enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Cephalopod - Wikipedia

    en.wikipedia.org/wiki/Cephalopod

    The morphological construction gives cephalopod eyes the same performance as shark eyes; however, their construction differs, as cephalopods lack a cornea and have an everted retina. [23] Cephalopods' eyes are also sensitive to the plane of polarization of light. [24] Unlike many other cephalopods, nautiluses do not have good vision; their eye ...

  3. Coleoidea - Wikipedia

    en.wikipedia.org/wiki/Coleoidea

    Some older fossils have been described from the Devonian, [4] but paleontologists disagree about whether they are coleoids. [5] Other cephalopods with internal shells, which could represent coleoids but may also denote the independent internalization of the shell, are known from the Silurian. [6]

  4. Nautilus - Wikipedia

    en.wikipedia.org/wiki/Nautilus

    The shell is coiled, aragonitic, [22] nacreous and pressure-resistant, imploding at a depth of about 800 m (2,600 ft). The nautilus shell is composed of two layers: a matte white outer layer with dark orange stripes, [23] and a striking white iridescent inner layer. The innermost portion of the shell is a pearlescent blue-gray.

  5. Evolution of cephalopods - Wikipedia

    en.wikipedia.org/wiki/Evolution_of_cephalopods

    The cephalopods were once thought to have evolved from a monoplacophoran-like ancestor [8] with a curved, tapering shell, [9] and to be closely related to the gastropods (snails). [10] The similarity of the early shelled cephalopod Plectronoceras to some gastropods was used to support this view.

  6. Mollusc shell - Wikipedia

    en.wikipedia.org/wiki/Mollusc_shell

    An acidic shell matrix appears to be essential to shell formation, in the cephalopods at least; the matrix in the non-mineralized squid gladius is basic. [ 25 ] In oysters and potentially most molluscs, the nacreous layer has an organic framework of the protein MSI60, which has a structure a little like spider silk and forms sheets; [ 23 ] the ...

  7. Cuttlebone - Wikipedia

    en.wikipedia.org/wiki/Cuttlebone

    Cuttlebone, also known as cuttlefish bone, is a hard, brittle internal structure (an internal shell) found in all members of the family Sepiidae, commonly known as cuttlefish, within the cephalopods. In other cephalopod families it is called a gladius. Cuttlebone is composed primarily of aragonite.

  8. Find Out Why These Octopuses Throw Things at Each Other - AOL

    www.aol.com/why-octopuses-throw-things-other...

    The octopuses seen in the videos threw silt, shells, and algae at other nearby octopuses. To do so, they gathered up the debris underneath their bodies using their arms.

  9. Siphuncle - Wikipedia

    en.wikipedia.org/wiki/Siphuncle

    Only cephalopods with chambered shells have siphuncles, such as the extinct ammonites and belemnites, and the living nautiluses, cuttlefish, and Spirula. In the case of the cuttlefish, the siphuncle is indistinct and connects all the small chambers of that animal's highly modified shell; in the other cephalopods it is thread-like and passes ...