As night descends on the eastern coast of Australia, a fuzzy form waddles its slow way across the forest floor. A noise is heard, and with surprising agility the creature takes to the trees. Using its sharp claws and strong muscles, it leaps from tree to tree to find that just-right perch. When a low nasal snort echoes through the trees, its ears twitch. In response, this creature emits a similar sound into the night before proceeding to bite a mouthful of eucalyptus leaves between its sharp teeth.
Silhouetted in the moonlight, the creature resembles a large teddy bear come alive, with its big ears, big nose, soft eyes and softer fur. Then a whiff of eucalyptus is caught up by the breeze. It is clear that this animal is not an animated child’s toy. It is an amazing creation of the Great Designer. It is the koala.
Not at all a bear but a marsupial like the kangaroo, this charming 10-to-20 pound creature adds magnificence to the eucalyptus forests on which it depends for its survival.
A Singular Diet
Eucalyptus leaves, usually the koala’s sole source of food, make up a very high-fiber, low nutrient diet. How does the koala survive on such a diet? Our great Designer has equipped the koalas to conserve energy in several ways. One is by sleeping. Koalas sleep about 75% of the time. Then, they are designed with a very slow metabolism that allows their food to stay in their digestive system for a relatively long period of time. This maximizes the amount of energy extracted from the food. Then, too, the koala has a very long fiber-digesting organ, the caecum, which allows more time for bacteria to break down the otherwise indigestible eucalypti fiber.
As this animal rarely drinks, the koala’s body must absorb as much water as it can from eucalyptus leaves. Notably, the koala’s name comes from an aboriginal word for “does not drink.” Their large noses can detect differences between eucalyptus trees, allowing them to choose those with the highest moisture content. The koala rarely drinks water except if—during a draught—the water content of the eucalyptus leaves is reduced. If necessary, the koala can store harvested leaves in its large cheek pouches and carry them away for future use.
Eucalyptus leaves are extremely poisonous to most animals. Why aren’t koalas “drugged out” on these leaves? Again, our great Designer has equipped the koala to handle this problem. During its slow digestive process, the liver and bacteria in the stomach detoxify the poisonous chemicals of the eucalyptus leaves. (How did the koala evolve this unique process and get it into its genes to pass onto its offspring?)
Although the koala’s system must work hard to survive on a diet made up of solely eucalyptus, it is not without advantages. The scent of the eucalyptus permeates the koalas’ fur, and the strong cough-syrupy scent keeps them relatively free from parasites.
Their thick, eucalyptus scented fur, also protects them from all sorts of weather—their only shelter is that of the tree branches. And while their pear-shaped body makes them adorable in the eyes of humans, it also provides great stability for the koala who spends most of its time sitting in trees. They are well suited for their arboreal life. Their bottoms are extra-furry, a cushion of sorts for all the sitting they do. Their Designer has also given them two opposable fingers on their front paws that act against their three fingers like our thumbs do. This “tool” is ideal for clutching a branch. Koalas are master climbers. Clinging and climbing are as much a part of the koala’s life cycle as the eucalyptus, if not more so.
Female koalas have one baby a year, during the summertime (while it is winter in the USA). About 35 days after mating, a koala baby (called a joey like all marsupial babies) is born. Weighing about 5.5 grams at birth and no larger than a jellybean, blind, earless and hairless, it climbs through its mother’s fur and into her pouch, where it lives and grows on a steady supply of its mother’s milk. After about seven months, the joey emerges and spends the next several months clinging to its mothers back, during which time it is weaned and develops a tolerance for eucalyptus leaves. By the time the next breeding season comes around, joey will have moved to its own tree, not too far from its mother’s.
Koalas are somewhat solitary creatures. Except for mother/joey and mating couples, koalas do not share trees. However, they do live in communities consisting of an area of forest under one dominant male, perhaps a few subdominant males and a handful of female koalas. When searching for its own territory a koala will not only seek out areas with plenty of food and shelter but also (and perhaps more importantly) areas where there are other koalas. Once established, they are sedentary animals, maintaining one area as home all their lifetime of between 13 and 17 years.
With few enemies aside from humans, without drinking, without shelter except that of the trees and their coats, these amazing creatures live their lives in their very specific environment and are uniquely suited to it. How did they do it? How did they adapt themselves to their environment? They are another evidence of our all-knowing, all-powerful Creator.
Like all of us, they are gifted with unique abilities that allow them to survive. Truly they are another incredible and adorable reason to give thanks and praise to our Awesome God, “who does great things, unfathomable, and wondrous works without number” (Job 9:10 NASB).
Sources of Scientific Data in this Article: