Malacology
Malacology is the science dealing with the study of the Mollusca. Molluscs are a group of invertebrate animals and with probably more than 100.000 living species they are the second in size to the Arthropoda (insects, crustaceans etc.). The phylum Mollusca is divided into several classes such as the gastropods (snails and slugs), bivalves (cockles, mussels, oysters etc.), cephalopods (cuttlefish, squids, octopusus etc.), scaphopods (tusk shells), polyplacophora (chitons), monoplacophora and aplcaophora (worm molluscs). Most species of molluscs carry a calcareous shell covering the soft-bodied animal but some groups do not have a shell (terrestrial and marine slugs, most cephalopods, aplacophora).
The molluscs are inhabiting marine, land and freshwater habitats and occupy a significant place in nearly every ecosystem. Molluscs play an important role as food and their shells are used in many ways for jewellery and arts and crafts. Many species serve as ecological indicators for the condition of habitats. Fossil shells are used for age determination of rocks and can serve for reconstruction of past ecosystems. Some species are vectors of parasites which cause severe human diseases.
However, because of pollution and destruction of their often restricted living spaces many species especially of terrestrial gastropods and freshwater bivalves are in danger of extinction and need conservation measures. Their varied and colorful shells are searched after by many shell collectors all over the world. Some attractive seashells like the giant Tridacna clams may not be traded under the law of the Convention on International Trade of Endangered Species.
Because of the important role which molluscs play in nearly every ecosystem, because of their economical value and because of their good abilities to get preserved as fossils molluscs and their shells are an interesting and fascinating field of research with many applied aspects.
