Australia has perhaps the most unusual (and dangerous) wildlife of any continent, a product of its unique status as a vast island that broke off from other landmasses millions of years ago. Due to this isolation, plants and animals specifically adapted to its climate, independent of what was evolving in the rest of the world. Among Australia’s unique fauna is the adorable marsupial known as the koala, which is only now being studied with more scrutiny as its numbers dwindle.
In Koala: A Natural History and an Uncertain Future, biologist and author Danielle Clode (Voyages to the South Seas) provides a thorough and descriptive backstory of the koala, including topics such as mating, conception, eating and sleeping habits, sensory patterns and anatomical anomalies. With her scientific yet accessible writing style, Clode digs deep into koalas’ evolution, giving examples from fossil findings that show that koalas’ ancestors were likely much larger than their contemporary descendants.
The facts Clode shares are fascinating, such as the reality that, like humans, koalas are “phylogenetically sterile” (lacking in close relatives). We can at least count apes and monkeys as distant cousins, but “ecologically, as well as evolutionarily, koalas really do sit alone on their tree.” She also explains just how integral a koala’s diet is to their survival. Koalas only eat the fibrous, toxic leaves of the eucalyptus gum tree. As a result, their digestive system has evolved in a specialized way, with enzyme-laced saliva and a supercharged liver to remove toxins.
Clode also discusses human encroachment on koala territory, particularly following the colonization of Australia by Great Britain. Diseases that killed the continent’s Indigenous people also wreaked havoc on animals such as the koala, and continue to do so. Koalas have also been hunted, exported as pets and victims of wildfires and other climatic events. All of these things have made koalas vulnerable, and they are now considered an endangered species by the Australian government.
Leaving no stone unturned, Koala makes great strides to advance our knowledge of this largely misunderstood animal.
