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Gastropod Main
Glossary
References
Links
Hooper Main |
Fossil Record 4
The fossil record shows that recurring themes often occur in gastropod evolution. The snails continued to diversify from the Cambrian onwards. By the Carboniferous, a time of great gastropod diversity, the caenogastropods had begun to colonise the land. Amongst the very oldest land snails, the Dendropupae found in Joggins, Nova Scotia, are from this time (about 310 Ma). Though the caenogastropods died out soon after, the migration onto land would be repeated by pulmonates in the Cretaceous. Modern prosobranchs are also known from the end of the cretaceous (65 Ma), with the first records of modern pulmonates at 54 Ma. Since then, gastropod advances continued at a slow pace to this day.
| Figure 17. A Dendropupa vetusta (bottom) snail form Nova Scotia, first described by Dawson, is one of the oldest known terrestrial gastropods. A similarly old terrestrial Zonites priscus is from the same locality (top). Colonisation of different habitats and then extinction, and repitition of form and functions recur often in gastropod evolution. The Caenogastropods were possibly the first terrestrial members to survive in numbers, unfortunately they dissapeared near the end of the Carboniferous. |  |
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