This is an amazing story..
Scientists have discovered that metallic nodules on the seafloor produce their own oxygen in the dark depths of the Pacific Ocean. These polymetallic nodules, generating electricity like AA batteries, challenge the belief that only photosynthetic organisms create oxygen, potentially altering our understanding of how life began on Earth.
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https://www.france24.com/en/americas/20240723-dark-oxygen-pacific-ocean-life-origins