Trampling in coastal sites: An experimental study on the effects of shell on bone in coastal sediment

Faunal remains are often recovered from shelly deposits in coastal sites but little is known about the trampling effects of shell on bone. Here, trampling experiments were conducted to investigate these effects and to describe the types of surface modification that could occur on bone in coastal sediment. The results suggest that bone is significantly more likely to exhibit surface modification if trampled in shelly rather than sandy sediment. Burnt bone is less likely to display trampling modification. This is probably because, prior to trampling, burning exfoliates the cortex making the observation of markings on bone problematic. Pitting, trampling lines and sheen were found to be the most prevalent form of surface modification. Pitting is a particularly over-looked criterion and its presence on archaeological bone suggests that the effects of trampling should be considered in zooarchaeological analyses. The pervasiveness of sheen and trampling lines on the experimental bone makes it possible that some incidence of trampling could be mistaken for use-wear or intentional polish. However, the vast majority of trampled bone exhibits sheen which does not resemble anthropogenic specimens and trampling is unlikely to smooth bone fragment edges. This experiment demonstrates that modification caused by trampling can generally be differentiated from butchery markings. The high percentage of modified trampled bone in the shelly deposits suggests that some shell-marks may be mistaken for cut marks, if recovered in an archaeological context.