Rummages through the core collection of British cephalopods (Part 1)

Neale Monks (UK) Alongside trilobites, ammonites are by far the most popular invertebrate fossils. Whether you’re an enthusiastic fieldworker or more of an armchair geologist, chances are that your collection includes a fair number of ammonites of one sort or another. These may well have names and localities, but details on the ecology of ammonites is often lacking, and relatively few popular books on geology say much about how ammonites lived beyond the fact they were marine invertebrates related to modern squids and octopuses. As it happens, British geologists are well served when it comes to ammonites, with extensive exposures of Jurassic and Cretaceous strata accessible across the country, from the Kent coast to the Isle of Skye. Coastal exposures are the ideal, of course, but old quarries and other inland sites can be fruitful too, and the UKGE website is there to help anyone wanting to build up their own ammonite collection (see https://www.ukge.com/). Belemnites are often found alongside ammonites, and being cephalopods as well, resembled ammonites in many ways. The biggest difference was that they were more squid-shaped animals, with the buoyant shell inside the animal instead of outside. They were probably quite good swimmers, but whether they foraged close to the seafloor like cuttlefish, or high up the water column like squid, remains unclear. It may well be that different belemnites did different things, and the variation we see in belemnite fossils reflects this. But what, if anything, is the quintessential British ammonite? And if such a … Read More