Growing with gravity

[Tegridy Reef]

Hey reef to reef members i was wanting your guys in put on what you guys think on this subject. I notice some hydroponic system where they use gravity as an aid to help acceralte growth, so was thinking about seeing if that would effect coral growing to. So the question is what do u think would happen if you had to encrusted acropora frags and in the same tank grew one right side up and the other upside down with the light shinning from the bottom of the tank. Do u think the one upside dowm thats using gravity would branch quicker. I see acropora alot of the times encrsut a ton but have also noticed with chalice that they accelerat in growth when they are growing down and slower when they grow up something what do u guys think depending on answers i might conduct this experiment

 

[revhtree Verified Admin]

Interesting

 

[Randy Holmes-Farley Verified Community Expert]

FWIW, the pull of gravity in general is pretty small for organisms under seawater, and I expect any differences in a test will more reflect differences in lighting and flow.

 

[Randy Holmes-Farley Verified Community Expert]

https://www.tau.ac.il/lifesci/departments/zoology/members/ilan/documents/ProcRSocLond2002.pdf


https://www.ncbi.nlm.nih.gov/pubmed/11934363

The effect of gravity on coral morphology.
Meroz E1, Brickner I, Loya Y, Peretzman-Shemer A, Ilan M.
Author information

Abstract
Coral morphological variability reflects either genetic differences or environmentally induced phenotypic plasticity. We present two coral species that sense gravity and accordingly alter their morphology, as characterized by their slenderness (height to diameter) ratio (SR). We experimentally altered the direction (and intensity) of the gravitational resultant force acting along or perpendicular to the main body axis of coral polyps. We also manipulated light direction, in order to uncouple gravity and light effects on coral development. In the experiments, vertically growing polyps had significantly higher SR than their horizontal siblings even when grown in a centrifuge (experiencing different resultant gravitational forces in proximal and distal positions). Lowest SR was in horizontal side-illuminated polyps, and highest in vertical top-illuminated polyps. Adult colonies in situ showed the same pattern. Gravitational intensity also affected polyp growth form. However, polyp volume, dry skeleton weight and density in the various centrifuge positions, and in aquaria experiments, did not differ significantly. This reflects the coral's ability to sense altered gravity direction and intensity, and to react by changing the development pattern of their body morphology, but not the amount of skeleton deposited.

 

[Tegridy Reef]

Great info randy thanks for the info so my understanding it would just change the form of the coral, maybe making it branch more them to encrust. thanks for the info was very good im sure it would even enhanve the growth direction if u had flow going in the same direction but what i read seems like the growth rate is staying the same only thing that gets alteresd is the form of the coral