Ammonite Fossil

Ammonoidea

Ammonoids are extinct, typically coiled-shelled cephalopods composing the subclass Ammonoidea. They are more closely related to living octopuses, squid, and cuttlefish than they are to nautiluses, which their shells resemble. The earliest ammonoids appeared during the Emsian stage of the Early Devonian, around 410-408 million years ago, with the last species vanishing during or soon after the Cretaceous–Paleogene extinction event approximately 66 million years ago. They are often called ammonites, which is most frequently used for members of the order Ammonitida, the only remaining group of ammonoids from the Jurassic up until their extinction.

Fossil

A fossil is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved in amber, hair, petrified wood and DNA remnants. The totality of fossils is known as the fossil record. Though the fossil record is incomplete, numerous studies have demonstrated that there is enough information available to give a good understanding of the pattern of diversification of life on Earth, and it can fill gaps in our understanding of the sequence of evolution on earth.

ammonite

Noun

1. Any of an extinct group of cephalopods of the subclass Ammonoidea; a fossil shell of such an animal.

Noun

1. An explosive prepared from a mixture of TNT and ammonium nitrate; a form of amatol, popular in Eastern Europe and China.

fossil

Noun

1. The mineralized remains of an animal or plant.
2. Any preserved evidence of ancient life, including shells, imprints, burrows, coprolites, and organically-produced chemicals.