2-billion-year-old rock home to living microbes

[Still Waters]

Pockets of microbes have been found living within a sealed fracture in 2-billion-year-old rock. The rock was excavated from the Bushveld Igneous Complex in South Africa, an area known for its rich ore deposits. This is the oldest example of living microbes being found within ancient rock so far discovered.

The team involved in the study built on its previous work to perfect a technique involving three types of imaging – infrared spectroscopy, electron microscopy and fluorescent microscopy – to confirm that the microbes were indigenous to the ancient core sample and not caused by contamination during the retrieval and study process. Research on these microbes could help us better understand the very early evolution of life, as well as the search for extraterrestrial life in similarly aged rock samples brought back from Mars.

https://www.u-tokyo.ac.jp/focus/en/press/z0508_00374.html

[Piney]

@Doc Socks Junior How many ecosystems have geologists and resource specialists wiped out licking rocks? 😬 

[Doc Socks Junior]

7 hours ago, Piney said:

@Doc Socks Junior How many ecosystems have geologists and resource specialists wiped out licking rocks? 😬 

Apparently quite a few, if one believes this study.

I gave it a quick once over.

Seems pretty thorough. I imagine the critters well-postdate 2 billion years old, but their continued existence for however long post clay mineral formation is impressive. I think.

I did somewhat recently take a slurp of an old salt lick. Honestly, having been baked in the sun and rain, it was less revolting than the rock salt hand samples in an introductory geology laboratory. One's mileage may vary.

[Abramelin]

@Alchopwn

You asked in my thread about the same topic, but - apparently - posted in the wrong section:

"what are these microbes even subsisting on? "

Well, from a hidden link in that post of mine:

Subsurface Microbial Colonization at Mineral-Filled Veins in 2-Billion-Year-Old Mafic Rock from the Bushveld Igneous Complex, South Africa

https://link.springer.com/article/10.1007/s00248-024-02434-8

Quote:

The metabolic activities of subsurface microbiomes are exceedingly slow under survival mode [5, 6], leading to an estimated turnover time ranging from several thousand to million years. Consistent with the long turnover time [7], sulfate-reducing bacteria Candidatus Desulforudis audaxviator endemic to the deep subsurface have undergone minimal evolution since 55–165 million years ago [8]. Similarly, minimal evolution over geological time scales has been demonstrated for deep subsurface archaeal lineages called Candidatus Altiarchaeota.

These critters use sulfate, like we use oxygen.