|Koala doing what he does best. Photo: Sanjay Ach|
However, this lazy lifestyle is one of necessity. Koalas almost exclusively eat eucalyptus leaves which are extremely low in protein and nutritional content. Therefore, the koala has evolved with a very slow metabolism and requires long periods of inactivity to properly digest and extract the maximum amount of nutrients from the leaves they consume. Of the four hours or so that they are awake each day, koalas spend two hours eating. The rest of the time is spent curled up on a tree branch napping the day away.