it digs near running water. Only in the early morning and late evening he leaves the hole and spends about an hour hunting for small aquatic inhabitants - fish, crustaceans, worms and larvae. Due to the streamlined shape of the body and webbed feet, platypuses move very quickly in the water. Until recently, due to pollution of water bodies, platypuses were considered endangered, but specially created reserves, fortunately, made it possible to solve this problem.
In conclusion, it is worth remembering the echidna, which in Australia is called the "spiny anteater." Echidna is also a marsupial! She lays her eggs in a bag, from which the "hatching" of the cubs occurs. The female echidna feeds them until the age when the first spines appear in the baby. Thanks to these spines, because of which the echidna has practically no enemies in nature, she manages to survive surrounded by potential opponents.
The most dangerous enemies for the animal are the natives, who cook various local dishes from its meat and fat. These animals do not have permanent housing, they spend the night where it is most convenient for them.
In case of danger, echidnas, if possible, burrow a little into the ground, curl up in a ball, exposing thorns at the same time. Such a prickly “delicacy” is not to the liking of many predators, and they retreat without salty slurping. Of course, the natural world of Australia is not limited to all the animals described above, there are many other animals, birds, fish, reptiles and insects that make it up. If, by the will of fate, you find yourself on the Green Continent, you can see many representatives of the exotic animal world of Australia at the Taronga Zoo in Sydney, at the Melbourne Zoo, in the Rainforest in Port Douglas, as well as in various parks on the continent.
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What are marsupials?
When European travelers entered the New World, they often brought with them what seemed strange and new to them. Thus, the South American opossum was brought from Brazil in 1500, and in 1770 Captain Cook spoke of kangaroos he had seen in Australia. No one in Europe until that time knew about such animals - they were marsupials. Marsupials are a separate order of mammals. Their scientific name comes from the Greek word "marsupion", which means "bag".
These animals are distinguished by the fact that after their birth they live and feed, being in a bag on the body of their mother. This is necessary because marsupials are so small and helpless at birth that they cannot take care of themselves. They don't even know how to eat. Even when they grow quite large, still young kangaroos and opossums run to hide in their mother's bag when something frightens them. Judging by the fossils found in the mountains, marsupials were once common in all parts of the world.
Nowadays, almost all of their species are found in Australia and on the islands adjacent to it. The only true marsupial living in the Americas is the different species of opossum. Australian marsupials come in a wide range of forms, from tiny, mole-like, small creatures a few inches long to huge kangaroos. Some of them, like bandicoots, look like rabbits. Others, like wombats, look like beavers. And thylacines (or Tasmanian wolves) look like wolves.
Marsupials can live on the ground or settle in trees like monkeys. Some of the couscous, which belong to the same family as the marsupials, can even fly from tree to tree like flying squirrels. Marsupials eat a very diverse diet. Some of them eat only vegetables, others eat insects or meat, and some even eat everything they can find.
Amazing marsupials
Most of the mammals known to us, such as bison, hedgehog, mole, lion, elephant, wolf and bear, belong to the placental class that inhabit Europe, Asia, Africa and both Americas. Another infraclass of viviparous mammals - marsupials, live mainly in Australia. The earliest marsupial fossils found in Canada date back over 70 million years, which means that their evolution began much earlier.
Scientists still argue about the place of origin of marsupials, suggesting that it could be any of the Americas. After 40-50 million years ago, Australia separated from the hypothetical continent of Gondwana, which united, in addition to it, modern Antarctica, South America, India and Africa, it became, as it were, a huge “island”, the animal and plant world of which began to develop in its own, independent way. In this world, marsupials did not meet competition from other, more highly organized mammals, which led to two consequences.
Opossum
Firstly, marsupials differ in the placental structure of the brain and embryonic development. Secondly, it is precisely due to isolation and lack of competition that the evolution of marsupials led to the formation of many forms adapted to a wide variety of habitat conditions. Most species of marsupials in general structure and way of life resemble placental mammals living in similar conditions in Europe, Africa or America. Although marsupials inhabit mainly Australia and Tasmania, several species live in South and North America, New Guinea and adjacent islands, and some of them were introduced by humans to New Zealand.
marsupial marten
Interesting to know. Marsupials number 80 genera and about 250 species, they consist of two main groups: the opossums of South and North America and the Australian-New Guinean group, whose representatives have a huge variety of appearance and variability in adaptation to different habitat conditions.
