Cyanobacteria, considered the first oxygen producers, emerged around 2.9 billion years ago. However, despite their active photosynthesis, oxygen began to accumulate in the atmosphere only after a significant amount of time. Previously, scientists explained this process by stating that oxygen was bound to rocks during chemical reactions.
The new study emphasizes that living organisms may have also played an important role in this process. Analyzing genetic sequences from thousands of modern species allowed researchers to reconstruct the evolutionary history of aerobic respiration. The results show that soon after the emergence of cyanobacteria, other microorganisms began to actively consume oxygen, thereby preventing its accumulation in the atmosphere.
Fatima Hussain, one of the co-authors of the study, noted that these findings change our understanding of the development of life on our planet and demonstrate how early organisms began to adapt to oxygen.
Additionally, scientists previously reported on the possible natural formation of RNA molecules approximately 4.3 billion years ago. An international team of researchers described a six-step process for synthesizing RNA from simple organic compounds without external intervention, and the results of their work were published in the journal PNAS.
