Nobody knows exactly when this happened, but probably about 2,000 years ago a clever hunter somewhere in North America figured out that if he had a better way to throw a small spear he would improve his chances of eating dinner that night.
He may have taken the bow he used to spin a wooden shaft and make a fire and discovered he could also use the bow to launch the shaft. Thus came the bow and arrow, a new "weapons delivery system" -- and the drive to build a better version was on.
No doubt he soon learned he could use his new weapon to vanquish his technologically challenged enemies, who were still in the spear-and-dart phase, and quite possibly the world's first arms race began.
No one knows how close that scenario is to the real facts, since experts can't even agree on when the bow and arrow was invented, but anthropologists at the University of Missouri-Columbia think they have pretty well nailed down at least part of the story: Soon after the new weapons system was invented, everybody wanted to build a better one.
"We keep tinkering with something, trying to make it better, and I think that's exactly what folks were doing prehistorically," said R. Lee Lyman, chair of the department of anthropology. Lyman and two Mizzou colleagues, Todd VanPool and Michael J. O'Brien, examined more than 1,000 projectile points at three different locations in North America to see how that technology evolved.
In a paper scheduled for publication in the Journal of Archaeological Science, the researchers say their expectations were fulfilled. Bow and arrow technology spread like wildfire across the continent, and with each hunter trying to improve on the critical arrow point, the poor designs fell away and the arrowhead became pretty much standardized.
For one thing, it got a lot smaller than the hefty projectile points used on the spears that were either thrown or launched with an atlatl, a device used to increase the velocity and range of a spear.
All of this might just seem like common sense, but in fact it is hotly debated among experts. The archaeological record is quite murky. The main evidence comes from the points themselves, since wood used for the bow as well as the arrow does not preserve well. And it's difficult to find a precise date for the points, since they don't carry the "date they were minted," as Lyman put it.
Instead, archaeologists date the points based upon the material in which they were found, which normally includes organic matter that can be dated.
But somewhere along the way, someone had to invent the bow and arrow, and it didn't happen just once. It appeared on this continent long after the first immigrants crossed the Bering Land Bridge with their spears, and long before the first Europeans arrived.
Some archaeologists believe stone arrowheads were being used in Africa more than 20,000 years ago. And the mummy of a man, believed to be 3,300 years old, was found with flint-tipped arrows near the border between Austria and Italy.
So why all this effort to nail down the history of the bow and arrow in North America?
"It's just a little problem we thought might be fun to look at," Lyman said.
The researchers studied hundreds of projectile points at three archaeological sites: Verkamp Shelter in central Missouri, which has been used for the past 6,000 years; Mummy Cave in northwestern Wyoming, used for 9,200 years; and Gatecliff Shelter in central Nevada, used for 5,500 years.