THE ROLE OF VERBAL INTERACTION DURING EXPERIMENTAL BIFACIAL STONE TOOL MANUFACTURE

Abstract

Many researchers have hypothesized an analogous, and possibly evolutionary, relationship between Paleolithic stone tool manufacture and language. This study uses a unique design to investigate how spoken language may affect the transmission of learning to make stone tools and comes to surprising results that may have important implications for our views of this relationship. We conducted an experiment to test the effect of verbal communication on large core biface manufacture during the earliest stages of learning. Previously untrained flintknappers were assigned to two different communication conditions, one with and one without spoken language, and were instructed to replicate the bifaces produced by the same instructor. The attempted bifaces (total = 334) from the two groups were compared using an Elliptical Fourier analysis, the Flip Test, and a rating scale by an independent lithicist. We found no significant difference in the overall shape, symmetry, or other measures of skill among the two groups, using all three of these methods. Analysis of the 18,149 debitage elements from the experiment, however, revealed that the two groups set up their striking platforms in fundamentally different ways. The nonverbal group produced more efficient flakes than the verbal group, as evidenced by the significantly higher ratios of platform width to platform thickness and size to mass of the nonverbal subjects’ flakes. These results indicate that verbal interaction is not a necessary component of the transmission of the overall shape, form, and symmetry of a biface in modern human novice subjects, and it can hinder the progress of verbal learners because of their tendency to over-imitate actions of the instructor that exceed their current skill set.