Deep questions - Polyps, Zooxanthellae, and Stony Corals

[Sumo Reef]

A little preface to my question

So polyps are individual animals, separate from the corals themselves. Polyps not only house zooxanthellae but are the way corals interact with their environment by providing a means for the coral to eat food. Polyps secrete calcium carbonate underneath themselves inside the cup they reside in. There is a whole lot of chemistry going on in the calcification process which isn't what this post is about. I'm really wanting to understand the growth process at a high level.

If polyps deposit the skeleton of stony corals, are they the only depositor of the skeleton?

If so, then what process do the zooxanthellae that reside in the skin of SPS corals play in the process?

Can polyps leave one coral and host in another? Where do they go when they bail out?

Something that also came to mind during posing these questions - LPS corals do not have zooxanthellae that live outside of polyps. Is this more efficient?

:thinking-face:

This really has me interested in learning more. Please provide any links if you have any!

 

[Sumo Reef]

Interesting paper on polyp bail out signals.

https://link.springer.com/article/10.1007/s00338-020-01983-x

 

[Sumo Reef]

Another find - still nothing on how the zooxanthellae in the skin of SPS play a role in building a skeleton. Do they travel to the polyps?

https://agupubs.onlinelibrary.wiley.com/doi/full/10.1002/2016GC006536