Scientists Discover Earliest Evidence of Photosynthesis, Pushing Back Timeline of Life on Earth
WASHINGTON D.C. – A new study published in the Proceedings of the National Academy of Sciences (PNAS) reveals the earliest direct evidence of photosynthesis occurring on Earth, dating back 3.3 billion years. Researchers have identified molecular signatures within ancient rocks in South Africa indicating the presence of biological activity considerably earlier than previously confirmed.
The breakthrough centers on analyzing ancient sedimentary rocks from the Barberton Greenstone Belt in South Africa. Using a combination of advanced chemistry and machine learning, scientists were able to differentiate between biogenic – originating from living organisms – and abiogenic samples. The random forest model employed in the study classified the percentage of biogenic versus abiogenic samples, revealing traces of molecules associated with photosynthesis.
“This method of combining chemistry with machine learning has revealed biological clues about ancient life that were previously invisible,” explained Katie Maloney, an assistant professor at Michigan State University and a contributor to the study.The research is particularly significant as ancient life forms frequently enough leave limited physical evidence, frequently erased by geological processes over vast timescales. this new technique allows scientists to retrieve molecular clues that would otherwise remain hidden.
The findings push back the established timeline for the emergence of photosynthesis, a process crucial for life as we know it. Prior evidence suggested photosynthesis developed later in Earth’s history. This finding indicates life was not only present but actively altering the planet’s atmosphere much earlier than previously thought.
The implications of this research extend beyond understanding Earth’s past. The techniques developed could prove invaluable in the search for life on other planets,including Mars.
“This innovative technique helps us to read the deep time fossil record in a new way. This could help guide the search for life on other planets,” Maloney stated. The ability to detect faint chemical signatures of life,as demonstrated in this study,can be applied to analyze extraterrestrial samples,potentially revolutionizing the field of astrobiology. Future missions to Mars could utilize similar methods to analyze Martian rocks for evidence of past or present life.
