cords and knots which would also have been adequate for the production of bows is implied. The employment of snares also demonstrates a practical understanding of the latent energy stored in bent branches, the main principle of bow construction. Cords and knots are implied by use-wear facets on perforated shell beads around 72,000 years old from Blombos. Archeologists in Louisiana have discovered that early Native Americans used Alligator gar scales as arrow heads. "Hunting with a bow and arrow requires intricate multi-staged planning, material collection and tool preparation and implies a range of innovative social and communication skills." Design Arrowheads are attached to arrow shafts to be shot from a bow; similar types of projectile points may be attached to a spear and "thrown" by means of an atlatl (spear thrower). The arrowhead or projectile point is the primary functional part of the arrow, and plays the largest role in determining its purpose. Some arrows may simply use a sharpened tip of the solid shaft, but it is far more common for separate arrowheads to be made, usually from metal, horn, rock, or some other hard material. Arrowheads may be attached to the shaft with a cap, a socket tang, or inserted into a split in the shaft and held by a process called hafting. Points attached with caps are simply slid snugly over the end of the shaft, or may be held on with hot glue. In medieval Europe, arrowheads were adhered with hide glue. Split-shaft construction involves splitting the arrow shaft lengthwise, inserting the arrowhead, and securing it using ferrule, sinew, rope, or wire. Modern arrowheads used for hunting come in a variety of classes and styles. Many traditionalist archers choose heads made of modern high carbon steel that closely resemble traditional stone heads (see Variants). Other classes of broadheads referred to as "mechanical" and "hybrid" are gaining popularity. Often, these heads rely on force created by passing through an animal to expand or open. Variants Arrowheads are usually separated by function: Bodkin points are short, rigid points with a small cross-section. They were made of unhardened iron and may have been used for better or longer flight, or for cheaper production. It has been suggested that the bodkin came into its own as a means of penetrating armour, however limited research has so far found no hardened bodkin points, so it appears likely that it was first