Specialization on specific foods is the major factor driving diversification of marine gastropods. Many, like Triphora feed on a specific food (in this case sponges) and their range is limited to their food's occurrence. In the oceans, where greatest gastropod abundance is in or near the intertidal zones, temperature and salinity also limit a species' range. Freshwater species are limited in range to streams and lakes. The veliger larval stage has been eliminated in freshwater species, otherwise free dispersal would result in downstream colonization only. Freshwater prosobranchs incubate their young inside the female, while freshwater (and terrestrial) pulmonates attatch thei eggs to anything available.

Figure 21. This finger limpet is highly specialized to it's environment; it can only live in the harsh intertidal conditions it has adapted to. It eats algea it scrapes off rocks with a radula, the tooth organ found in gastropods.

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Evolution

Morphology

Fossil Record

Ecology

Glossary