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'''Animalia''' is the taxonomic kingdom comprising all animals (including human beings).

'''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.

==References==
{{Reflist|colwidth=25em}}

===Bibliography===
* Klaus Nielsen. ''Animal Evolution: Interrelationships of the Living Phyla'' (2nd edition). Oxford University Press, 2001.
* Knut Schmidt-Nielsen. ''Animal Physiology: Adaptation and Environment''. (5th edition). Cambridge University Press, 1997.

==External links==
{{Sister project links|Animalia}}
* {{eol|1}}
* [http://tolweb.org/ Tree of Life Project]
* [http://animaldiversity.ummz.umich.edu/site/index.html Animal Diversity Web] – University of Michigan's database of animals, showing taxonomic classification, images, and other information.
* [http://www.arkive.org ARKive] – multimedia database of worldwide endangered/protected species and common species of UK.
* [http://www.sciam.com/article.cfm?chanID=sa006&articleID=000DC8B8-EA15-137C-AA1583414B7F0000 Scientific American Magazine (December 2005 Issue) – Getting a Leg Up on Land] About the evolution of four-limbed animals from fish.