Though they are cute, this fact is unfortunately true. Because the Koala’s diet is so poor (being composed entirely of leaves) their bodies do not have the energies to sustain a large brain, which equates to the Koala being unable to perform unfamiliar or complex tasks. For example, if you were to present a Koala with leaves already plucked from a branch and placed them directly in front of its face flat on a table, the animal would be unable to process the necessary steps in order to eat those leaves because they are outside of the Koala’s experience. The Koala’s brain is 60% smaller than those possessed by similarly sized marsupials, and is nearly completely smooth – typical of very primitive and ancient animals.

In addition to low brain activity, their poor diet means energy must be conserved in the extreme. A koala spends 20 hours a day sleeping, and only 4 minutes on average a day involved in movement.

Post script: The most common cause of death for Koalas is starvation. They have few natural predators, and most females will live to around 16-18 years of age. Because of their rough leafy diet, the grinding teeth of Koalas begin to wear down around 6 years of age. Eventually, these teeth wear away completely and the animal starves. In addition to this, Koalas have very low fat reserves, meaning they need to eat daily. If by a catastrophe they are displaced from their tree (by fire or drought), they will quickly starve to death unless an alternate tree is found nearby.