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, whi
Pleuroceras solare, Little Switzerland, Bavaria, Germany
A variety of ammonite forms, from Ernst Haeckel's 1904 Kunstformen der Natur (Art Forms of Nature)
Fossil of Parapuzosia seppenradensis, one of the largest known ammonites
Oppelia in association with its aptychi plates
A cephalopod is any member of the molluscan class Cephalopoda such as a squid, octopus, cuttlefish, or nautilus. These exclusively marine animals are characterized by bilateral body symmetry, a promin
Ammonoidea
…Ammonoids are extinct, typically coiled-shelled cephalopods composing the subclass Ammonoidea. They are more closely related to living octopuses, squid, and cuttlefish (which compose the clade Coleoidea) than…
The primitive nautilus eye functions similarly to a pinhole camera.
A cuttlefish with W-shaped pupils which may help them discern colors
This broadclub cuttlefish (Sepia latimanus) can change from camouflage tans and browns (top) to yellow with dark highlights (bottom) in less than a second.