Diversity and similarity of marsupial species
Well-known to us kangaroos in their way of life are very reminiscent of herbivorous ungulate mammals such as deer, antelopes and zebras. Philanders and bendicoots resemble a hare in behavior and lifestyle, and bilbies resemble a rabbit. The Tasmanian devil is similar to a hyena, only very small with a long tail. Marsupial flying squirrels are an Australian analogue of ordinary flying squirrels, the marsupial mole looks very similar to the common mole, although it is not related to it.
marsupial bandicoot
Couscous and tree-kangaroos eat, look and behave like small monkeys, and the climbing marsupial flying squirrel can be compared to a lemur. Small marsupial mice and related species resemble our mice and shrews. Rocky kangaroos play the same role in the natural environment of Australia as goats or wild sheep. The wombat is somewhat similar to the South American capybara, and the paws of the swimmer (japok) are equipped with flippers, like an otter, with which it is similar in behavior and living conditions.
marsupial anteater
Little brain. The marsupial brain in relation to the whole body is much smaller than the brain of a placental mammal. This fact is often cited as evidence of a lower level of development and as the reason that marsupials lose out in competition with other mammals brought to Australia by humans. On the other hand, the complex behavior of many marsupials, associated with the structure of the nest or the search for food, does not at all indicate their "stupidity".
Kuzu is an "Australian" squirrel. There are several types of marsupial "cats" and "weasels", and the extinct marsupial wolf hunted in the same way as our European one. There is even a marsupial anteater. The evolution on the island has also led to the appearance of several species that have no analogues on other continents. One of these species is the symbol of Australia - the koala.
marsupial wolf
marsupial bear koala
However, if we consider the fauna of marsupials as a whole, one can find one important feature that distinguishes them from placentals. Even taking into account the recently extinct marsupial wolf and the fossil marsupial tiger, it can be said that very few large predators lived and live in Australia. The largest marsupial predators currently living in Australia are about the size of a cat or a little more.
Short pregnancy and unusual bag
The way of birth and development of marsupials is characteristic and unusual. Pregnancy lasts a very short time, and the babies are born at an extremely early stage of development. Newborn opossums are about the size of a bee, and baby kangaroos are slightly larger than a grain of beans. The baby marsupial is born near the base of the mother's tail, and from here, wriggling like a lizard, it crawls into the bag along a strip of wool that the female has moistened with her tongue.
Sensation. When at the beginning of the 16th century the navigator Piso, who served under Columbus, brought the first opossum from Brazil to Europe, this animal caused a real sensation. Even the King and Queen of Spain stuck their fingers into the bag to make sure there really was a baby inside.
marsupial mouse
marsupial flying squirrel
The bag is formed by a fold of skin on the abdomen. Its depth and closure varies greatly between species, from a barely marked fold in some small marsupials to a watertight pouch of a swimmer. The newborn gets into it and clings to the nipple, which expands and clogs the baby's mouth as firmly as a wine cork clogs a bottle, as a result of which the sucker is attached to the power source. It grows and develops in the bag even after it leaves it - from time to time it returns there, escaping from danger or simply to feed.
marsupial kangaroo
How does the baby get into the bag? There used to be a lot of incredible speculation about how a baby marsupial gets into a pouch. For example, opossums, according to the prevailing version, bred by rubbing each other with their noses. Some time later, the female would stick her nose into her pouch and blow her babies into it. This tale was born, no doubt, due to the fact that the female opossum puts her muzzle into her bag before giving birth and carefully licks it from the inside. She does this, however, for hygienic purposes, and not because small opossums are born through the nose.
Everyone knows that Australia is the world of marsupial mammals. On the smallest continent of the planet, there is simply an amazing variety of these animals. In addition to the well-known kangaroos and koalas, couscous, wombats, marsupial martens, jerboas, rats, mice, anteaters, moles and even wolves live in Australia. Marsupials also live in regions adjacent to Australia - on the islands of New Guinea. But marsupials, although not in such abundance, are also found on the American continent.
