Corals the underground colonies of Isles in Andaman & Nicobar Islands – Andaman Tech
The coral is less elusive, and numerous species of it may be seen around the Islands, abundantly in fringing reefs on the westward side of the Islands and the channels where the waters are protected. The fascinating colors of the coral are imparted to it, not by the polyps that built this skeletal structure of Calcium Carbonate around themselves, but by the presence of brownish-yellow algae and the gaily colored decorative fish that always live in association with it.
Colonies may grow, with several generation of polyps, to heights of 4-5 m, as may be seen at Nancowry Bay, or at the South Cinque Island Bay. Over many generations, the colony thus creates a large skeleton characteristic of the species. Individual heads grow by asexual reproduction of polyps. Corals also breed sexually by spawning polyps of the same species release gametes simultaneously over a period of one to several nights around a full moon.