The 25 Dumbest Animals on Earth

Koala

Our cute cuddly friends from Australia are not exactly known for being the most brainy of creatures. Sure, they look adorable as they sit in trees munching on eucalyptus leaves. However, koalas tend to be operating with little in the way of brain activity. According to some reports, koalas have the smallest brain-to-body ratio of any animal. From a size standpoint, some estimate a koala’s brain being smaller than a walnut.

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