Human behavior or taphonomy? On the breakage of Eastern North American Paleoindian endscrapers

Endscrapers, the most abundant tool class at Eastern North American Paleoindian sites, are flaked stone specimens predominately used for scraping hides. They are found broken in high frequencies at these sites, a pattern that has been attributed to use. However, previous experimental and ethnographic research on endscrapers suggests that they are difficult to break. We present a series of replication experiments assessing the amount of force required for endscraper breakage, as well as the amount of force generated during human use. We also analyze which morphometric variable best predicts the breakage force. Our results demonstrate that the force humans can generate is far below the breakage force, which is best predicted by endscraper thickness. Finally, we examine an actual Paleoindian endscraper assemblage, concluding that human use was not the cause for breakage. Taphonomic factors such as plowing, or trampling, are a much better potential explanation for the high breakage frequencies present at Paleoindian sites.