The Great Barrier Reef is one of Earth’s 7 natural wonders. We’re wondering if you’ll be a natural at this quiz! Wade into the Reef’s fantastic ecology and aim for a dive out of five.

#1. The Great Barrier Reef is the world’s biggest continuous living structure. About how long does the Great Barrier Reef stretch?

Located in the Coral Sea just off the coast of Queensland, the Great Barrier Reef stretches over 2,300 kilometres and takes up an area of about 344,400 square kilometres.

#2. The Great Barrier Reef is built by billions of tiny organisms called coral polyps. Coral polyps belong to which group of living things?

Coral are marine invertebrates, meaning they are sea animals that don’t have a backbone. They are closely related to sea anemones and are in the same large group (phylum) as jellyfish.

#3. True or false? The Great Barrier Reef can be seen from space.

True. Space agencies including NASA have photographed the Reef from space. Reefs are easy to spot from space because the shallow water looks light blue, and it contrasts sharply with the dark blues of deeper water.

#4. Rising sea temperatures threaten the Reef because the high temperatures stress the corals. What colour do stressed corals turn?

Healthy corals are home to colourful organisms called zooxanthellae. But when sea temperatures rise, stressed corals kick out the zooxanthellae, revealing the coral’s white colour. This process is called coral bleaching and it’s a major threat to the Reef.

#5. Which of the following animals eats large amounts of coral polyps, damaging the Reef?

The crown-of-thorns starfish kills and eats coral polyps, and they’re one of the biggest threats to the reef. Scientists keep inventing new ways to fight them, including AI controlled anti-starfish submarines!

Was I right?


Congratulations! You are a real science whiz!

Oh dear! Better brush up before the next quiz!

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