Researchers have discovered traces of microbial life in a rock formation in India dated to 3.5 billion years ago.
The study identifies this as the oldest directly dated rock with a confirmed biosignature, according to the authors.
The samples come from the Kolar Schist Belt in Karnataka, a region known for ancient volcanic and sedimentary rocks.
Scientists analyzed carbonaceous material within the rock using high-resolution imaging and isotopic analysis.
The carbon isotope ratios and microscopic structures are consistent with biological origin rather than abiotic processes.
Previous claims of early life have often relied on indirect dating or contested biosignatures; this study emphasizes direct dating of the host rock.
The findings push back the confirmed record of life on Earth and provide a new reference point for studying early habitability.
Researchers note that further work is needed to characterize the metabolic pathways of these ancient microbes.
Indian rock yields oldest directly dated traces of microbial life: study
This is an independent summary. The complete reporting, supporting context and any primary documents remain with The Hindu.