ammonites are extinct
If not specified as trace fossil of Ammonites, it should be a body fossil. Ammonites is the name of the creature.
Ammonites are named for the Egyptian god Ammon, who had a ram's head. The shells of ammonites are spirals like the horns of a ram.
Various aquatic reptiles were predators of ammonites. Fossils of damaged ammonites have been found with teeth marks from Plesiosaurs.
Ammonites may grow over 2 metres. The giant clammay grow up towards 1.5 metres. Both of these are roughly circular in shape. Nautiloids of a linear shape (actually a long thin cone) were up to 3.5 metres in length.But I expect that if these were coiled as the Ammonites were, they would not have a greater overall diameter.
Squid
plankton
No, the Japanese are a modern ethnic group of people from Japan. Ammonites are ancient marine animals that went extinct millions of years ago.
Fish grow with age. Some only grow to the size of the tank while others grow to a maximum size no mater the size of their environment.
Ammonites went extinct at the end of the Cretaceous Period.
Ammonites are very common fossils from the Jurassic Period. They were dominant in the ocean during and before the Jurassic Period.
Ammonites went extinct at the same time as the dinosaurs, about sixty-five million years ago.