Originally named “koala bear” by English speaking settlers in the late 18th century for its ”bear-like” appearance, it is actually a marsupial whose closest living relative is the wombat. The koala commonly weighs between 11 and 31 pounds (5 and 14 kilograms) and is known for its large furry ears, pouch, long limbs, and its clawed, five-fingered paws. These paws include opposable thumbs and claws, giving koalas a superior ability to grip trees branches. Their fingers also have prints that are so close to humans that they’re nearly indistinguishable under even the most scientific of scrutiny.

Koalas are one of the few species on the planet who behave almost exactly as they are portrayed in popular culture – they spend up to 20 hours a day sleeping in trees, and most of the rest of their time eating eucalyptus leaves (this is believed to be a result of evolving to eat something no other species can or wants to eat. The leaves are toxic to most). This sedentary lifestyle has caused them to have an extremely low metabolic rate, and has caused a shrinkage in brain mass over generations. While its ancestors once had brains that filled their entire cranial cavity, the modern koala’s brain is no larger than a couple of walnuts. It’s the only animal on record with such a greatly reduced brain-mass. Newborn koalas are known as ‘joeys’, and like all marsupials, they spend the first six months of their lives living in their mothers’ pouches, before slowly weening and gaining independence over the following six months. The koala’s range is exclusively in Australia.