1 10 1 https://wserv3.esc.cam.ac.uk/p1acollections/files/original/e36a8c8a1389dbf0209647d40c976b80.png 58b03cc689e998b264bed6110477c2f8 Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource Fossils Description An account of the resource <p>Welcome to the fossils section of the website. This is designed to help you learn the different characteristics of each major fossil group so that you are able to distinguish between them.</p> <p>First year students, please refer to the specimens housed in the first year teaching laboratory. There is no substitute for handling the specimens themselves; this website is just an accessory to help you along the way.</p> <p>Animals occupy different environments, have different life habits and lived through different periods in geological time. It is good to be aware of these differences in lifestyle and timing, within and between phyla, classes, orders and families.</p> Physical Object An inanimate, three-dimensional object or substance. Note that digital representations of, or surrogates for, these objects should use Moving Image, Still Image, Text or one of the other types. Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource <h2>Nautiloid</h2> Description An account of the resource <h2>Taxonomy</h2> <p>Phylum: Mollusca</p> <p>Class: Cephalopoda</p> <h2>Diagnostic features</h2> <p>Simple suture</p> <p>Chambers</p> <p>Central siphuncle</p> <p>Straight, curved or coiled shell</p> <h2>Stratigraphic range</h2> <p>Cambrian to recent</p> <p>Straight forms: Cambrian to Permian</p> <p>Coiled forms: Devonian to Present</p> <h2>Way of life</h2> <span>Nektonic (jet propulsion)</span><br /><p>Predatory</p> <p>Buoyancy controlled by changing gas/liquid contents of chambers</p> <p>Marine</p> <h2>Preservation</h2> <p>Commonly preserved as internal moulds</p> <p>Modern<span> </span><em></em>nautiloids preserved with original shell material</p> <p><a href="https://www.digitalatlasofancientlife.org/learn/nature-fossil-record/types-of-fossil-preservation/">Learn about types of preservation</a></p> <h2>Advanced notes</h2> <p>Nautiloids originated in the Cambrian period, and radiated during the Ordovician. These early nautiloids had conical shaped shells. In the Silurian some nautiloids used curved shells, and by the Devonian some were coiled. The evolution of the coiled shell from the straight is thought to be driven, at least in part, by increased mobility of a coiled shell compared to a long straight one.</p> <p>Nautiloids could be confused with ammonoids. You can distinguish them by the location of the siphuncle and the complexity of the suture pattern. Nautiloids, unlike ammonoids, are not extinct, although only six species remain today (compared to thousands in the Palaeozoic). This means that if presented with modern shell material it is likely a nautiloid and not an ammonoid.</p> <h2>Specimens</h2> <p><a href="/p1acollections/exhibits/show/nautiloids">Browse nautiloids</a></p> <h2>External links</h2> <p><a href="https://www.youtube.com/watch?v=2ilSDcZAXNM" target="_blank" rel="noreferrer noopener">Telling planispiral fossils apart</a></p> nektonic