Glossary

Aperture The opening of a gastropod shell from which the mollusk comes out while alive.

Bivalvia A molluskan class of marine and freshwater animals that have a shell composed of two valves.

Gastropoda Class of mollusks that are snails, mostly having a shell that is usually coiled, that live in marine, freshwater, and terrestrial environments. A few members of this class have no external shell.

Operculum Chitinous or calcareous plate attached to a snail’s foot with which it closes the shell aperture when the animal withdraws into its shell.

Polyplacophora A mollusk class that has a shell made of eight plates. Chitons.

Scaphopoda A molluskan class of animals that burrow into sandy bottoms, usually at great depths, and have a slightly curved tube-like shell that is open at both ends. Tusk shells.

Sclerochronology The rate of growth of an animal as studied by the formation of rings (daily, seasonal, or annual).

Spire The top part of a gastropod shell that includes all whorls except the last one.

Umbo The tip of a bivalve behind the hinge area where the two valves connect to each other (plural: umbones).

Invertebrates are animals that do not have a vertebral column. Most, notably mollusks (mollusc = British spelling; mollusk = American spelling), arthropods, echinoderms, corals, and very rarely sponges can be found in the archaeological record, whether the result of human activities or reflecting the former natural environment of a site. The invertebrate remains most commonly encountered in archaeological sites are those of phylum Mollusca, the second largest in the animal kingdom (after Arthropoda) and consists of about 100 000 species. The phylum is divided into eight classes, five of which bear shells that may be encountered in the archaeological record: Gastropoda (snails), Bivalvia (also known as Pelecypoda or Lamellibranchia; bivalves), Scaphopoda (tusk shells), Polyplacophora (chitons), and Cephalopoda (cuttlefish) (Figure 1). The latter have a small internal skeleton that is rarely encountered in archaeological sites. All others have an external skeleton, the shell, made of calcium carbonate.

Most molluskan remains retrieved from archaeological sites occur naturally in marine environments while certain snails and bivalves are present also in freshwaters (rivers, springs, and lakes), and some snails are exclusively terrestrial.