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Could ammonites close their shells?
In one of the Walking With… documentaries (I think it was Dinosaurs), some ammonites are seen retreating inside their shells and then closing it with a sort of lid. Did this lid actually exist? Do nautiloids have a similar structure? Where would the lid be when open, if it did/does exist?
3 Answers
- Tundra RobLv 77 years agoFavorite Answer
Come species of ammonites had a plate called an "Aptychus" which some scientists believed the ammonites used to cover the opening in their shell. However other scientists believe this structure was used more like a jaw, or as a support structure for the ammonites mandibles.
Source(s): https://en.wikipedia.org/wiki/Aptychus - busterwasmycatLv 77 years ago
I do not believe that ammonites have/had a cover. gastropods did and do. completely different creatures. the term for the cover is operculum.
- Anonymous7 years ago
No the exit of its shell was open. It could hide inside its shell but it couldn't close it.
