Scientists have discovered the cause of a mass extinction of sea-floor marine organisms 800,000 years ago. They tested various possible causes and were able to discount others such as ocean cooling. They discovered that it was caused by a global change in plankton at the surface of the ocean

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Scientists have discovered the cause of a mass extinction of sea-floor marine organisms 800,000 years ago. They tested various possible causes and were able to discount others such as ocean cooling. They discovered that it was caused by a global change in plankton at the surface of the ocean