Growth & Expansion, what will happen?

[MUCHO REEF]

Based upon this thread,


http://www.reefcentral.com/forums/showthread.php?s=&threadid=729863&perpage=25&pagenumber=1

....which is an excellent thread to read, It will take some time, but read each page and then share your opinions in this thread on the question below. PLEASE SHARE WHY YOU FEEL THE WAY YOU DO in your reply.


Question !!!!!

Rock A

Is a large zoo colony that is collected and taken to a LFS. Lets say the rock is perfectly symetrical, the diameter of a plate. On this rock are 500 common orange zoas all tightly growing in a slightly smaller circle, also perfectly symetrical in the center of the rock. There is a 2 inch ring around the colony of zoas with bare rock showing. Basically I am saying there is room for 2 inches of growth to the outer edge of the rock.

Rock B

Is an equal size rock as the one above, completely symmetrical, I know, I know, you're saying no two rocks with 500 zoas alike are going to be completely symmetrical. But for the sack of the question, just play along as if this happened. Now on the second rock, there are indeed 500 polyps, just like Rock A, but they are all standing alone on the rock and not touching. Each polyp has room for growth and expansion. Both rocks were collected side by side in the wild and are placed next to each other in a stable, mature system with optimal conditions for rapid growth as we have all listed above and on previous pages.

Now from your own personal experience, or, based upon what you think will occur, which rock is going to completely cover the face of the rock the quickest, and why.

If you have a personal experience, please share it in specific details. Thanks.

Mucho

 

[jdieck]

Well my experience is that they always grow were I don't want them too. I know the question is not about it but it will be nice to find out a way to contain then though.

Well as zooas feed by opening fully and getting light unless both can open properly and intake as much flow then they will get similar growth, on the other hand if being packed prevent to open fully or receive similar amount of flow to feed I think the ones spread out might grow a bit faster.
Also on the packed ones there might be additional detritus accumulation, how will it affect the growth? if it is food then it may counteract the lesser light or lesser suspended food available.
In summary, try it and report back because I am only hypothesizing.

 

[MUCHO REEF]

All things being equal, both are fully expanding and receiving the appropriate amounts of lighting, current and flow.

Mucho

 

[jdieck]

Then they will gro the same.

 

[tekknoschtev]

Mucho, this is actually something that I've been meaning to experiment with when I get home one weekend. My plan was to take frags however and mount them on glass. I've actually got several sticky notes from when I woke up at 3 or 4 in the morning and groggily sketched out some plans.

Reading my notes (which would be difficult if you didnt know how to read halfawakestevian) I was going to make a few 10 polyped frags and mount them to a piece of glass each. On each piece of glass, then I was going to take another 10 polyp frag but split it into 10 individual polyps. So one piece of glass would contain one 10 polyped frags and 10 one polyp frags. Then over the course of the next weeks/months, I'd monitor with pictures and manual inspection how many new polyps sprouted from the 10 polyped frags and the 10 one polyp frags collectively.

Ugh, there's so much I have plans for to do on the weekends when I'm home with the tank(s) I just never seem to have time

My personal thoughts, based anecdotally on experience is that in your example, that the 500 single polyps given enough room for growth and expansion would produce a larger number overall of polyps than the 500 polyp colony. My feeling, in examples that large, are that the single polyped pieces have a greater surface area by which to sprout new babies. You have the circumference of the one large mass, or the circumference of each polyp collectively.

I have noticed in a few instances, without numbers to really back it up though, that if I'm trying to cover a rock with zoas, that spreading many smaller frags randomly about the rock yields a covered rock faster than the single large frag glued to a similar rock. Again, this is really far form scientific mostly due to the different qualities of the rocks I am using (agrocrete vs. nature made randomness) which is why in my initial thoughts doing so on a piece of glass would be ideal.

 

[maggiesaqsup]

Here is one experince of what I did I had a colony that I cut off 5 polyps and gluded to a frag disk side by side in a tight ring.One polyp fell off and floated off and fell on a large rock all by its self. Today, 8 weeks later the tight ring frag has grown 1 new polyp and the 1 single polyp that floated off attached to the rock and has 2 new polyps.Is this a one time thing I don't know.

 

[-Keith-]

My GUESS is B would cover the rock (become a confluent monolayer) more quickly.

This NOT based from any experience with zoas, but instead draws from an analogy with mammalian cell culture. Some types of mammalian cells grow to a confluent monolayer (a single cell layer thick covering all available space) and then stop proliferating. This behavior is called contact inhibition of growth since to achieve it cells that are not in contact with neighbors proliferate but when they contact their neighbors they stop. If one seeds a cluster of contact inhibited cell in a small region analogous to ROCK A, only those at the perimeter proliferate but if you break up the cluster analogous to Rock B, all cells proliferate and the area is cover much more quickly.

One can argue that the analogy between single mammalian cells and single polyps is not valid, perhaps so but - as requested by mucho- this is what I feel is the answer and why I feel it.

 

[MUCHO REEF]

Great points.

Anyone else with an opinion?


MUCHO

PS. yeah yeah I know it's an old thread, but I still want to engage the topic.

 

[Reef Bass]

I see your thought train Keith and appreciate your reasoning.

In my opinion, the polyps of Rock A would cover the empty space more quickly. They share their energy as a mat or colony with the coenenchyme between polyps and can get busy with bursts of rapid growth if so inclined.

Rock B is a collection of single polyps which may or may thrive on their own and don't have the energy and hence ability to rapidly divide, compared to that of the colonial mass of rock A polyps.

In my tanks rock A would do great and most of the polyps on rock B would melt away, being single. A small percentage would survive, so in a couple months there would be multiple isolated clumps of several polyps on rock B while rock A would be completely covered with polyps.

 

[SIR PATRICK]

Reading- will reply soon! Possibly not tonight though.....

 

[Jarred1]

Here is what I think, based on what I know about science so far is that rock B will grow faster because there are more polyps that have more surface area to grow on. Rock A will grow slower because only the outer edge of the colony can grow. I don't know if this will make since to you and if it doesn't I'll try and explain myself better.

 

[MUCHO REEF]

Reading- will reply soon! Possibly not tonight though.....

Looking forward to hearing from you SP.

 

[SIR PATRICK]

I am figuring the 2nd rock will grow more polyps, as there is much more parimeter are, as long as the mat is healthy.

Sometimes, when I see a rock full of polyps, with very erradic growth patterns, it raises a red flag. Maybe the rock used to be completely covered at one time? Maybe the open area are from die off/recession? Maybe they are still receading? If this is the case, after carefull inspection on the health of the mat, I would have to go with rock #1.

 

[MUCHO REEF]

Hmmmm...good stuff guys.