Ammonites are very common fossils from the Jurassic Period. They were dominant in the ocean during and before the Jurassic Period.
Crinoids and ammonites were the dominant marine life forms during the Mississippian stage of the Carboniferous period.
ammonites are extinct
The dominant organisms in the Mesozoic Era were dinosaurs, which ruled the land, along with marine reptiles and ammonites in the oceans. In the later part of the era, mammals and birds began to diversify and emerge as important groups of organisms.
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.
Squid
Ammonites first appeared during the Devonian Period within the Paleozoic Era.
Ammonites went extinct at the end of the Cretaceous Period.
Ammonites went extinct at the same time as the dinosaurs, about sixty-five million years ago.
Ammonites are the most widely-known and abundant fossils in the world. The name "ammonites" came from the Greek god Ammon. Ammonites include squid, octopus, snails, cuttlefish, and nautilus.
ammonites
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