The Orang Utan: Supporting the great weight
At the same time, their size does seem to be something of a handicap to them. Branches break under their weight. Often they are unable to get fruit they relish because it is hanging far out on a branch that would never support them. Moving from tree to tree can also cause problems. There is little difficulty if substantial branches from each tree overlap, but that is not invariably the case. The Orang Utan deals with that problem either by reaching out until he can clasp a stout branch, or by rocking the tree that he is in until it bends over far enough for him to climb across.
Ingenious though these techniques may be they can hardly be reckoned easy or swift. Indeed, sometimes an old male gets so large that he apparently finds the whole process too exhausting and whenever he wants to travel any distance, he comes down and lumbers across the forest floor. There is also evidence that the arboreal way of life is fraught with danger for the Orang Utan. A study of adult skeletons showed, rather pathetically, that 34 percent had, at one time or another, broken their bones.
Female Orangutan and baby in Perth Zoo
