one publication added to basket [248967] | A vanished history of skeletonization in Cambrian comb jellies
Ou, Q.; Xiao, S.; Han, J.; Sun, G.; Zhang, F.; Zhang, Z.; Shu, D. (2015). A vanished history of skeletonization in Cambrian comb jellies. Science Advances 1(6): 8 pp. http://dx.doi.org/10.1126/sciadv.1500092
In: Science Advances. AAAS: New York. e-ISSN 2375-2548, more
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Authors | | Top |
- Ou, Q.
- Xiao, S.
- Han, J.
- Sun, G.
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- Zhang, F.
- Zhang, Z.
- Shu, D.
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Abstract |
Ctenophores are traditionally regarded as “lower” metazoans, sharing with cnidarians a diploblastic grade of organization. Unlike cnidarians, where skeletonization (biomineralization and sclerotization) evolved repeatedly among ecologically important taxa (for example, scleractinians and octocorals), living ctenophores are characteristically soft-bodied animals. We report six sclerotized and armored ctenophores from the early Cambrian period. They have diagnostic ctenophore features (for example, an octamerous symmetry, oral-aboral axis, aboral sense organ, and octaradially arranged ctene rows). Unlike most modern counterparts, however, they lack tentacles, have a sclerotized framework, and have eight pairs of ctene rows. They are resolved as a monophyletic group (Scleroctenophora new class) within the ctenophores. This clade reveals a cryptic history and sheds new light on the early evolution of this basal animal phylum. Skeletonization also occurs in some other Cambrian animal groups whose extant members are exclusively soft-bodied, suggesting the ecological importance of skeletonization in the Cambrian explosion. |
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