The idea of evolution, that people developed overtime from apes or monkeys into the human beings we are today, has long been debated by scientists and theologists alike and now we have more evidence to support the scientist side or the argument. While studying the shoulders of a 3.3 million year old fossilized hominin known as Australopithecus afarensis, scientists found evidence that suggests that it climbed a lot of trees, supporting the evolution theory. Australopithecus afrarensis is a species that is between an ape and and a human. The shoulder blade that was studied suggests this species spent more time climbing around trees than it did on the ground, although it could walk upright on two legs.
The scientists studying the shoulder found that the shape and joint angles matched up closer to those of an ape instead of those of a human being. Bones grow in different ways based on what you are continually doing with them so it is obvious that this A. afarensis was doing a lot of tree climbing. Still there remain doubters with some people saying that they believe this shoulder is just a product of natural genetics, that is that since this species is in between apes and humans that they just have that particular shoulder shape naturally. It is truly a never ending debate.
http://www.the-scientist.com/?articles.view/articleNo/33017/title/Acrobatic-Ancestors-/