Animal

Animal

Animals are a major group of multicellular, eukaryotic organisms of the kingdom Animalia or Metazoa. Their body plan eventually becomes fixed as they develop, although some undergo a process of metamorphosis later on in their life. Most animals are motile, meaning they can move spontaneously and independently. All animals are also heterotrophs, meaning they must ingest other organisms or their products for sustenance.

Most known animal phyla appeared in the fossil record as marine species during the Cambrian explosion, about 542 million years ago.

Read more about Animal:  Etymology, Characteristics, Origin and Fossil Record, Model Organisms, History of Classification, Ethics

Famous quotes containing the word animal:

    All the lies and evasions by which man has nourished himself—civilization, in a word—are the fruits of the creative artist. It is the creative nature of man which has refused to let him lapse back into that unconscious unity with life which charactizes the animal world from which he made his escape.
    Henry Miller (1891–1980)

    The animal is one with its life activity. It does not distinguish the activity from itself. It is its activity. But man makes his life activity itself an object of his will and consciousness. He has a conscious life activity. It is not a determination with which he is completely identified.
    Karl Marx (1818–1883)

    There is no mystery in the luminous lines
    Of that high, animal face
    The smile, sad, humouring and equal
    Blesses without obliging
    Loves without condescension;
    Denis Devlin (1908–1959)