Why do we need bones and joints?

Why do we need bones and joints? As all of us very evidently understand, they give us shape, structure , stability and helps us to move around. As my son puts it, without bones, we would be like a wobbly jelly. One of the major difference (among many other notable differences) between every species on this earth, is the structure of our skeletal system. From fishes to dinosaurs to animals to humans, the shape of each life on this planet is determined by the way their bones and joints are shaped and aligned.

When life evolved on earth millions of years ago, the skeletal system  evolved at each stage serving different purposes. It is believed that when life first started in water millions of years ago, skeletal system served mainly as store house of minerals (mainly calcium and phosphorus) . As life moved to earth, the skeletal system acquired different characterstics to provide different shape and different advantages to individual species.  Through further refinement, came the ability to move around freely, hunt, survive etc. The skeletal system also acquired characteristics to encase and protect important organs like heart, lungs, nervous system etc and be able to produce important blood components.

As compared to any other species on earth, the skeletal system in humans is more advanced (similar to many other dimensions of life).  The structure of our spine supports us to stand erect and walk on two limbs ( very few  species on earth are able to do this ). Through more refinement of  joints evolved finer skills, like writing, cooking, playing, dancing, etc. It gave us freedom, skills, entertainment and power to be an unique species on earth.