-
Chloe Geddes posted an image in the group What is it? from the myFOSSIL app 3 years, 6 months ago
3 years, 6 months ago3 years, 6 months agoA rather impressive collection has been given to me due to some unfortunate events and so I do not have a way of questioning the collector. Any ideas? #fossil
Early Triassic ammonite?
Ammonites are generally coiled, this guy is only sort of coiled. Is that characteristic of the Triassic?
Many heteromorph ammonites have interesting shell shapes.
shells coiled like this are more typical of heteromorph ammonites, who lived in the cretaceous. this is a beautiful specimen, and definitely rare
Well guys, remember that ammonites are just orthacones that curled up their shells. That transformation took place from the devonian to the Triassic. In between straight and tightly coiled shells you find in between ones such as this. Triassic was a guess because it’s so high quality I wouldn’t think it would be as old, also the shell is ridged and that is a trait usually seen in Mesozoic era ammonites. @daniel-park @leonardo-miranda
emericiceras or crioceratites are my suggestions
or as @a-trilobite said, one of the transitional devonian stages. maybe anetoceras
Wow! Thank you guys so much!! I really appreciate it!!
👍
Y’all are the best 🙂
on the iow there is a species of ammonite that is only partly coiled from the early cretaceous.
called tropeum I think.
Is it just me or does it seem like it would be WAY harder to swim with a partially curled shell. So much more friction as you move! I am amazed with all I am learning about transitional ammonites!
just helping out fellow paleontologists ;D
partially curled shells would indeed be inadequate for locomotion. but there’s stranger shells out there. Diplomoceras looked like a paperclip. Nipponites looked like a scribble
That’s why scientists are baffled by these evolutionary oddities
I guess you’ve got to get from point A to point B some how! I will definitely be looking those guys up now! Thanks @leonardo-Miranda
see that you do. you’ll be baffled out of your mind by these picasso creatures
@leonardo-miranda I’ve asked this question on the biology Stack Exchange, and they responded with two reasons. One, some of the partially curled ammonites could “hook” to aquatic plants so they wouldn’t drift away while brooding, and two, partially curled shells such as this one could travel with the currents (due to more drag) faster than normal ammonites if they turned sideways and if they turned edgewise, they would travel at about the same speed.
Also, ammonites like Nipponites could use their weird twisted shells to also make more drag, and just float with the currents quickly, like a jellyfish. Interesting stuff!
@daniel-park truly fascinating. happy to see some answers. l was thinking, the shells of tube worms who grow on rocks and intertwined with coral, resemble those of some heteromorphs like Nipponites. maybe they also lived sedentary lifestyles with shells adhered or tied around coral branches, sticking out their rim of tentacles to filter feed?
@leonardo-miranda Possibly, that sound plausible! These paleontologists seem to agree with you- https://www.sciencemag.org/news/2012/04/hanging-out-ancient-oasis
Supposedly, they could have hung out near methane-rich places at the sea floor for food.
great to see a paper that agrees with me!
I always see two types of reconstructions at museums-ones where the ammonites and orthacones are sprawled out on the sea floor, and ones where they’re swimming in the water. I’d think that the swimming ones are more accurate, but does anyone know for sure?
Also if you want to be a paleontologist do you have to memorize all the dates, times, events, and taxonomic groups and all the species and the evolutionary history of them?
@a-trilobite not at all. remember palaeontology is quite complicated with different subdivisions. different palaeontologists may specialise in different fields. some reconstruct animals via art, some go out and dig, some prepare fossils in labs, some work in micropalaeontology…. and you also choose what creatures you specialise in. a palaeobotanist would know nothing about brachiopods, as he’d work with plants. a prosauropod researcher would know nothing about orthocones. a researcher of continental shift in the silurian would know nothing about synapsid footprints. and so on. just learn the field you specialise in.
since l have 4 years before l go to university, l don’t know the finer details, but l know that l will have to major in biology and geology, and also take geography as it will help
Ecology and genetics could help too.