Video summary
Professor Brian Cox explains how the Earth developed an oxygen rich atmosphere.
The secret lies with an ancient group of organisms called cyanobacteria.
Around 2.4 billion years ago, these bacteria evolved an incredible ability to produce their own food using photosynthetic pigments.
A by-product of this process was oxygen, and the success of these pioneering organisms filled the atmosphere with oxygen.
This transformed our planet and allowed the development of more complex life, like plants and animals.
This clip is from the series Wonders of Life.
Teacher Notes
This clip could be used as a stimulus to discuss how the Earth's early atmosphere changed.
Students could discuss the conditions that must have been present for the bacteria to begin the process of photosynthesis.
This clip will be relevant for teaching Biology at KS3 and KS4/GCSE in England, Wales and Northern Ireland and SQA National 3/4/5 in Scotland.
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