What is a koala thinking?
Asleep for twenty of the last twenty-four hours. Unrepentant.
Eucalyptus is the whole explanation. The leaves are low in nutrition and mildly toxic, so a koala spends a great deal of energy detoxifying very little food. Twenty hours of sleep is the budget, not laziness.
They are also particular about which leaves. Of several hundred eucalypt species a koala will eat from only a handful, and the preference is regional enough that a relocated animal may refuse the local trees outright.
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