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


     

Biol Bull 144: 64-72. (February 1973)
© 1973 Marine Biological Laboratory
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 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 FRANCIS, L.
Right arrow Search for Related Content
PubMed
Right arrow Articles by FRANCIS, L.

CLONE SPECIFIC SEGREGATION IN THE SEA ANEMONE ANTHOPLEURA-ELEGANTISSIMA

LISBETH FRANCIS 1

1 Biology Department, University of California, Santa Barbara, California, 93106

The anemones in a single continuous aggregation of the sea anemone Anthopleura elegantissima are observed to resemble each other in two obvious ways: (1) all have the same color pattern, and (2) all individuals having developed gonads are of the same sex. Furthermore, while sustained contact between individuals within an aggregation is very common, contact between individuals from different aggregations has been found to initiate an intraspecific aggressive response resulting in the separation of these individuals (Francis, 1973). These animals are known to reproduce asexually by longitudinal fission, and it is therefore concluded that the aggregations must each be comprised of anemones from a single clone. It seems to me improbable that anything other than genetic identity could account for aggregations of up to thousands of individuals of the same sex, having the same color patterns and showing mutual tolerance for contact with each other and for no other members of the species.

Even among anemones within a single clone, the presence of gonads containing gametes is shown to be related to size. Anemones smaller than 0.2 g dry wt consistently lack developed gonads, while some proportion of those over 0.2 g have gonads with gametes.

In the field, adjacent clonal groups are observed to remain separated from each other. In the laboratory a mixed group of anemones will reaggregate into isolated uniclonal groups, implying that clone specific segregation is actively accomplished by the anemones.

Living in aggregations has a number of potential advantages for the anemones such as reducing their effective surface area and thereby reducing water loss and the battering effects of wave action, excluding interspecific competition for space by promoting effective blanketing of an area, and allowing for cooperation in the capture and holding of larger prey. The function for the anemones of clone specific segregation and separation is not yet clear (see Francis, 1973), however the phenomenon is not without parallel since some other coelenterates as well as some bryozoans have also been observed to respond differently to contact with a genetically identical conspecific than to contact with other conspecifics.




This article has been cited by other articles:


Home page
 Integr. Comp. Biol.Home page
J. B. Geller, L. J. Fitzgerald, and C. E. King
Fission in Sea Anemones: Integrative Studies of Life Cycle Evolution
Integr. Comp. Biol., August 1, 2005; 45(4): 615 - 622.
[Abstract] [Full Text] [PDF]

Home page
 Biol. Bull.Home page
L. Francis
Microscaling: Why Larger Anemones Have Longer Cnidae
Biol. Bull., October 1, 2004; 207(2): 116 - 129.
[Abstract] [Full Text] [PDF]

Home page
 ScienceHome page
N. Howe and Y. Sheikh
Anthopleurine: a sea anemone alarm pheromone
Science, August 1, 1975; 189(4200): 386 - 388.
[Abstract] [PDF]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Copyright © 1973 by the Marine Biological Laboratory.