Wonderful Corals and Coral reefs
Coral reefs represent some of the oldest and most complex communities of plants and animals on Earth. The primary structure of a coral reef is a calcareous skeleton formed by marine invertebrate organisms known as cnidarians, which are relatives of sea anemones.
There are essentially three types of coral reefs – fringing reefs, barrier reefs, and atolls. Fringing reefs form borders along the shoreline. Barrier reefs also parallel the shoreline but are found further offshore and are separated from the coast by a lagoon. The atoll is typically a ring-shaped reef.
About 33% of all of the fishes of the world live and depend on coral reefs. Within the reef, there are hiding places for fish and other marine organisms.
The largest coral reef in the world is the Great Barrier Reef near Australia. It is more than 1,250 miles long.
The first corals appeared about 300–500 million years ago. Corals are sea animals that stay in one place throughout their adult lives. At one end it has a mouth surrounded by little arms called “tentacles”, which gather food. The baby coral swims through the water until it finds a place to build its house, and then it never swims again.
Corals require clear water to flourish. They need as much light energy as possible so the algae in their tissues can thrive. The waves bring floating organic materials, oxygen, and nutrients to the corals. Corals prey on tiny planktonic organisms. Some corals paralyze their prey using stinging cells located on their tentacles. Other corals feed by creating weak water currents with cilia to draw food into their mouth.
To reproduce, corals produce eggs that develop into tiny, swimming creatures called planulae. Planulae eventually settle on a surface and develop into polyps. A single polyp can develop into a massive coral head through multiple budding episodes.
Coral reefs are being endangered by human activities and without coral reefs entire marine ecosystems may vanish.
– Coral reefs are sometimes called the rain forests of the sea.
– The first coral jewelries were made in ancient Sumerian civilization. Their age is more than six thousand years.
– A huge amount of calcium makes corals a unique cure for broken bones.
– Ancient healers knew how to make contraceptive drugs from coral powder.
– It has beneficial effects on blood circulation, memory, hearing and vision.
– The ancient Greeks believed that coral prolonged life.
– Coral is a talisman for travelers and explorers. It protects from hurricanes, fires and storms.