One 2 billion year old rock recently excavated by experts in South Africa. When they examined this rock, they were extremely surprised to discover microorganisms still alive in the rock, even growing well. This is the oldest example of living microorganisms ever found in ancient rock.
“We don’t know whether these rock Is 2 billion years old still suitable for life? Previously, the oldest geological layer where experts found living microorganisms was in a 100-million-year-old sediment layer discovered beneath the ocean floor. Therefore, the new discovery is very interesting,” said Yohey Suzuki, an expert from the University of Tokyo, lead author of the new study published in the journal Microbial Ecology.
According to expert Yohey, by studying the DNA and genomes of such microorganisms, scientists can understand the evolutionary process of living organisms in the early stages on Earth.
Microorganisms live in a closed crack ancient rockexcavated from the Bushveld Eruptive Complex – a body of intrusive rock that forms as magma cools below the Earth’s surface. This massive complex covers an area roughly the size of Ireland and contains some very large ore deposits, including about 70% of the world’s mined platinum. It has remained relatively intact since its formation, creating perfect conditions for ancient microorganisms to survive. Such creatures live deep below the Earth’s surface, evolve extremely slowly, and have extremely slow metabolisms. Thanks to that, they can survive for a long time in the newly discovered rock that was 2 billion years old.
Through the support of the International Continental Science Program (ICDP), the team drilled 15 meters deep to obtain a 30-cm rock core sample. Upon closer inspection, they discovered microbial cells living close together in cracks in the rock, separated from the outside environment by chambers filled with clay.
Microorganisms grow well in the cracks of a 2 billion year old rock sample. They were dyed blue by experts and sent for analysis. Photo: Y. Suzuki, SJ Webb, M. Kouduka et al. 2024/ Microbial Ecology. |
To confirm that the microorganisms originated from the rock sample and were not just introduced from drilling or testing, the team of experts stained their DNA and used infrared spectroscopy to observe the proteins inside the microorganisms. materials as well as proteins in the surrounding clay. This is the method they pioneered in 2020. Through this method, researchers determined that the microorganisms were alive and not newly invaded.
As the oldest living microorganisms ever found in rock samples, the new discovery has a huge impact. Expert Yohey said he is very interested in the existence of microorganisms under the surface, not only on Earth but also in the possibility of finding them on other planets.
According to expert Yohey, Martian rocks are often much older than the newly discovered specimen in South Africa, about 20 – 30 billion years old. “NASA’s Perseverance robot is preparing to bring rocks back to Earth that are similar in age to the rocks we used in new research. Finding living microorganisms in samples discovered on the blue planet from 2 billion years ago and being able to authenticate them makes me very excited about what can be found in the Martian samples,” said expert Yohey.
Invite readers to watch the video: The mystery of a thousand-year-old rock split in half as if cut by laser.