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

Other articles related to "animal, animals":

Animal - Ethics
... Animals are regarded by philosophers like Peter Singer as ethical subjects ... Animal rights movements have worked to promote animal welfare ...
Animal Behaviour
... Animal behaviour is the subject of The field of ethology Animal Behaviour, a scientific journal ...
Walter Burkert - Burkert's Theory of Sacrificial Ritual
... Salted-barley corns from the basket were thrown on the animal’s head and into the altar fire ... A lock of hair from the animal is then cut and burned, libation being poured on the altar with prayer ... After silence is proclaimed, the music of flutes begins and the animal is slain ...
Monkey - Relationship With Humans - In Experiments
... the Rhesus Macaque, and African Green Monkeys are widely used in animal testing facilities, either wild-caught or purpose-bred ... Animal rights activists claim that their use is cruel and produces little information of value, and there have been many protests, vandalism to testing facilities and ... The topic has become a popular cause for animal rights and animal welfare groups ...
Nalgene - Controversy
... In 1997 Nalgene was targeted in a nationwide boycott by campus-based animal rights activists for products used in animal experimentation ... research "conducted only within the guidelines of the federal Animal Welfare Act and only when necessary." ...

Famous quotes containing the word animal:

    ‘Tis said that courage is common, but the immense esteem in which it is held proves it to be rare. Animal resistance, the instinct of the male animal when cornered, is no doubt common; but the pure article, courage with eyes, courage with conduct, self-possession at the cannon’s mouth, cheerfulness in lonely adherence to the right, is the endowment of elevated characters.
    Ralph Waldo Emerson (1803–1882)

    O animal excellence,
    Take pterodactyl flight
    Fire-winged into the air
    And find your lair
    With cunning sense
    On some Arabian bight....
    Allen Tate (1899–1979)

    Man, became man through work, who stepped out of the animal kingdom as transformer of the natural into the artificial, who became therefore the magician, man the creator of social reality, will always stay the great magician, will always be Prometheus bringing fire from heaven to earth, will always be Orpheus enthralling nature with his music. Not until humanity itself dies will art die.
    Ernst Fischer (1899–1972)