Researchers have found a remarkable effect while studying how marine particles sink, which could affect the way scientists assess global carbon fluxes.
Ammonites are an group of marine animals of the subclass Ammonoidea in the class Cephalopoda. They are excellent index fossils, and it is often possible to link the rock layer in which they are found to specific geologic time periods.mmonites are an group of marine animals of the subclass Ammonoidea in the class Cephalopoda. They are excellent index fossils, and it is often possible to link the rock layer in which they are found to specific geologic time periods.
Ammonites (subclass Ammonoidea) can be distinguished by their septa, the dividing walls that separate the chambers in the phragmocone, by the nature of their sutures where the septa joint the outer shell wall, and in general by their siphuncles.mmonites vary greatly in the ornamentation (surface relief) of their shells. Some may be smooth and relatively featureless, except for growth lines, and resemble that of the modern Nautilus. In others, various patterns of spiral ridges and ribs or even spines are shown.