Coral Reef Island – Miles Bridge

A coral reef is an underwater ecosystem characterized by reef-building corals. Reefs are formed of colonies of coral polyps held together by calcium carbonate.  Most coral reef island are built from stony corals, whose polyps cluster in groups.  Most reefs grow best in warm, shallow, clear, sunny and agitated water.  They are most commonly found at shallow depths in tropical waters, but deep water and cold-water coral reefs exist on smaller scales in other areas.  Most reefs grow best in warm, shallow, clear, sunny and agitated water. Coral reef island first appeared 485 million years ago, at the dawn of the Early Ordovician, displacing the microbial and sponge reefs of the Cambrian.  Reefs are formed of colonies of coral polyps held together by calcium carbonate.  Most coral reef island grow best in warm, shallow, clear, sunny and agitated water.  Sometimes called rainforests of the sea, shallow coral reefs form some of Earth’s most diverse ecosystems. They occupy less than 0.1% of the world’s ocean area, yet they provide a home for at least 25% of all marine species, including fish, mollusks, worms, crustaceans, echinoderms, sponges, tunicates and other cnidarians. They are most commonly found at shallow depths in tropical waters, but deep water and cold-water coral reefs exist on smaller scales in other areas.  Most coral reef island were formed after the Last Glacial Period when melting ice caused sea level to rise and flood continental shelves. Most coral reefs are less than 10,000 years old. As communities established themselves, the reefs grew upwards, pacing rising sea levels. Reefs that rose too slowly could become drowned, without sufficient light.^[15] Coral reefs are found in the deep sea away from continental shelves, around oceanic islands and atolls. The majority of these islands are volcanic in origin. Others have tectonic origins where plate movements lifted the deep ocean floor.  As the name implies, coral reefs are made up of coral skeletons from mostly intact coral colonies.