Koalas are cute creatures that can often be seen on tree branches. However, simple at first glance, creations have many interesting features and traits inherent only in their appearance.
Origin of the species
Scientists still cannot come to a conclusion when exactly these animals appeared. Some believe that their distant ancestors lived during the late Miocene: 11-5 million years ago. Others believe that the first koalas began to inhabit Australia in the Pliocene: 5-3 million years ago.
Since the herbivore practically has no kinship with other animals, despite some common features with bears, it is not possible to more accurately establish their ancestors and evolutionary features.
Discovery story
Since these animals live in Australia, history experts may suggest that Tim Cook, the famous traveler who discovered these lands in 1770, was the first to discover them, after which he set up expeditions several more times. However, the seafarer did not meet with koalas due to banal bad luck. Since animals spend all their time on trees and move little, travelers who did not even think about looking at eucalyptus branches lost sight of them.
Humanity first became acquainted with these animals in 1802, when the governor of New South Wales received a parcel from a Barallier soldier. Inside the box, he found an alcoholic carcass of an unknown creature. This finding aroused great interest among scientists, and they began to study it. However, a year later, people personally met with koalas, and after some time a large article was published in one of the scientific journals describing this animal in detail.
Interesting fact: Despite the fact that koalas live only in Australia, their habitat covers a million square kilometers.
For several years they were considered close relatives of the wombat, writing in one form. This is not surprising, since these animals are similar in appearance and are double-edged marsupials, which misled the zoologists. But with a more accurate study of koalas, they were singled out in a separate form.
For a long time, these herbivores were found in humans only in New South Wales. But in 1855 they were spotted in Victoria. And already in the XX century, in 1923, they came across in Queensland.
Why is a koala so called
The name of the animal is based on the Darak word gula, which translates as “gluttony”. Given that koalas are constantly sitting on trees and chewing on eucalyptus leaves, it was not chosen by chance. The word was quickly redone in koola. After some time, the second vowel “o” changed to “a”, and the familiar koala appeared.
In 1817, the German paleontologist Goldfus added the word cinereus to the name, which means “ashen”. Until now, the official name of the species is considered cinereus koala.
Interesting fact: at that time, people believed that koala in one of the European dialects means “does not drink,” but later this theory was refuted.
After the discovery of Australia by James Cook, local Aborigines began to willingly interact with the rest of the world and communicate with sailors. Thanks to this, some of them quickly learned English. And the English-speaking inhabitants of the tribes began to call animals koala bear, which translates as “koala bear”. The phrase quickly flowed to other countries, where many residents still use it, not even suspecting that this is a mistake.
Description, appearance and features
Outwardly, koalas are some of the funniest animals. They have a large head in relation to the body, a nose of impressive size and wide ears sticking out in different directions. On such a face, small bead eyes set far apart look especially funny.Despite the bulging belly and small body size, the animals have a strong and stocky body, otherwise they would not be able to spend their whole lives on trees, clinging to branches.
The size of an individual depends on where it lives: in the southern or northern part of Australia. Koala living in a warm climate grows up to 85 cm and can weigh up to 15 kg. Inhabitants of the northern lands, due to environmental conditions, develop worse and can only stretch to 60 cm, and the mass often reaches the mark of 5 kg.
Males grow larger than females, but have smaller ears. Their stomach is capable of secreting secretions to attract females. Females in front have a fold bag for carrying cubs. There are mammary glands.
Koalas have a powerful jaw. The total number of teeth is thirty. The front ones are sharp incisors, thanks to which it is easy to tear the dense leaves of eucalyptus. On the edges are chewing teeth that can quickly grind food into porridge.
Paws of animals are long and strong. The palm of the forelimbs consists of five long fingers, and when the koala grabs the branch, she puts two on one side and three on the other to provide the most solid grip. The hind legs have pronounced thumbs that do not have nails, as well as four more toes with small claws. They are also used to grip a tree trunk.
Interesting fact: pads on the limbs of koalas have unique fingerprints, like those on people.
Most of the herbivore's body is covered with thick, soft gray fur. Its length in adults reaches 3 cm. The inner part of the legs and stomach are covered with white hair, it is also on the face of the animal, forming a beard and mustache. At the back of the koala there is a small tail resembling a bear in shape, but it is rather difficult to examine it with the naked eye.
Despite the large head, herbivores have a very small brain. Zoologists suggest that this is due to the poor diet of their diet, because of which the body receives only certain vitamins and nutrients.
