Evidence of butchery and hominid activities at Torralba and Ambrona; an evaluation using microscopic techniques

Torralba and Ambrona have been interpreted as butchery sites for many years, a contention recently challenged; natural death or carnivore activities are invoked as an alternative explanation. Scanning electron microscopy (SEM) of bone surface replicas distinguishes among hominid-produced cutmarks, carnivore tooth scratches, and other types of bone damage. A sample of 102 replicas, comprising the most likely cutmarks on a combined sample of roughly 3000 fossils from Torralba and Ambrona, were scanned to determine the major agent of damage. Microscopically verified cutmarks are present, but rare, occurring in less than 1% of the bones in the combined sample. Carnivore tooth scratches are comparably rare. In contrast, evidence of sedimentary abrasion, which obliterates the diagnostic features of cutmarks, is present on nearly every bone from Torralba and Ambrona. It remains unresolved whether cutmarks were initially more common on these bones and were subsequently obliterated by abrasion, or whether the incidence of cutmarks was always low. These data demonstrate clearly that hominids and carnivores each damaged some bones at Torralba and Ambrona, but the frequency of each type of mark is too low to confirm strongly the interpretation of these sites as either butchery or carnivore remains.