The Consumption of Seafood by the Populations of Islamic Silves (South Portugal)

Abstract

Malacology is the scientific branch of Invertebrate Zoology dealing with the study of the Phylum Mollusca. It includes soft-bodied invertebrates and topics such as taxonomy, systematics, taphonomy, biostratigraphy, evolution, ecology, biogeography, biotic resources, and human interactions. Applied to Palaeontology and Archaeology, Malacology enables palaeoecological, palaeoclimatic, and cultural studies and statistical analyses.

The case study focused on the medieval Silves town (Xelbmedina; Algarve, southern Portugal), its Islamic population, and the interactions between humans and edible mollusc rich environments. It includes aspects such as: food consumption, economy, estuarine biotope exploitation, and cultural shell usage.

The studied assemblages were collected from a palatial context of the Alcazaba that is estimated to be occupied from the 6^th/7^th century to the 16^thcentury. The sample studied belongs to different historical periods and consumed by different social levels. The archaeological campaigns were directed by Prof. Rosa Varela Gomes from the Universidade NOVA de Lisboa and archived in the Laboratory of Archaeology of the Faculdade de Ciências Sociais e Humanas (FCSH).

The work focuses on 12,605 skeletal parts, mostly fragmented shells; subjected to systematic, taxonomic, and taphonomic identifications after laboratorial preparations. These were followed by a bulk sample quantitative analysis to obtain statistical data regarding species representativeness, palaeoecological interpretations of surrounding aquatic biotopes, and anthropic interactions, with a shellfish and edible mollusc consumption emphasis. Analysis has revealed 25 bivalve, 16 gastropod, 1 crustacean, and 1 barnacle species from marine and estuarine environments, and 3 terrestrial gastropod species. Ruditapes decussatus (venus clam) is predominant in almost all sampled layers, followed by Ostrea edulis (oyster) and Cerastoderma edule (cockle). Wide mollusc variety was also observed, averaging 12 species per excavated square. Species abundances indicate the exploration of estuarine environments similar to the nearby Arade river. Several valves, intentionally perforated or showing umbonal abrasion facets, were interpreted as fishing net ballasts. A large convex Pecten maximus(scallop) valve may result from domestic tool usage.

This work is a first approach to a larger zooarchaeological collection. Further studies will provide crucial data on this important medieval Islamic centre of the Iberian Peninsula.