A place on Earth with no life?
| Date :26-Nov-2019 |
“ It would be impossible to imagine a spot on Earth where there is an absence of life, but European researchers have confirmed the non-attendance of microbial life in hot, saline, hyperacid ponds in the Dallol geothermal field in Ethiopia.”
WASHINGTON :
EARTH is known as the only habitable planet in the universe but a recent discovery about a place with no life on the planet might come as shock! It would be impossible to imagine a spot on Earth where there is an absence of life, but 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. It is one of the most torrid environments on Earth.
There, daily temperatures in winter can exceed 45° C and there are abundant hypersaline and hyperacid pools, with pH values that are even negative. A recent study which was published earlier this year, pointed out that certain microorganisms can develop in this multi-extreme environment (simultaneously very hot, saline and acid), which has led its authors to present this place as an example of the limits that life can support, and even to propose it as a terrestrial analogue of early Mars. 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. This is confirmed by the results of all the various methods used by the team, including the massive sequencing of genetic markers to detect and classify microorganisms, chemical analysis of brines and scanning electron microscopy combined with X-ray spectroscopy.