At Fa-Hien Lena, a cave in the heart of Sri Lanka's wet zone forests, we discovered numerous tools made of stone, bone, and tooth – including a number of small arrow points carved from bone which are about 48,000 years old. The invention of the bow and arrow allowed people to hunt prey at a much greater distance. People no longer had to get within "a stone's throw" of prey which could suddenly bolt and escape. This innovation greatly increased the chances of a successful hunt. Bows and arrows also made it much safer to hunt dangerous prey. If you...