Arrowheads are among the most easily recognized artifact in the world; and often the subject of a number of misconceptions. Here are some of my favorites:
Myth Number 1: All triangular stone objects found on archaeological sites are arrowheads
Arrowheads, objects fixed to the end of a shaft and shot with a bow, are only a fairly small subset of what archaeologists call projectile points. A projectile point is a broad category of triangular pointed tools made of stone, shell, metal, or glass and used throughout prehistory and the world over to hunt game and practice warfare. A projectile point has a pointed end and some kind of worked element called the haft, which allowed attaching the point to a wood or ivory shaft.
There are three broad categories of point-assisted hunting tools, including spear, dart or atlatl, and bow and arrow. Each hunting type requires a point tip that meets a specific physical shape, thickness and weight; arrowheads are the very smallest of the point types.
In addition, microscopic research into edge damage (called 'usewear analysis') has shown that some of the stone tools that look like projectile points may have been hafted cutting tools, rather than for propelling into animals.
In some cultures and time periods, special projectile points were clearly not created for a working use at all. These can be elaborately worked such as the so-called eccentrics, or created for placement in a burial.
Myth Number 2: The smallest arrowheads were used for killing birds.
Experimental archaeology has shown that so-called 'bird points'--even those under a half inch in length--are plenty lethal enough to kill a deer or even larger animal. These are true arrowheads, in that they were attached to arrows and shot using a bow. An arrow tipped with stone would easily pass right through a bird, which are more easily obtained using a net.
Myth Number 3: The hafted tools with the round ends are meant for stunning prey rather than killing it.
So-called 'blunt points' or 'stunners' are actually regular dart points that have been reworked so that the pointy end is a long horizontal plane. At least one edge of the plane would have been purposefully sharpened. These are excellent scraping tools, for working animal hides or wood, with a ready-made hafting element. The proper term for these kinds of tools is hafted scrapers.
Myth Number 4: The reason you see so many projectile points around is there was a lot of warfare between tribes in prehistory.
Investigation of blood residues on stone projectile points reveal that the DNA on the majority of stone tools are from animals, not humans; and thus, most often used as hunting tools. Although there was warfare in prehistory, it was far less frequent than hunting for food.
Myth Number 5: Arrowheads are made by heating a rock and then dripping water on it.
A stone projectile point is made by a sustained effort of chipping and flaking stone called flint knapping. Flintknappers work a raw piece of stone into its shape by hitting it with another stone (called percussion flaking) and/or using a stone or deer antler and soft pressure (pressure flaking) to get the final product to just the right shape and size.
More Projectile Point Myths
Faithful reader Chris R. Loendorf (Archaeologist at Gila River Indian Community) suggested these additional myths ought to be mentioned.
Myth Number 6: It takes a really long time to make an arrowpoint.
While it is true that making some stone tools (e.g., Clovis points) requires time and considerable skill, flintkapping in general is not a time intensive task nor does it necessarily require skill. Expedient flake tools can be made in a matter of seconds by anyone who is capable of swinging a rock. Even producing more complicated tools is not necessarily a time intensive task (though they do require more skill). Arrowheads, for example, can be made from start to finish in less than 15 minutes; John Bourke (1890) timed an Apache making four stone points and the average was only 6 1/2 minutes.
Myth Number 7: All arrows (darts or spears) had stone projectile points attached, to 'balance' the shaft.
Instead, the ends of the arrows were simply sharpened or points made from other materials (e.g., shell, teeth, or antler) were attached. A heavy point actually destabilizes an arrow during launch, and the shaft will fly out from the bow when fitted with a heavy head. When an arrow is launched from a bow, the nock (i.e., notch for the bowstring) is accelerated before the tip. The greater velocity of the nock when combined with the inertia of a tip of higher density than the shaft and on its opposite end, tends to spin the distal end of the arrow forward. A heavy point also increases stresses that occur in the shaft when rapidly accelerated from the opposite end, which can result in "porpoising" of the projectile or even shatter it if severe.Myth Number 8: Stone projectile points are far more effective a weapon than a sharpened spear.
Recent experiments conducted by the Discovery Channel's Myth Busters team under the direction of archaeologists Nichole Waguespack and Todd Surovell (Waguespack et al. 2009) revealed that stone tools only penetrate about 10% deeper into animal carcasses than sharpened sticks. A recent study by Sisk and Shea (2009) found that point penetration might be related to the width of a projectile point.
Next: Some Little Known Facts
See the Bibliography of Projectile Point Experiments for references