Why did Australopithecines live in trees?

Australopithecus lived mainly in southern Africa. These, different from the rest, animals appeared about 4 million years ago. They spent most of their lives on tree branches for safety reasons. There were many predators and competitors on the ground, and life on the trees was more comfortable for them. They looked like a special kind of monkey. At that time, they did not have human skills and ingenuity, but they could get their food in different ways. They often ate the fruits of the trees on which they live.