Skip Navigation


Integrative and Comparative Biology Advance Access originally published online on June 1, 2007
Integrative and Comparative Biology 2007 47(5):693-700; doi:10.1093/icb/icm041
This Article
Right arrow Full Text Freely available
Right arrow FREE Full Text (PDF) Freely available
Right arrow All Versions of this Article:
47/5/693    most recent
icm041v1
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in ISI Web of Science
Right arrow Alert me to new issues of the journal
Right arrow Add to My Personal Archive
Right arrow Download to citation manager
Right arrow Search for citing articles in:
ISI Web of Science (4)
Right arrow Request Permissions
Google Scholar
Right arrow Articles by Boero, F.
Right arrow Articles by Piraino, S.
Right arrow Search for Related Content
Social Bookmarking
Add to CiteULike   Add to Connotea   Add to Del.icio.us  
What's this?

© The Author 2007. Published by Oxford University Press on behalf of the Society for Integrative and Comparative Biology. All rights reserved. For permissions please email: journals.permissions@oxfordjournals.org.

Cnidarian milestones in metazoan evolution

Ferdinando Boero1,*, Bernd Schierwater{dagger} and Stefano Piraino1,*
*Dipartimento di Scienze e Tecnologie Biologiche ed Ambientali DISTEBA, Università del Salento, I-73100 Lecce;
{dagger}ITZ, Ecology & Evolution, TiHo Hannover, Bünteweg 17d, D-30559 Hannover; {dagger}American Museum of Natural History, New York, Division of Invertebrate Zoology, 79th Street at Central Park West, New York, NY 10024, USA

Correspondence: 1E-mail: boero{at}unile.it

Cnidarians display most of the characters considered as milestones of metazoan evolution. Whereas a tissue-level organization was probably already present in the multicellular common ancestor of all animals, the Urmetazoa, the emergence of important animal features such as bilateral symmetry, triploblasty, a polarized nervous system, sense organs (eyes, statocysts), and a (chitinous or calcium-based) continuous skeleton can be traced back before the divergence between cnidarians and bilaterians. Modularity and metamery might be also regarded as two faces of the same medal, likely involving conserved molecular mechanisms ruling animal body architectures through regional specification of iterated units. Available evidence indicates that the common ancestor of cnidarians and bilaterians, the UrEumetazoa, was a surprisingly complex animal with nerve cell differentiation. We suggest that paedomorphic events in descendants of this ancestor led to the array of diversity seen in the main extant animal phyla. The use of molecular analyses and identifying the genetic determinants of anatomical organizations can provide an integrative test of hypotheses of homologies and independent evidence of the evolutionary relationships among extant taxa.

From the symposium "Key Transitions in Animal Evolution" presented at the annual meeting of the Society for the Integrative and Comparative Biology, January 3–7, 2007, in Phoenix, Arizona.


Add to CiteULike CiteULike   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us    What's this?


This article has been cited by other articles:


Home page
 Phil Trans R Soc BHome page
J. Baguna, P. Martinez, J. Paps, and M. Riutort
Back in time: a new systematic proposal for the Bilateria
Phil Trans R Soc B, April 27, 2008; 363(1496): 1481 - 1491.
[Abstract] [Full Text] [PDF]


Disclaimer: Please note that abstracts for content published before 1996 were created through digital scanning and may therefore not exactly replicate the text of the original print issues. All efforts have been made to ensure accuracy, but the Publisher will not be held responsible for any remaining inaccuracies. If you require any further clarification, please contact our Customer Services Department.