Did you know that it was not until 500 A.D. that Native Americans started using bow and arrow? They started using them, for hunting to be easier and faster, started using the bow and arrow because they saw that bow and arrow was more efficient than the normal spear.
Not only but bow and arrows actually used less material than spears. With time, Native Americans started upgrading, some of the upgrades were: poisoned arrows, small bows, etc.
Fun fact: Spear travel about 120 feet/sec were an arrow can go up to 225 feet/sec. The choice of materials and the design of arrows and the bow were not random. Bows used while mounted on horseback are shorter than the bows used when on foot, due to the weight. While on foot