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One of the most popular mammals is the lovable and cuddly koala. Its appearance has given rise to calling them bears, often teddy bears and, although they are not bears but rather marsupials, the name has stuck. Their fluffy ears, large spoon-shaped nose, round body and bright button eyes make them appealing to everyone.

Now existing only in the coastal regions of eastern and southern Australia, they are so enormously different from all other life forms that evolutionists are dumbfounded as to what animal they could possibly have evolved from. Although Koalas are mammals, Order Diprotodontia, they are so different from all other mammals that they are the only members of their own separate family Phascolarctidae, Greek for “pouch bear.” Their hands and feet both look like human hands except the koala’s hand has three fingers and two thumbs, and its feet three fingers and one thumb! (V. and C. Serventy. 1989. Koalas. Chartwell Books p. 10).

Adult koalas weigh about 9 kg (20 pounds), are about 60-78 cm (24-31 inches) long, and have a muscular stumpy tail. They are covered with dense, wooly fur, usually ash gray or chocolate brown in color. Koala’s are nocturnal (active at night), arboreal (live in trees), and herbivorous (feed on plants). They live only in eucalyptus forests, and eat only eucalyptus leaves. Koalas spend up to 20 hours a day sleeping, the rest of their time eating.

As mammals, koalas give birth to live young which they breastfeed. As marsupials (Greek for “little purse”), their young, while still in virtually an embryonic state, climb up into a pouch where most of their development occurs. They suckle their infants with milk in their pouch home during most of their early development (Degabriele. in Gould and Gould. 1989. Life at the Edge. Freeman p. 84). After about six months the young emerge from their pouch to take their place in the koala colony, rarely venturing very far from their birthplace (Lee and Martin. 1990. Natural History August  p. 34).

They live almost entirely on the leaves of just 35 of the about 600 known eucalyptus tree species growing in Australia today (Degabriele, 1989, p. 84). Koalas drink hardly any water but instead obtain their moisture from eucalyptus leaves. The koala’s thermoregulatory pattern is dependent on water from eucalyptus leaves, and for this reason they are potentially able to thrive in most Australian forests. The volatile oils in this tree are highly toxic to most other animals, but the koala liver effectively detoxifies their enormous eucalyptus meals.

The koala body is composed mostly of protein (including their organs, and muscles), but their diet of eucalyptus oils and cellulose is virtually protein-free. The koala must synthesize the protein required for normal functioning from digestible nitrogen compounds in the eucalyptus leaves. Nitrogen is a critical element needed to synthesize amino acids used to construct protein. A more critical source of their protein is from the many microorganisms that live in the koala’s extremely long appendix-like cecum. During normal intestinal movements the koala digests a constant stream of these microorganisms that supply the materials the koala requires to produce the protein required to construct muscle and other protein-based structures.

According to evolutionist Garret Hardin, the challenges of koalas to evolution are many and major. Although the koala is called “a triumph of evolution” by Serventy and Serventy, (1989, p. 10) no evidence exists for its evolution. Scientists do not even know where koalas evolved—they are “one of the mammal mysteries of this southern continent” (1989, p. 9). Until recently the most common claim was that koalas evolved from the wombat 20 million years ago (Lee and Martin, 1990, p. 37). One reason for this conclusion is the wombat’s pouch opens backward to protect its young from dirt—the wombat is a digging animal, and the koala’s pouch is also backward facing—allowing its young to see the ground as its mother travels around.

Koalas are also considered closely related to the kangaroo, also an animal very different from koalas. So far no potential common ancestor has been identified for either the koalas or the kangaroo. The problem is that koalas are even very different from the animals that biologists conclude they are most closely related to. Wombats live in the ground and kangaroos are morphologically very different diurnal animals that live on grasslands. The conclusion from a study of the 12 extinct species of koala is that it may belong to the wombat group, which is also in a group by itself (Cronin. ed. 1987. Koala: Australia’s Endearing Marsupial. Reed Books).

It was once thought that a creature based on part of a skull named Adelobasileus cromptoni unearthed in Texas was the ancestor of marsupials. In 2003, though, “the origin of marsupials was turned on its head when” a nearly complete skeleton of a chipmunk sized animal now named Sinodelphys szalayi was uncovered in China (Jackson. 2007, Koala: Origins of an Icon. Jacana Books p. 5). Although discovered far from Australia, the animal has several marsupial features leading to speculation that S. szalayi is the koala ancestor.

Given such fuzzy evidence for koala evolution, speculation abounds about their possible ancestry. This is why Jackson, when adding his own theory to the mix, stated that the koala “appears to have evolved from a group of marsupials now known as diprotodonts” (Jackson, 2007, p. 14). Instead of evolution, the fossils tell us that the “koala is the only living descendant of an entire marsupial suborder, the Phascolarctomorpha (meaning animals shaped like koalas) … a lonely remnant of a once full crown” (Archer and Hand in Cronin.1987. p. 79).

Fossil finds from both South Australia and Queensland have uncovered jaws and teeth that indicate 12 different koala species once existed. Evaluation of this evidence shows only that loss and extinction has occurred, and zero evidence of evolution. This evidence has made the problem of the animal’s evolutionary history more difficult:

But, if we consider also the extinct groups of marsupials, the picture becomes a little less clear. The diversity of koalas as well as primitive members of other marsupial groups inclines us to be far more cautious about interpretations of the precise relationship between koalas and wombats (Archer and Hand. 1987, p. 79).

The fossils show no hint of evolution, none, only extinction, and degeneration of the  koala variety (Philips. 1990. Koalas: the Little Australians We’d All Hate to Lose. Australian National Parks and Wildlife Service p. 7) So different are koalas from any other animal that, although some minor traits of the extinct koalas, such as teeth, support the wombat theory, other fossil evidence suggests that koalas “form a third independent order of diprotodont marsupials” (Archer and Hand. 1987, p. 81). As Stahl admits, the origin of the koala, and all of the phalangeroid marsupials for that matter, “is far from solved” (Vertebrate History: Problems in Evolution. Dover Publications 1985, p. 441). Evidence cited for koala evolution includes its putative “vestigial” tail. Actually, its thickly padded tail is designed to aid koalas when sitting in trees—which they do for most of their entire lifespan.

Koalas—and all marsupials—are clearly not more primitive then mammals, just very, very different. So advanced is the koala that Serventy and Serventy state it is a triumph of evolution, able to survive and thrive on a diet of gum leaves, not the most nutritious of plants. Its “solution … has made the koala the success story of Australian forests” (1989. p. 10)

In conclusion, the precise relationship of koalas to vombatiform marsupials or any other possible ancestors, remains a mystery (Archer and Hand.1987, p. 82). Furthermore, the most primitive species is not necessarily the oldest in the fossil record, a major problem for evolution theory (Archer and Hand. 1987, p. 91).  Koalas are an enigma for evolution, but not for creationists. They are a success story, not of evolution, but of ingenious intelligent design.

Jerry Bergman
July 2010

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