Compression and digestion as agents of vertebral deformation in Sciaenidae, Merlucidae and Gadidae remains: an experimental study to interpret archaeological assemblages

Fish taphonomy from archaeological sites provides considerable useful information about human behaviours and environmental contexts as potential food remains or as natural occurrences. This article focuses on mechanical deformations of fish vertebrae and the potential information about predation, diachrony in the deposition of the remains, and time-averaging and reworking processes these provide. Experimental work using uniaxial compression on dry and water-soaked vertebrae from modern skeletons [Meagre (Argyrosomus regius, Asso 1801), European hake (Merluccius merluccius, L. 1758) and Pouting (Trisopterus luscus, L. 1758)] compared to modern digested fish vertebrae from a predator of extreme taphonomic modification (European otter, Lutra lutra) allowed us to assess key features to identify different processes and site formation agents. Our results are also compared with experimental assemblages modified by water and dry abiotic abrasion. These provide a baseline to understand the nature of the agents causing modifications to archaeological vertebrae from the Middle Holocene Argentinian sites of El Americano II and Barrio Las Dunas and the Magdalenian site of Santa Catalina (Basque Country, Spain). The experimental frame of reference allowed us to identify dry compression on Barrio Las Dunas and Santa Catalina assemblages and wet compression on El Americano II and Santa Catalina sites, improving our interpretation of the formation of those archaeological deposits and their fish assemblages. These data allow one to explore with a higher degree of confidence than has been hitherto possible how humans obtained, processed, and discarded fish in former times.