Nota: A tradução desta entrada está atualmente em revisão de qualidade, portanto parte do conteúdo é exibida temporariamente apenas em inglês.
Este verbete ainda não foi traduzido para o seu idioma, portanto o original é exibido abaixo.
ammonite
This term refers specifically to the extinct cephalopods of the subclass Ammonoidea. In a scientific or paleontological context, it is used to describe the biological organism, but in common usage, it almost always refers to the fossilized remains of the spiral shell.
Because these fossils are frequently used as index fossils for dating geological strata, the word often appears in discussions regarding the Mesozoic era. It is distinct from the modern nautilus, despite the similar shell shape, due to the internal structure of the septa and sutures.
Meanings
Examples
The museum has a stunning collection of ammonite fossils from the Jurassic period.
Look at this spiral pattern on the ammonite shell.
I wonder if the ammonite was a predator or a scavenger in its own time.
The geologist identified the rock layer by the presence of an ammonite.
Wait, is this an ammonite or a nautilus fossil?
An ammonite is an extinct cephalopod that lived millions of years ago.
An ammonite is an extinct cephalopod that lived millions of years ago.
The polished surface of the ammonite reveals the intricate internal chambers.
We found a perfectly preserved ammonite during our field trip to the coast.