Koalas and Their Importancy for Our Ecosycytem

It is important for our ecosystems to maintain Koalas out of the extinction list since they play a vital role in conserving the forests inhabited by them. Because of their strict diet of the eucalyptus they help control the excess vegetation of eucalyptus, reducing the fuels that may lead to fires in Australia when is dry season. Knowing more interesting facts about Koalas will give us an insight of why this Marsupials are important. Kolas are marsupials that can eat pounds of a poisonous plants per day, carry their babies on small pouches that they have n their body until they reach maturity and have been living in this earth for around 25 Million of years. Many of the most unique animals in the world are found in Australia. One of those living there are the koalas that can be found in the eucalyptus forests of southeastern and eastern Australia. Koalas are herbivores and considered to be a mammal. Their scientific name is Phascolarctos cinereus, but most people know them as koala “bear”. This species can live up to 20 years.

The koala is a tree-climbing animal (marsupial) that have a pouch for the development cycle. The eucalyptus tree is really necessary for a koala’s habitat as they use it as food and shelter. They can eat more than one pound a day of eucalyptus. However, the eucalyptus leaf can be really toxic for most animals, so koala’s digestive system needs to be strong to make sure they digest it. Scientifics have found that this is why koalas spend their time sleeping so much as their diet plus the hard work of their digestive system gives them little energy. 

This animal can be seen sleeping between 18 to 22 hours. One good aspect from their diets is that thanks to the leaves they do not need to drink as much water often. Some koalas are so smart that they learn to store food in their pouch. One fun fact about koalas is that they take the smell of the eucalyptus tree as they spend most of their time around it. Koalas give birth to underdeveloped young. Birth occurs just 35 days of gestation, with young lacking immune tissues or organs. Their immune system develops while they are in the pouch, meaning survival during early life depends on immunological protection provided by mothers’ milk.

Today the koala is considered one of the 10 most vulnerable animals by climate change. Decades of hunting due to their fur did not help either to their numbers. And these two last years have not been kind to this animal as the bushfires ravaged most of their habitat. Most koalas need a good amount of space to be healthy and happy. One koala can need as much as 100 trees. Koalas can have other dangers in their environment as predators like dingoes and large owls. And as the spread of civilization and the fires ravage their natural habitat cars and dogs might occasionally kill some of them.

Koalas or koala-like animals first evolved on Australian continent during the period when Australia began to drift slowly northward, gradually separating from the Antarctic land mass some 45 million years agoFossil remains of Koala-like animals have been found dating back to 25 million years ago. The koala is the only extant specie of the marsupial family Phascolarctidae. Fossil evidence identifies as many as 15-20 species, following that divergence of koalas from terrestrial wombats (Vombitidae) 30-40 million years ago which are the closest relatives to koalas.

Interesting facts regarding their genome are that it has more DNA than the human genome. DNA is made from chemical building blocks called based pairs. Humans have about 6.4 billion DNA base pairs, but Koalas have 7 billion base pairs. They have a total of 26,558 genes in total, around 5,000 more than humans. They have a total of 16 chromosomes, differing from the ancestral marsupial 2n= 14. The koalas use extra copies of the gene CYP2C to break down the chemicals the plant Eucalyptus contains, which is mostly toxic to any other animal. The only disadvantage is that they also become more prone of not survive if they get a disease called Chlamydia since the same gene that helps them break down the chemicals in the plants keeps them from killing the microbes that cause the disease. 

Their genes are great for choosing food, it helps them determine the juiciest plant leaves, so they don’t have to drink that much, since they get the water from eating leaves. Genes also are the reason they have outstanding sense of smell, which is beneficial to choose a healthier diet by choosing only between 20 species of eucalyptus from around 600 species so they can eat the once with less toxins and more nutrients for a balanced diet. Koala reproduction is interesting since they are induced ovulators. They have special genes to regulate the ovulation as well as for males the ejaculation and its coagulation to prevent sperm leakage from the female reproductive tract. 

Another interesting thing about the koala’s genome in conjunction with a mammary transcriptome and milk proteome, which enable us characterize koalas milk components. There are four Late Lactation Protein genes tightly linked to both trichosurin and B-lactoglobulin, potentially allowing marsupials to fine-tune milk protein composition across the stages of lactation to meet the changing needs of their young, it also encodes a gene that is a eutherian antimicrobial protein.

By studying the skulls of koala we found that their predecessors lived five to 25 million years ago in the Miocene, an Australian team argues that evolution reshaped the animals faces to enable them to eat the tough leaves while maintaining their specialized communication anatomy. Koalas ancestor extinct ancestors are Litokoala and Nimiokoala. 'The unique cranial configuration of the modern koala is therefore the result of accommodating their masticatory adaptations without compromising their auditory system.' -Mike Archer

The koalas use a communication system which can travel long distances. Researchers hypothesize that the ancient koalas evolved the communication system when the Australian continent was drying out and their habitat was becoming less dense, they were able to maintain communication using this low frequency calls. In order to communicate their skulls evolved to have a larger apparatus in the middle ear. Animals with features most suited to their environment (such as the koala which can digest eucalypt leaves) are more likely to survive and pass their genes onto their offspring. 

Before 1937, koalas were being hunted for their coat. Since most koalas are a gray color, they did not blend into the eucalyptus tree as well, making it easy to be hunted. A variation that could have helped some koalas was having more of a brownish tint to their fur which helps them to adapt to their environment and camouflage from predators, since koalas are not fast to escape otherwise. Natural Selection, the best suited species survive and reproduce, allowed the brownish tint koalas to survive and kept the population alive

To conclude, we can surely say that Koalas are not only vital for the ecosystem in Australia, they are as well very interesting animals with fascinating facts that can be important for science and further understanding on their genes and ancestors can be beneficial for Biotechnology. We need to try to save this animal since they are susceptible and currently are under many dangers that could lead to their ultimate extinction.