Re: antiquity of segmentation

[Matt Fraser <mattf+@xxxxxxxx>]

On Wed, 14 May 1997, Bill Shear wrote:

> Last week a very exciting and interesting article and commentary appeared
> in SCIENCE showing the possible homology of segmentation genes in
> arthropods and chordates. DiRobertis, in a commentary, proposed that
> segmentation therefore would have to have been a property of the common
> ancestor of protostomes and deuterostomes.  He went on to list a number
> other properties this hypothetical ancester would have to have had,
> suggesting that it would have been much more complex than originally
> envisioned.
> 
> Has anyone else been following this work?  Have the relevant genes been
> searched for in, for instance, echinoderms or hemichordates?

I haven't followed the work, but I would be surprised if they were or
would be found in echinoderms, given the radial symmetry. Although I guess
that one could argue for "radial segmentation".

Matt

  _________________________________________________________

Matt Fraser
mattf+@pitt.edu
Matt's Paleo Pages <http://www.pitt.edu/~mattf/PaleoPage.html>

                     Where you can find
 The Paleo Award, PaleoNews, PaleoChat, The Paleo Forum, and
                   The Paleo Ring Webring!

                 *Member of The Paleo Ring*

  _________________________________________________________