Beneath the extremely dry surface of Chile’s Atacama Desert, scientists have discovered a functional community of microorganisms that challenges our view of life. While the ground above is one of the harshest environments on Earth, a ‘hidden oasis’ lies about two meters below, protected from high solar radiation and complete dryness. This underground community consists mainly of unique bacteria that obtain the moisture needed to survive from the minerals. The researchers used cutting-edge DNA sequencing and geochemical techniques to make the discovery. Their work shows that life can flourish even without being attached to the surface. This revelation not only changes our view of where life can exist on Earth, but also provides valuable insights for the search for similar forms of life on Mars or other barren planets.
Scientists discover secret underground life 2 meters beneath Chile’s Atacama Desert
As reported in the journal PNAS Nexus, a team of scientists in Yunga Canyon discovered a variety of microbes living two meters below the surface. This area is the driest part of the Atacama Desert. Surface organisms depend on rare rainfall, but these underground microorganisms do not depend on the atmosphere at all. The researchers used advanced molecular tools to show that these bacteria are not just dormant spores. Instead, they form a metabolically active and functioning ecosystem that thrives in constant darkness.
How gypsum holes sustain life for an oasis
The existence of this hidden oasis is made possible by the presence of vesicular gypsum. This mineral has tiny pores that trap bits of water, which serve as storage sites for microbes. Actinobacteria, which are highly tolerant taxa, make up the majority of this community, according to the journal PNAS Nexus. They learned how to harness mineral-rich moisture, allowing them to live in places once thought to be barren.
Why are scientists exploring beneath the surface of Mars?
This discovery gives us a clear example on Earth for exploring Mars. Mars has harsh conditions, with deadly radiation and cold temperatures, so scientists think any life there would likely exist beneath the surface, similar to what we see in the Atacama Oasis. The discovery of habitable places two meters below Earth’s most Mars-like region marks a paradigm shift. Future planetary missions should focus on subsurface sampling to search for signs of life beyond our planet.
Team used salt and water chemistry to detect ancient life
The research team took steps to rule out surface pollution as the cause of their findings. For this purpose he used both ‘genomics’ and ‘geochemistry’ methods. As reported in the journal PNAS Nexus, by examining salt levels and determining the age of water trapped in minerals, they concluded that these microbes had been present in the soil for geological time. Their presence was not influenced by current surface climate conditions.