Koalas

Koalas are sometimes called Koala Bears. They are not bears in any way; they have more in common with kangaroos and even more in common with wombats. Their large head, overly furry ears, semi forward facing eyes, large nose, brown to grey fur, stout tailless body, and claws give it a certain teddybear like appearance. As an herbivore, koalas can eat a wide variety of parts of plants. They have been seen living in Acacia, Allocasuarina, Callitris, Leptospermum, and Melaleuca trees. But they are highly specialized to eat eucalyptus leaves. And out of over 600 species of Eucalyptus, Koala strongly prefer only 30 of those. This preference seems to be driven by the high protein an high water content of the leaves. Koalas do not often drink water. But they do need too drink water occasionally and it is a myth that they don't. Eucalyptus leaves contain cyanide to varying degrees per leaf, branch, and tree; too which the Koala has some degree of tolerance as their livers can process some of it but the Koala is not completely immune. It uses it's nose to find the safest leaves. It will store more toxic leaves in its cheek pouches to consume slowly later. A Koala's complex digestive tract will also sort and store the more toxic pulp to be digested at a slower rate or to be regurgitated for similar effect. Eucalyptus leaves contain minimal energy so Koalas tend to expend very little on physical activity and also very little energy is wasted on thinking. Koalas have the worst brain to body mass ratio of any marsupial or mammal. Experimental evidence suggests that a Koala does not know what a eucalyptus leaf is if the leaf has been separated from the tree. A Koala abdominal pouch is backwards from many other marsupials. It can not clean its pouch like many other marsupials do. The often downward direction of the opening allows foreign materials to exit more easily, but it is a filthy place most of the time. During breeding season, an antibacterial secretion will flush out the filthy pouch and young Koala will eventually bring an antibacterial coating with them. When a baby Koala leaves the pouch, it will continue to ride on its mothers back for about 12 months.