Where does koala live?
Koalas live only in Australia, in areas where eucalyptus trees grow. Initially, they inhabited the southeastern part of the mainland, but later some individuals moved west, towards the islands of Kunguru and Magnitny. To increase the number of species, people still help them settle in Australia, transporting animals from Victoria to other lands with favorable conditions.
Now herbivores are found in all areas of the country where there is eucalyptus. Because of this, they cover a rather large area, but their density is not numerous. There are sites of hundreds of square kilometers in which only one koala lives. But there are also lands where up to eight individuals can huddle on one hectare.
The most favorable conditions for these animals are forests with a humid warm climate.
How much koala lives
In vivo, the koala is able to live 13-18 years. Thanks to a measured lifestyle, she practically does not spend energy and does not wear out her body. Under artificial conditions, being under close human control, the herbivore can live up to 20 years, because it can behave even more passively.
Is a koala a bear?
Despite the fact that Australians and local Aborigines called animals “koala bear”, this is a mistake. Koalas are not related to bears. Although they have some resemblance to them, they have nothing to do with them. However, when scientists established this, the phrase koala bear is so firmly established in everyday life that it still cannot be eradicated. So far the kinship of koalas has been proven only with wombats and kangaroos, but even with these animals they do not have a strong genetic connection.
What does koala eat?
In the diet of these animals there are exclusively eucalyptus trees.There are enough of them in Australia every year, so there is plenty of food for the herbivore, even though ring-tailed couscous and marsupial flying squirrels also feed on eucalyptus. During the meal, koalas carefully chew the leaves, washing them into porridge. They do not swallow some flesh, but leave them behind the cheeks to refresh themselves later.
The liver of animals is very powerful. Since eucalyptus leaves contain poison, the organ works continuously, protecting against poisoning. Due to the good sense of smell, koalas are able to choose those leaves that contain the least toxic substances. By autumn, the concentration of poison increases, and then koalas can move to the rivers, since trees grow near the water, in which the poison is formed in such an abundant amount. Of the 600 species of eucalyptus, animals prefer to eat only 30th.
Koalas do not consume other food, because their low metabolism is not able to cope with it. But the fibrous leaves of eucalyptus, rubbed into porridge, the intestine perfectly accepts. Every day, the animal eats 500-1000 grams, the process of eating can take up to 8 hours, after which it immerses itself in sleep for 12-17 hours.
Interesting fact: sometimes koalas can eat land. By this they are trying to replenish the supply of enzymes in the body.
Koalas practically do not drink. While eating eucalyptus leaves, they lick the dew from their surface, and this amount of liquid is enough. However, there are situations when an animal can go down to a pond and drink a large volume of water, for example, in case of illness or during drought.
Features of character and lifestyle
Koalas have a calm character and spend most of their lives in trees. In the afternoon they sleep, and sleep can last up to 20 hours. They fall asleep in a sitting position, clutching tightly on the branches. Having woken up in the dark, the animal begins to eat leaves, after which it again plunges into a deep sleep.
Having a slow reaction, koalas move little, and if their attention is distracting, they can completely freeze for several hours in place, peering at an object. During this period, the beast will be completely motionless.
Despite the slowness, koalas are able to quickly climb trees. And at the sight of danger they can jump from a branch and hide from sight, running away on all fours. The usual speed of movement on the ground at the beast is approximately 4.06 km / h, but increases several times during the run. If it is not possible to hide from the pursuer, the herbivore can scream loudly, although in everyday life it practically does not make sounds.
However, fearful koalas are only in relation to opponents whom they cannot defeat. But if the enemy is not so formidable, they can engage in battle with them, skillfully wielding powerful hands.
Koalas are peaceful to humans. If people do not harm them, the animals willingly go into their hands and allow them to take care of themselves. No wonder in artificial conditions they are able to live much longer.
Social structure
Each individual lives in a separate territory, which is previously marked. Females in most cases are neutral towards uninvited guests appearing on their lands. But if the male sees another koala that has entered his area, then he will certainly attack to displace the enemy.
Even in zoos, being on the same territory, individuals try to stay apart from each other, occupying opposite trees.
Breeding
The female is able to give birth to offspring already at the age of two, but the males finally mature only by the age of four. Childbirth occurs once every two years. For the breeding of koalas, the period from September to February is distinguished. Since there are much more females born in the population, during this time the male visits from 2 to 5 female representatives. To attract attention, he travels through territories, marks trees and makes loud cries.So he is trying to attract the attention of females living nearby. If two males meet, they can join the battle for the attention of the female. The latter, in turn, always chooses a larger and vociferous one.
