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Nautilus shells were popular items in the Renaissance and Baroque cabinet of curiosities and were often mounted by goldsmiths on a thin stem to make extravagant nautilus shell cups. The low fecundity , late maturity, long gestation period and long life-span of nautiluses suggest that these species are vulnerable to overexploitation and demand ...
The chambered nautilus (Nautilus pompilius), also called the pearly nautilus, is the best-known species of nautilus. The shell, when cut away, reveals a lining of lustrous nacre and displays a nearly perfect equiangular spiral, although it is not a golden spiral. The shell exhibits countershading, being light on the bottom and dark on top. This ...
Empty nautilus shells may drift a considerable distance and have been reported from Japan, India and Africa. Undoubtedly the same applies to the shells of fossil nautiloids, the gas inside the shell keeping it buoyant for some time after the animal's death, allowing the empty shell to be carried some distance from where the animal lived before ...
Many biological structures including the shells of mollusks. [14] In these cases, the reason may be construction from expanding similar shapes, as is the case for polygonal figures. Logarithmic spiral beaches can form as the result of wave refraction and diffraction by the coast. Half Moon Bay (California) is an example of such a type of beach ...
Marine mollusk shells that are familiar to beachcombers and thus most likely to be called "seashells" are the shells of marine species of bivalves (or clams), gastropods (or snails), scaphopods (or tusk shells), polyplacophorans (or chitons), and cephalopods (such as nautilus and spirula). These shells are very often the most commonly ...
During this time, their shells were more varied than those found in species of living Nautilus, ranging from curved (cyrtoconic), through loosely coiled (gyroconic), to tightly coiled forms, represented by the Rutoceratidae, Tetragonoceratidae, and Centroceratidae.
Lil History Lesson for the day, on August 3rd, 1958 the Nautilus submarine was the first submarine in history to travel under the north pole — Josh Paydon (@Dahl0negaG0ld) August 3, 2015
Nautilus is the type genus of the family Nautilidae, originally defined as any coiled-shell species with simple sutures, or walls, between shell compartments. [7] Any shells with complex sutures were assigned to the genus Ammonites .