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... Even the researchers running this giant experiment had their doubts as no visible progress was initially seen.
But beneath the surface, those scrapped shells immediately got to work" even though human eyes couldn't perceive it.

Bacteria began attaching themselves to the discarded shells, creating a biofilm, which is the starting point for pretty much all marine ecosystems on the planet. It's something scientists still struggle to recreate in a lab.

The shells also released calcium as they disintegrated, which produced "microzones," small, invisible pockets of water with a slightly different chemical makeup that certain underwater organisms need to survive.

Not only that, but the dead shells served as a solid foundation upon which living baby oysters could mount and grow. (Previously, due to reef decline, there were only soft surfaces.) The living oysters then filtered the water, keeping harmful algae blooms at bay.

All of these things and more helped revive fish, turtle, and dolphin populations to numbers not seen in over two and a half decades.

Layer by layer, the ocean floor had rebuilt itself until the results were visibly undeniable. ...