After the male does his job, he returns to his territory and does not participate in the further education of the offspring. The pregnant female remains in place and leads her usual lifestyle: feeds and sleeps. Pregnancy lasts from 30 to 35 days. Most often, one baby is born, very rarely two.
Interesting fact: A koala cub is born completely bald. Its length is only 1.5 cm and its weight is 5 g.
For the first six months, the child sits in his mother’s bag and feeds on her milk. His body constantly receives nutrients that it uses to increase mass, growth and development of organs. Having gained enough strength, the child crawls out of the bag and begins to get used to the world around him. He spends most of the time on the back of the female.
At about the seventh month of life, a small koala stops drinking mother’s milk and begins to feed on its excrement. The latter are half-digested porridge from eucalyptus leaves. Such a “diet” is necessary so that the animal’s body gradually gets used to adult food and learns to cope with poison. If a child immediately started eating eucalyptus, its fragile liver would simply fail due to a high load. The absorption of maternal waste products continues for a month. When an animal feels that it is ready to eat fully, it ceases to depend on someone in terms of food.
Young females live with their mother for about a year. At this age, they become independent and go in search of empty territories that will settle in. Males, since they develop much more slowly, can be near their mother for two to three years.
Natural enemies of koalas
Koalas have no natural enemies. Since they have been eating eucalyptus all their lives, their coat and entrails are saturated with the acrid smell of this tree. Predators do not attack, because their meat will be tasteless. Naturalists only recorded a few cases when wild dogs attacked herbivores, but predators did this not for food, but out of mischief.
Unfortunately, the greatest danger to koalas is man. People living in Australia regularly cut down hectares of eucalyptus forests, which is why animals are forced to move to new territories. Slow animals also often go on the road, where for reasons only known to them they freeze and stand motionless for several hours, or until a car appears on the way.
Due to the same type of nutrition and obtaining only certain vitamins, koalas have weak immunity. They can get sick literally out of the blue, and among them the following diseases are developed:
- periostitis of the skull;
- sinusitis;
- conjunctivitis;
- cystitis;
- pneumonia.
Sometimes the disease goes harmlessly, and after a couple of days the animal continues to sit on branches and eat leaves as if nothing had happened. But sometimes whole epidemics arise. For example, in the last century, the number of koalas was greatly reduced due to pneumonia. The nose is also a problem place for the herbivore: sinuses are often inflamed, which can turn into a serious complication.
Population and species status
At present, approximately 43 thousand koalas live in Australia under natural conditions. A few thousand more are in reserves. Their appearance has not yet been positioned as “on the verge of extinction,” but over the past decades, the number of representatives has been gradually decreasing.
In addition to regular diseases, the man also had a hand in the sharp decline in the population of koalas. Until the hunting of these animals was prohibited in Australia in 1927, people regularly combed the forests with the aim of bringing home several fluffy carcasses.Koala fur was of great value, because it was made of warm and beautiful clothes. But when it became forbidden to hunt them, the total number of herbivores began to gradually increase.
However, despite the fact that people have ceased to intentionally pursue them, animals regularly encounter forest fires and other environmental factors that impede a comfortable life.
And sometimes koalas themselves become the cause of their problems. For example, in 2015 in Victoria, their numbers became so high that they gnawed most of the eucalyptus trees growing on these lands. Then the state government decided to catch and eliminate 700 individuals. Despite such cruel measures, it helped the rest of the koalas, which have ceased to experience hunger and lack of resources, survive.
How the number of herbivores will change in the future is unknown, but the people of Australia are trying to do everything necessary to protect them. For example, after the infamous Australian fires, the surviving koalas were assigned to nature reserves and other territories so that they could start a new life in a new place. Also, zoologists often patrol large areas, helping animals in need.
Types of Koalas
As mentioned above, koalas are represented by the only species cinereus koala. In animals there is no division into subspecies, despite some external features depending on the place of residence.
Two individuals from different Australian states are very similar at the genetic level, and they have no differences that can be classified into individual species. This, by the way, helps koalas in the settlement of territories. After all, if representatives of these herbivores already live in certain weather conditions, there can be no doubt that other individuals who came from the other end of the mainland will perfectly master here.
