Cyanobacteria, which emerged around 2.9 billion years ago, are considered the first oxygen producers. However, despite their active photosynthesis, the accumulation of oxygen in the atmosphere did not begin until hundreds of millions of years later. Previously, scientists explained this by the fact that oxygen was bound to rocks as a result of various chemical reactions.
However, new research suggests that living organisms may also have played an important role in this process. An analysis of genetic sequences from thousands of modern species allowed researchers to reconstruct the evolutionary history of aerobic respiration enzymes. The results of the study indicate that soon after the emergence of cyanobacteria, other microorganisms began to actively use oxygen, thereby preventing its accumulation in the atmosphere.
Fatima Hussain, a co-author of the study, emphasized that these results change our understanding of the development of life on our planet and indicate how early organisms began to adapt to the use of oxygen.
Previously, researchers also reported on the possible natural formation of RNA molecules approximately 4.3 billion years ago. An international group of scientists described a six-stage process of RNA synthesis from simple organic compounds without external interventions. These findings were published in the journal PNAS.
