Origin of photosynthesis may go further back than estimates from 50 years ago
Excerpt from the March 18, 1967, issue of Science News
![cyanobacteria](https://i0.wp.com/www.sciencenews.org/wp-content/uploads/2017/03/021617_LH_50ya_main_free.jpg?fit=860%2C460&ssl=1)
SOLAR POWERED Ancient cyanobacteria, much like these modern-day ones, expelled oxygen into Earth’s atmosphere as a byproduct of photosynthesis, perhaps as early as 3.2 billion years ago.
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