How Neanderthals gripped retouchers: experimental reconstruction of the manipulation of bone retouchers by Neanderthal stone knappers

When studying bone retouchers, researchers pay close attention to the morphological characteristics of the tool’s active zone, and the lithic raw material processed. In our research, we found that the orientation of the bone retoucher in the hand and the grip employed to retain and manipulate it are crucial factors that affect the morphological characteristics of the retoucher’s active zone. By examining two alternative grips for manipulating bone retouchers ((1) Using all the fingers of one hand in a power grip; (2) Using only the first three digits of one hand in a pinch grip), we found that when the retoucher is held in the first manner, the active area is larger, as is the amount of bone removed by the retoucher. When the retoucher was pinched with only three fingers in a precision grip, retouch damage was more densely concentrated and less bone was removed. The orientation of the retoucher in the hand and the grip employed have a greater influence on the active area than the extent of retoucher use, which we assessed by measuring the number of stone tool edges processed. By gripping the retoucher with all the fingers of one hand, the knapper automatically applies greater force, which results in the removal of more bone. Comparison of experimental bone retouchers with those recovered from Middle Paleolithic archaeological contexts in Chagyrskaya Cave (Altai, Russia) revealed that Altai Neanderthals practiced two methods of grasping bone retouchers, with a three-finger pinch grip being dominant.