Skip Navigation


Integrative and Comparative Biology Advance Access originally published online on May 22, 2007
Integrative and Comparative Biology 2007 47(5):770-785; doi:10.1093/icb/icm027
This Article
Right arrow Full Text Freely available
Right arrow FREE Full Text (PDF) Freely available
Right arrow All Versions of this Article:
47/5/770    most recent
icm027v1
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 Extavour, C. G. M.
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.

Evolution of the bilaterian germ line: lineage origin and modulation of specification mechanisms

Cassandra G. M. Extavour1,2,*
*Department of Zoology, University of Cambridge, Downing Street, Cambridge, Cambridgeshire, CB2 3EJ, England

Correspondence: 1E-mail: cgme2{at}hermes.cam.ac.uk

A key focus of evolutionary developmental biology (evo–devo) in recent years has been to elucidate the evolution of developmental mechanisms as a means of reconstructing the hypothetical last common ancestors of various clades. Prominent among such reconstructions have been proposals as to the nature of the mysterious "Urbilateria," originally defined as the last common ancestor of the extant Bilateria (protostomes and deuterostomes). Indeed, drawings of this animal can now be found, as well as detailed information on the genetics and morphological processes that it used to construct its gut, heart, eyes, appendages, segments, and body regions. Perhaps surprisingly, however, no explanations have yet been offered as to how this animal might have achieved the successful reproduction that must have been necessary for it to give rise to those lineages that are ancestral to today's diverse clades. The present article examines the comparative data available to date on the specification of the only cells containing the genetic hereditary material, the germ cells, and speculates on the possible evolutionary and developmental origin of the Urbilaterian germ line.

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

2Present address: Department of Organismic and Evolutionary Biology, Harvard University, BioLabs Building, 16 Divinity Avenue, Cambridge MA, 02138, U.S.A.


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
 Cold Spring Harb Symp Quant BiolHome page
P.A. Newmark, Y. Wang, and T. Chong
Germ Cell Specification and Regeneration in Planarians
Cold Spring Harb Symp Quant Biol, November 6, 2008; (2008) sqb.2008.73.022v1.
[Abstract] [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.