As paleontological studies show, even during the Mesozoic, marsupials lived almost all over the globe. Marsupials and other primitive mammals (oviparous) represented at that time the pinnacle of the evolution of the terrestrial animal world. But over time, more developed mammals began to appear - placental animals, which, as scientists believe, replaced marsupials from all continents except Australia and South America, about 20 million years ago. Australia by the time placental mammals appeared was already isolated from the rest of the world, so its animal world remained practically unchanged. But the fate of the marsupials of South America is quite interesting. Here they lived all over the continent by the time the connection between North and South America arose. And it happened about 12 million years ago. North American species began to penetrate into South America, and almost all marsupials, unable to withstand competition with them, disappeared. Only opossums and coenolests remained here.
In the photo: virginian opossum (cubs love to ride on their mother's back)
Possums not only survived, but also populated vast areas of North America, where they thrive to this day. The Virginian opossum, common in North America, is a rather cute animal, about the size of a domestic cat. It lives along the west and east coasts to the Canadian border. Opossums are excellent tree climbers and are predominantly nocturnal. They eat very diversely: from fruits, berries and nuts to small insects, frogs and snakes. These animals do not miss the opportunity to delve into the garbage if they live near human habitation. But the endurance and vitality of the Virginian opossums is beyond praise. They are resistant to the venom of the rattlesnake and some other snakes of the American continent, have excellent immunity and are not susceptible to many diseases, including rabies.
In the photo: a rat-like opossum, a representative of the coenolest In addition to possums, another marsupial lives in the New World, representatives of the coenolest family, but they are common only in South America, in the Andes. Caenolestovye, they are also called rat-like opossums, outwardly resemble mice or shrews. They live in mountain forests no higher than 4,000 meters. These animals are also active at night, and according to the type of food they belong to insectivorous animals. They are not as numerous as opossums.
So, it turns out that their distant relatives live thousands of kilometers from Australia. And opossums are not only preserved, but also actively expanding their range, moving further and further north.
As the name implies, marsupials are called marsupials because of the presence of a certain bag. This is a special fold of skin on the abdomen of an exclusively female individual, in which the female carries her cubs. Mammals possess this method of rearing offspring, most of which, with rare exceptions, live in Australia, Tasmania, New Guinea and adjacent islands.
The first marsupials appeared on the mainland of South America, from there they spread to other continents. Approximately 120 million years ago, evolutionary development divided viviparous mammals into 2 branches according to the method of childbearing - marsupials, bearing offspring in the skin fold, and placental, that is, producing developed offspring thanks to the embryonic placenta. Subsequently, placental animals replaced marsupials from most continents. Marsupials came to Australia 50 million years ago, when South America, Antarctica and Australia were interconnected. After the separation of the Australian continent, a powerful evolutionary development took place, which resulted in the appearance of representatives of all marsupials in Australia, modern and extinct by now.
Complete geographical isolation and various climatic conditions created fertile ground for the conservation and development of the class of marsupials, some of which have survived to this day. Previously, large herbivorous marsupials, the size of a rhinoceros, and large predatory marsupial lions lived in Australia. The independent development of the continent's ecosystem has created a diversity of species that is not inferior to placental ones. Marsupials of Australia live in trees and in burrows, lead a semi-aquatic lifestyle and plan in the air, eat plant and animal food. Some species of marsupials are outwardly similar to placentals from other continents and occupy the same ecological niches, which is an example of convergence, that is, similarities in the evolutionary development of separate groups living in similar conditions.
