score:19
According to wikipedia, the earliest evidence of archery equipment unearthed (from a Danish Bog) was dated about 9000-10000 BCE. Before that, it appears that spear-throwers were generally used for the same purpose.
Considering that the only ancient societies known to make no widespread use of the bow were those in Australia, however people in the north of the continent traded with pacific islander's and learned about the bow from them, however they were never made to be serious tools and were used as toys by their children. you could make an argument that bows were only invented once, and everyone else just saw someone else doing it. I doubt we'll be able to say for sure without more archeological work.