The teat then swells, and fills it's mouth, which prevents the body from getting dislodged from it's food source. Koalas have a very slow metabolic rate, because they mostly sit in trees all day. That also allows them to retain food in their Digestive system for a long time, maximizing the amount of energy being able to be extracted. The digestive system of Koalas, also detoxifies the poison inside of the eucalyptus leaves that would kill other animals. It does this by having an enlarged Caecum of the gut, in the Caecum, there is a large bacterial colony, that aids with the leaf digestion.
Koalas move with an awkward gait, on all four legs, and can also run.
In a couple of occasions they have even been spotted swimming, but this is very rare. Koalas are strictly arboreal, living and feeding mostly on eucalyptus leaves. Only time that it comes to the ground, is when it is changing trees. At this time it is preyed upon by foxes and dingoes. Young Joey's are also sometimes preyed upon by large birds of prey.