In Australia, several orders of marsupials are distinguished. The smallest of them (marsupial mice) are no more than 10 cm long with a tail, the largest modern representatives are gray kangaroos, reaching 3 meters. All of them share a number of common features. First of all, this is the presence of a bag, which, depending on the type, opens in front or behind. Cubs are born after a short pregnancy in an extremely underdeveloped state, further development takes place in the mother's bag, where the nipples with nutritious milk are located. A newborn cub crawls into the bag on its own, grabs the nipple and hangs on it. The female, with the help of special muscles, controls the injection of milk into the baby's mouth, since he himself cannot yet suck. The exceptions are marsupial anteaters and some small marsupials, which do not have a bag, and the cubs, hanging on the nipples, are attracted to the mother's stomach with the help of the muscles of a special milky field. In some marsupials, for example, the spotted marten, the bag is not permanent, but is formed only when offspring appear; at normal times it is just a fold of skin. Other important differences between marsupials and placental mammals are the special bones of the pelvis (marsupials) and the distinctive structure of the lower jaw. These features allow paleontologists to identify fossils with sufficient certainty.
Predatory marsupials of Australia: small predatory - mice and rats, medium - jerboas and martens. The largest predatory marsupial of our time is the Tasmanian devil, which lives exclusively on the island of Tasmania. Previously, the largest was the marsupial wolf, the thylacine, which became extinct in the 20th century.
marsupial moles
Marsupial moles are the only Australian marsupials that lead an underground lifestyle. The eyes hidden under the skin are rudimentary, instead of ears there are small auditory openings. The coat is soft and beautiful, the nose ends in a horny shield adapted for digging underground passages. Many aspects of the life of these animals are still not known to scientists.
Marsupial badgers (bandicoots) lead a terrestrial lifestyle, they are small and medium in size from 150 grams to 2 kg. They feed on everything - insects with larvae, small lizards, fruits of trees, mushrooms and roots. There are several varieties in the family, for example, the rabbit bandicoot is a cross between a rat and a hare. They are also called "bilbies".
The only representative of marsupial anteaters lives in Australia - nambat, a rare mammal of small size, weighing up to 0.5 kg, is listed in the Red Book. Very cute animal with thick fur and transverse stripes on the back. Lives in holes or hollows, can climb trees. Differs in sound sleep, similar to suspended animation. Anteaters have many natural enemies, especially foxes.
koalas
Marsupial bears (koalas) are herbivorous mammals that live exclusively on trees. One of the most recognizable Australian animals. Cute charming animals, extremely slow, which is caused by the consumption of low-protein foods. They deftly climb the branches of trees, they can jump from one eucalyptus tree to another. They descend to the ground just to go to another tree, they know how to swim. Koalas have a characteristic feature - on the fingertips there is a papillary pattern, like in humans. Modern koalas have one of the smallest brains among marsupials, while the ancestors of koalas had a much larger brain.
Marsupial herbivorous mammals, digging holes and underground caves with many passages and branches at a depth of up to 3.5 meters. In the animal kingdom of our days, these are the largest mammals, spending most of their lives underground. Outwardly, wombats look like small bears, about 1 meter in size and weighing up to 45 kg. They have the smallest number of teeth among marsupials, only 12. Natural enemies are only the Tasmanian devil and dingoes. With very thick skin on the back of the body and a kind of shield on the pelvic bones, wombats defend their shelter simply by sticking their butt out at the entrance. Even at the moment of danger, they butt their heads, inflicting serious blows or crushing enemies against the walls of their cave.
Possums
The possum (cuscus) marsupials of Australia include several families of small-sized animals that lead an arboreal lifestyle. The most interesting of these are the Mountain Couscous, which lives in the mountains and hibernates for a long time; The fox kuzu, the only one of its kind adapted to urban life, whose nests can be found under the roofs of houses in the suburbs; a tiny honey badger possum with an elongated proboscis-shaped muzzle feeds on pollen, nectar and small insects, lives on trees, but does not eat honey; marsupial flying squirrels, similar to the placental flying squirrel, with a skin membrane on the sides between the front and hind legs.
The most recognizable Australian marsupials are the kangaroos, a broad family of herbivorous mammals with highly developed hind legs and hopping. Kangaroos - the largest family of marsupials in Australia, includes 50 species and is combined into 3 groups. Kangaroo rats are the smallest kangaroos. Wallabies are medium-sized animals. Giant kangaroos are the largest living marsupials. The image of a giant kangaroo is placed on the coat of arms of Australia.
