This can occur, for example, just after a planula larva has settled, metamorphosed, and secreted a skeleton. The bail out occurs in response to poor conditions, such as poorly oxygenated water. This photograph of a patch reef shows the complexity of species coexistence, even if we cannot exactly identify all of the species. As discussed in the text, coral competitive interactions are diverse and result in a good deal of complexity in the outcome of competition and succession. This shot was taken on a coral reef in the Grenadine Islands, Caribbean Sea.
Jacks are swift-swimming carnivores, usually feeding on other fish.
These polychaetes secrete a calcareous tube and have a crown of ciliated tentacles that collect particles from the water column. The worm has a conical operculum that can seal off the tube when the worm withdraws. You can see from above the fleshy parts of the so-called killer clam. Tridacna species are bivalves that maintain an exquisite symbiosis with algae known as zooxanthellae. These microorganisms, dinoflagellates actually, also occur in many other groups including corals and sea anemones.