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The Formation of Coral Reefs

Coral reefs are often called the "rainforests of the sea" due to their incredible biodiversity. These underwater structures are built by tiny animals known as coral polyps. Polyps live in colonies and secrete calcium carbonate to form a hard, protective skeleton. Over thousands of years, these skeletons accumulate, creating the massive and complex formations we recognize as coral reefs. They are one of the oldest and most diverse ecosystems on the planet.

The survival of coral reefs depends on a delicate balance of specific environmental conditions. Most reef-building corals thrive in warm, clear, and shallow tropical or subtropical waters where sunlight can penetrate. Sunlight is crucial because corals have a symbiotic relationship with algae called zooxanthellae, which live within their tissues. These algae perform photosynthesis, providing the corals with essential nutrients. Without adequate sunlight, the algae cannot survive, and in turn, the coral polyps cannot sustain themselves.

Despite their importance, coral reefs face numerous threats, many of which are human-induced. Rising sea temperatures can cause coral bleaching, a process where corals expel their symbiotic algae, turning them white and vulnerable to disease. Pollution from land, such as agricultural runoff, and destructive fishing practices also damage these fragile ecosystems. The preservation of these vibrant underwater cities is a critical environmental challenge that requires global cooperation and immediate action.