Radiata
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- For the tree, see Pinus radiata
{{Taxobox | color = pink | name = Radiata | image = Chrysaora jelly.jpg | image_caption = Chrysaora jellyfish | regnum = Animalia | subregnum = Eumetazoa | unranked_phylum = Radiata | unranked_phylum_authority = Linnaeus, 1758 | subdivision_ranks = Phyla | subdivision =
}}
The Radiata are the radially symmetric animals of the Eumetazoa subregnum. The term Radiata has had various meanings in the history of classification. It has been applied to the echinoderms, and to a larger group that included the echinoderms as well as various worms, coelenterates and protists. The radiata are also considered diploblastic, meaning they have 2 primary germ layers. Thomas Cavalier-Smith in 1983 defined a subkingdom called Radiata consisting of sponges, coelenterates and placozoans, that is, all the animals that are not in Bilateria. Cavalier-Smith's classification put the phyla Porifera, Myxozoa, Placozoa, Cnidaria and Ctenophora in Radiata. The Five Kingdom classification of Lynn Margulis and K. V. Schwartz keeps only Cnidaria and Ctenophora in Radiata. Cladistic classifications do not recognize Radiata as a clade.
Although radial symmetry is usually given as a defining characteristic of radiates, the free-swimming planula larvae of cnidarians exhibit bilateral symmetry, as do some adult cnidarians. Ctenophores show biradial symmetry.
References
- This article incorporates text from the Encyclopædia Britannica Eleventh Edition{{#if:{{{article|}}}| article {{#if:{{{url|}}}|[{{{url|}}}}} "{{{article}}}"{{#if:{{{url|}}}|]}}{{#if:{{{author|}}}| by {{{author}}}}}}}, a publication now in the public domain.
- Zoological Philosophy of J. B. Lamarck
- Taxon: Subkingdom Radiata
- The development of radial and biradial symmetry: The evolution of bilaterality - retrieved February 22006
- Origins of Bilateral Symmetry: Hox and Dpp Expression in a Sea Anemone - retrieved February 22006Template:Animal-stub
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