Coral reefs
11 questions tagged Coral reefs — spanning every one of the seven Ws.
Why do coral reefs bleach when the water gets too warm?
Heat stress makes corals expel the symbiotic algae they rely on for food and color, so the white limestone skeleton shows through. If stressful conditions last too long, the coral can die.
What is an atoll?
An atoll is a ring-shaped coral island or reef that surrounds a lagoon. It usually forms after a volcanic island sinks or erodes away.
When was the first scientific description of coral bleaching published?
One of the earliest clear scientific descriptions of coral bleaching was published in 1911. Modern large-scale bleaching was later linked to unusually warm sea temperatures.
Which ocean is the largest coral reef ecosystem in the world found in?
The Great Barrier Reef lies in the Coral Sea, part of the South Pacific Ocean. It is the world’s largest coral reef system, stretching about 2,300 km.
Which coral species forms one of the largest marine colonies?
The giant coral colony off the coast of West Papua, Indonesia, is one of the largest known coral colonies. It is a Pavona coral spread over more than 30 meters across and thousands of years old.
Which coral reef is the largest in the Atlantic Ocean?
The Mesoamerican Barrier Reef is the largest reef system in the Atlantic Ocean. It stretches about 1,000 kilometers along the coasts of Mexico, Belize, Guatemala, and Honduras.
Whose study first described the role of zooxanthellae in building coral reefs?
The German scientist Theodor Mortensen helped develop early coral biology, but the key role of symbiotic algae was established in the 19th century by zoologist Johannes Müller and later researchers. Coral reefs depend on this partnership for growth and color.
Why do some coral reefs bleach when the water gets too warm?
Corals bleach when heat stresses the tiny algae living in their tissues, causing the corals to expel them. Those algae provide most of the coral’s food and color, so prolonged bleaching can kill reefs.
Which coral builds the largest living structure on Earth?
The Great Barrier Reef is the largest living structure on Earth, stretching for about 2,300 kilometers off Australia’s northeast coast.
Whose research first revealed that coral reefs are built by tiny animals, not plants?
The animal nature of corals was established by 18th- and 19th-century naturalists and zoologists. They showed that corals are colonies of animals that secrete calcium carbonate skeletons.
How do coral reefs build up into huge underwater structures?
Tiny coral polyps secrete calcium carbonate skeletons, and generations of polyps build on top of older skeletons over centuries or millennia.