Biol. Bull. Sign up for etocs!
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

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 Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Gibson, G. D.
Right arrow Articles by Harvey, J. M.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Gibson, G. D.
Right arrow Articles by Harvey, J. M.

The Biological Bulletin, Vol 199, Issue 1 41-49, Copyright © 2000 by Marine Biological Laboratory

JOURNAL ARTICLE

Morphogenesis during asexual reproduction in Pygospio elegans Claparede (Annelida, Polychaeta)

GD Gibson and JM Harvey
Department of Biology, Acadia University, Wolfville, Nova Scotia, Canada. glenys.gibson@acadiau.ca

The spionid Pygospio elegans reproduces both asexually and sexually. Using scanning electron and bright field microscopy, we examined morphogenesis following asexual reproduction to determine how "lost" body regions were regenerated after a worm spontaneously divided. Asexual reproduction occurred through transverse fission and divided the parent worm into 2 to 6 fragments (architomy). All fragments retained their original anterior-posterior polarity. Regeneration in all fragments followed a specific series of events: wound healing (day 1); extension of the blastema to generate lost body regions-specifically, the head and thorax for posterior fragments and the tail and pygidium for anterior fragments (days 2-3); segmentation (days 3-6); and differentiation of segment- or region-specific structures (days 4-8). This pattern occurred regardless of where the original division took place. Subsequent growth occurred through addition of terminal setigers anterior to the pygidium followed by differentiation of tail setigers into abdominal setigers, leaving the tail region about 6 to 10 setigers in size. Division rates were compared in worms from three populations in Nova Scotia, Canada. Worms from two populations (Conrad's Beach, Starr's Point) divided more frequently (about 1.2 and 1.3 weeks between divisions, respectively) than worms from Bon Portage Island (3.5 weeks between divisions). Fragments containing the original head (original mouth intact, generally much larger fragment) had a higher survivorship than fragments containing the original tail.


This article has been cited by other articles:


Home page
 Biol. Bull.Home page
D. G. MCCurdy
Asexual Reproduction in Pygospio elegans Claparede (Annelida, Polychaeta) in Relation to Parasitism by Lepocreadium setiferoides (Miller and Northup) (Platyhelminthes, Trematoda)
Biol. Bull., August 1, 2001; 201(1): 45 - 51.
[Abstract] [Full Text] [PDF]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Copyright © 2000 by the Marine Biological Laboratory.