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How Do Coral Reefs Grow So Slowly Yet So Big?

How Do Coral Reefs Grow So Slowly Yet So Big?

珊瑚礁生长如此缓慢,为何却能变得如此巨大?

  1. Coral reefs grow only one to two centimeters each year.
  2. Tiny coral animals called polyps build hard calcium skeletons.
  3. New polyps grow on top of old skeletons over hundreds of years.
  4. Reefs also expand sideways as colonies spread slowly.
  5. Ocean currents bring food and clear away sand to help growth.
  6. Warm, clear, shallow water gives the best conditions for corals.
  7. Some reefs are over 5,000 years old and cover huge areas.
  8. They support more life than almost any other ocean habitat.
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