Skip Navigation

American Zoologist 1994 34(3):353-363; doi:10.1093/icb/34.3.353
© 1994 by The Society for Integrative and Comparative Biology
This Article
Right arrow Full Text (PDF)
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 Alert me to new issues of the journal
Right arrow Add to My Personal Archive
Right arrow Download to citation manager
Right arrow Request Permissions
Google Scholar
Right arrow Articles by WRAY, G. A.
Right arrow Search for Related Content
Social Bookmarking
Add to CiteULike   Add to Connotea   Add to Del.icio.us  
What's this?

The Evolution of Cell Lineage in Echinoderms1

GREGORY A. WRAY
Department of Ecology and Evolution, State University of New York Stony Brook, New York 11794

SYNOPSIS. Metazoan embryos in various phyla and classes often utilize quite different processes to specify cell fates during embryogenesis. These differences have been interpreted either as constraints, necessary for fabricating distinct adult body plans, or as adaptations for particular life history strategies. This paper analyzes the evolution of echinoderm cell lineage within a phylogenetic context as a means of testing these hypotheses. Several features of echinoderm cell lineage are probably over 550 million years old, and have persisted despite extensive transformations in adult morphology. Other features are much more variable evolutionarily, and have changed on many separate occasions. Importantly, even some of the most ancient and conservative features of echinoderm cell lineage can still evolve. These transformations are correlated with a particular life history transformation, the switch from feeding to nonfeeding larvae. The results suggest that adaptation has played a significant role in the evolution of cell lineage in echinoderms: some ancient features have been maintained for functional reasons rather than because of constraints, and some derived features have evolved in response to particular environmental challenges.


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




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.