Scientists discovered 2-billion-year-old microbes in a rock

Key takeaways:

1. Scientists from the University of Tokyo discovered two-billion-year-old microbes in South African rock deposits, breaking the record for the oldest known living microbes.
2. These ancient microbes have remained largely unchanged due to extreme isolation, offering a glimpse into early Earth’s life and evolutionary processes.
3. The Bushveld Igneous Complex’s stable, clay-rich environment created a perfectly sealed habitat, preserving these microbes for billions of years.
4. This discovery fuels the possibility of ancient life on Mars, especially as NASA’s data suggests the Red Planet had water around two billion years ago.
5. The successful identification of Earth’s ancient microbes raises hopes for finding similar life forms when Martian rock samples are brought to Earth, possibly in the 2040s.

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Scientists revive 2-billion-year-old microbes, offering a rare glimpse into early Earth.

Researchers from the University of Tokyo have uncovered a rare and unprecedented discovery—two-billion-year-old microbes that have survived in extreme isolation within rock deposits. Found in the Bushveld Igneous Complex in northeastern South Africa, these microbes represent the oldest known living organisms, offering a unique look into life on early Earth. The findings, published in Microbial Biology, could also provide clues in the search for life on other planets, particularly Mars.

A Time Capsule in Rock

The Bushveld Igneous Complex, a rock formation formed by ancient magma cooling beneath the Earth’s surface, has long intrigued geologists for its mineral-rich composition. In this study, researchers examined a 30-centimeter core sample from this formation, located 15 meters below ground, and discovered that its dense clay structure had protected the microbes from contamination and external influences. The clay sealed the microbes inside the rock, preventing any exchange of materials and effectively preserving the tiny organisms for billions of years.

To confirm the authenticity of the sample, the team employed a multi-step validation process. First, they used optical photothermal infrared (O-PTIR) spectroscopy to detect the microbes. Next, the microbes were stained with a green dye and analyzed using both scanning electron microscopy and fluorescent microscopy. This thorough process validated the age and isolation of the microbes, confirming that they had indeed been locked in the rock for two billion years.

Implications for Earth and Mars

This discovery not only expands knowledge about the history of life on Earth but also carries exciting implications for extraterrestrial research. Yohey Suzuki, the study’s lead author, emphasized the significance of finding such ancient life forms, as they offer insights into how early organisms evolved and adapted to extreme conditions. “Until now, the oldest geological layer in which living microorganisms had been found was a 100-million-year-old deposit beneath the ocean floor,” Suzuki noted, calling this new discovery “a very exciting development.”

The study’s implications extend beyond Earth. Recent findings by NASA’s Mars Reconnaissance Rover suggest that liquid water may have flowed on Mars as recently as 2 to 2.5 billion years ago. Since microbial life survived under similar conditions on Earth, scientists speculate that similar life forms might be locked in Martian rocks. With NASA’s Perseverance Rover currently collecting samples of Mars rock estimated to be around two billion years old, Suzuki and his team are hopeful that future analyses might reveal traces of ancient life on Mars as well.

Although a return of Martian soil to Earth is not expected until around 2040, this discovery adds new credibility to the search for life beyond our planet. According to Suzuki, these ancient microbes on Earth could mirror any potential life forms on Mars. By understanding these ancient microbes’ structure and environment, researchers could better predict and recognize signs of life in Martian samples.

In short, these ancient microbes not only deepen our understanding of early Earth but also hint at the possibility of life in similar environments beyond Earth, sparking hope for groundbreaking discoveries in future Martian exploration.