Koala bears are similar in anatomy to the wombat, which is another Australian marsupial. The weight averages about 30 pounds for a male koala bear and 10 pounds for a female. Australian koala bears take advantage of several forms of self-preservation, including extremely sharp teeth and claws, coloring and sound.
Koala bears use their sharp teeth as a defense mechanism against predators of all size. As herbivores, the teeth of a koala bear have evolved to be able to shred the leaves that make up their diets. Kangaroos and wombats have the same evolution of teeth. This shredding ability can also come in as a defense mechanism to shred through the skin layer and injure predators. The teeth have a jagged edge to them at the the bottom of the molars that shreds.
Koala bears have sharp talon-like claws of their front and back paws. These claws are used mainly to quickly climb up trees for food or protection, but the claws can also be used to swipe at predators. Once the koala has its claws out, it can either evade the predator, if it is a ground predator, by going into the trees or defend against the predator by lashing out. The koala bear is very strong, so a blow with bared claws is capable of taking down moderate-size predators.
The gray and white coloring of the koala bear is another tool for protection. This color combination allows them to hide in the treetops away from land predators. When predators look into the treetops, the koala's coloring looks like the sky. The leaves of the trees used as the koala habitat also hide the bear from predators.
Koala bears are usually silent because they camouflage themselves in the treetops that are their habitats. However, the male koala is capable of making an extremely loud call to warn off predators and attract female mates.