A spot on Earth with no life discovered
New Delhi : It becomes impossible to imagine Earth with no life on it; but a recent discovery has shocked everyone with a place on the planet that has no life.
European researchers have confirmed the non-attendance of microbial life in hot, saline, hyperacid ponds in the Dallol geothermal field in Ethiopia.
The infernal landscape of Dallol, located in the Ethiopian depression of Danakil, extends over a volcanic crater full of salt, where toxic gases emanate and water boils in the midst of intense hydrothermal activity.
In Dallol, the daily temperature can go as high as 45 degrees in the winters with presence of abundant hypersaline and hyperacid pools, with pH values that are even negative.
Recently, a study was published claiming that microorganism can develop on earth even in extreme conditions, but the authors now have this place as an example to show limits that life can support.
But these fresh findings present a contrary fact and were published in the journal Nature Ecology and Evolution.
“After analysing many more samples than in previous works, with adequate controls so as not to contaminate them and a well-calibrated methodology, we have verified that there’s no microbial life in these salty, hot and hyperacid pools or in the adjacent magnesium-rich brine lakes,” stressed biologist Lopez Garcia, French National Centre for Scientific Research.
“What does exist is a great diversity of halophilic archaea (a type of primitive salt-loving microorganisms) in the desert and the saline canyons around the hydrothermal site,” the biologist explained.
Garcia alerted that some silica-rich Dallol mineral precipitates may look like microbial cells under a microscope, so what is seen must be analysed well: “In other studies, apart from the possible contamination of samples with archaea from adjacent lands, these mineral particles may have been interpreted as fossilized cells, when in reality they form spontaneously in the brines even though there is no life.”
According to the authors, this work “helps to circumscribe the limits of habitability and demands caution when interpreting morphological bio-signatures on Earth and beyond,” that is, one should not rely on the apparently cellular or ‘biological’ aspect of a structure, because it could have an abiotic origin.
“In addition, our study presents evidence that there are places on the Earth’s surface, such as the Dallol pools, which are sterile even though they contain liquid water,” said Garcia.
This means that the presence of liquid water on a planet, which is often used as a habitability criterion, does not directly imply that it has life.