What mammal survives solely on eucalyptus leaves?

What mammal is commonly described as surviving solely on eucalyptus leaves? The answer is the koala. Koalas are highly specialised Australian marsupials whose diet consists predominantly of leaves from eucalyptus and related trees.

Eucalyptus leaves are fibrous, low in energy, and contain compounds that are toxic or unpalatable to many animals. Koalas have specialised teeth, digestive anatomy, liver enzymes, and gut microbes that help them process this difficult food.

Koalas usually eat selected species of eucalypts, rather than every eucalyptus species available. Their preferred leaves vary by location and season, and they may occasionally consume foliage from other plant genera. For that reason, “solely” is a simplified quiz description rather than a strict biological statement.

The low nutritional value of their food helps explain their slow lifestyle. Koalas may sleep or rest for up to about twenty hours per day and commonly obtain much of their water from the leaves they eat. Among the listed choices, however, koala is clearly the intended answer.