The Bow is, technologically, an advanced weapon. Even though cavemen made them, It required the concept of amplification.
Since it simply amplifies how far a stick can be thrown.
The concept of components: as parts are separately made and put together for a purpose.
It would have been created after the spear but before most other weapons. Obviously I wasn't there for the creation event, so this info is conjecture(bummer). Anyway The bow was a focused weapon. As such there was the horseman's bow, Footman's Bow, and Hunting Bow. Each one was designed for specific use and each had different range, prescision, and power. The compound bow was a later improvement on the manufacturing of the bow that further maximized the bow's potential.
Previous advancements were achieved through arrow development. Different head types, shaft lengths, and feathering. It is suggested to train the most basic bows first and then move up to your prefered bow.
The skills developed are eye/hand coordination, breath control,and the "perfect strike". The perfect strike skill is often refered to as the "most appropriate strike" or "Harmonious strike" for this moment. It refers to the skill of waiting for the right moment to strike so that the strike (whatever it may be) will have the most effectivness possible. As such, Archery is a valued skill to Dragon, Snake, and almost any Japanese Style.
The health benefits are mainly muscular and related to the back/spine.