Coral

Coral are actually animals, not plants, since they do not make their own food. 

Most structures that we call "coral" are, in fact, made up of hundreds to thousands of tiny coral creatures called polyps, which secrete calcium carbonate. All the polyps in a colony are clones, genetically identical. 

Each polyp is a sac-like animal typically only a few millimetres in diameter and a few centimetres in height.

They are the largest structures of biological origin on Earth. 

Most structures that we call "coral" are, in fact, made up of hundreds to thousands of tiny coral creatures called polyps, which secrete calcium carbonate

In 1842 Charles Darwin has formulated the first accurate basic explanation of the origin of coral reefs in his The Structure & Distribution of Coral Reefs.

Coral reefs make up only 1% of the ocean floor, but are home to 25% of all ocean life.

Coral reefs support the most species per unit area of any of the planet’s ecosystems, rivaling rain forests.

Coral Reefs are the largest living structures on Earth — with some visible even from space.

Reefs such as The Great Barrier Reefs are called “barriers” when they run parallel to the coastline, in a way that they protect the shallow waters from the open sea.

In 2020, researchers discovered a coral reef in Australia’s Great Barrier Reef that measures more than 500 meters (1,640 feet). It was the first to be discovered in the Great Barrier Reef in more than 120 years.

The Black Sea Rod Coral contains large quantities of a lipid, prostaglandin A, which deters predatory fish from feeding on it by making them vomit.

14,000 tons of sunscreen are discharged into coral reefs each year, and a drop of it contains enough oxybenzone to disrupt coral growth.

Source Twistedsitter