[Coral-List] Age of clones?

[Andrew Baker]

Dear Charles and Alina

I would just add that somatic mutations will accumulate over the lifespan
(whatever that might be) of a clone, changing the "genotype" in a slow (but
possibly significant) fashion over time. In fact, large, old colonies might
represent mosaics of multiple genotypes (there are a couple of papers by
Fautin and Buddemeier et al. in the Proceedings of the 6th International
Conference on Coelenterate Biology (published 1997) that discuss some of the
implications of this at length, but I can't remember offhand if they
discussed "lifespans" or not).

I think it's interesting to think of coral colonies in this way (as
"evolving clones"), but it surely complicates the notion of "lifespan". I
think it's probably another example of how standard "animal" models don't
apply to corals in straightforward ways. 

I'm sure there are some valuable lessons from the plant world that can be
applied to this conundrum, but I don't know what they are! Anyone out there
who can shed some light?

Andrew

___________________
Andrew C. Baker, Ph.D.
Assistant Professor
Division of Marine Biology and Fisheries
Rosenstiel School of Marine and Atmospheric Science
University of Miami
4600 Rickenbacker Cswy.
Miami, FL 33149, USA
Voice: +1 (305) 421-4642
Fax: +1 (305) 421-4600

-----Original Message-----
From: coral-list-bounces at coral.aoml.noaa.gov
[mailto:coral-list-bounces at coral.aoml.noaa.gov] On Behalf Of Szmant, Alina
Sent: Thursday, January 19, 2006 6:23 AM
To: Charles Delbeek; coral-list at coral.aoml.noaa.gov
Subject: RE: [Coral-List] Age of clones?

Hi Charles:
 
Your question revolves around the issue of whether you are specifying an age
of an isolate or the age of the actual genotype.
 
With single celled algae the age of the clone is defined from when that
single cell was isolated from it's neighbors and cleaned up.  The particular
cell would be only a few days old at most at time of isolation, but the age
of the genotype would be older.  Not sure if anyone has tried to age a
genotype in such cells.  When did the first cell with that particular set of
genetic characteristics come about from sexual reproduction?
 
When one "clones" a coral, you are taking a piece of an animal that could be
tens to thousands of years old.  Every coral colony starts from a sexual
planula, so the chronological age of the coral colony and every fragment
derived from it would be the settlement date of that planula.  Unless you
find a good way to age the donor colony, then all you can specify is how
long that genotype has been in culture (you can call that the age of the
clonal isolate, but recognize that is not the same thing as the age of that
genotype).
 
Hope I didn't confuse you.
 
Alina
 
________________________________

From: coral-list-bounces at coral.aoml.noaa.gov on behalf of Charles Delbeek
Sent: Wed 1/18/2006 9:49 PM
To: coral-list at coral.aoml.noaa.gov
Subject: [Coral-List] Age of clones?


We are getting ready to send out coral fragments and excess Entacmaea
quadricolor anemones and I have a question. When one talks about the age of
animals, how do you treat clones? For example, all the anemones we have
originated via fission from a handful of animals collected from Palau in
1980. So, are these anemones 26 years old ... or do you take their age from
when they split? The same question applies to corals, we have specimens
that we have been fragmenting for years, some of which were collected in
1978 ... so are the fragments that old? Obviously for corals, new polyps
are being produced and old ones die off, so these would not be almost 30
years old ... but genetically they are the same as the original polyps ..
or are they? With anemones, it would be different I think since the
original tissue is still there.

Dazed and confused in Hawaii....

Aloha!


J. Charles Delbeek M.Sc.
Aquarium Biologist III
Waikiki Aquarium
2777 Kalakaua Ave.
Honolulu, HI, USA 96815
www.waquarium.org

808-923-9741
808-923-1771 FAX