Many, many thanks to Andy for writing this interesting article. It is really appreciated as these articles do take quite some time to write and compile and quite a lot of work is involved. If anyone would like to write a similar report about their local fossil beds (as long as they contain ammonites or other cephalopod fossils) please be our guest! Contributions are most welcome.
It is fascinating to see the variation in cephalopod fossils and the differences in location and age at the different sites Kevin, Andy, Spartacus, and many other contributors have shown us over the last couple of years. Ammonites in particular display so many subtle variations on a theme, and looking at Andy’s two stunning examples at the end of the article it’s interesting to note how similar they look to some of the much later Folkestone examples. This is despite Andy’s dating to over 80 million years earlier, and belonging to different families. “If it ain’t broke, don’t fix it” seems to be the pattern in basic coiled true ammonite design with similar recurring forms throughout their history.
The last two images were a nice surprise, thanks Andy! I’m not sure of the species exactly but they are cracking examples of basic ammonitic shell forms, i.e the loosely coiled evolute and tightly coiled involute forms. The top example is an evolute ammonite, whereby the early whorls are barely overlapped by later growth, whilst the later example is a near-involute ammonite where the shell whorls almost completely overlap the earlier growth rendering them nearly invisible, much akin the modern Nautilus which is completely involute.
Thanks again, Andy. Please let us know more details about your prepped ammonites!
great article and pics Andy :notworthy: Ravenscar has now been added to my long (extremely!) list of places to visit!
