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SCIENCE

of early Mars. “After analyzing many “And all this despite the fact that mi- tive salt-loving microorganisms) in the
more samples than in previous works, crobial dispersion in this area, due to desert and the saline canyons around
with adequate controls so as not to con- the wind and to human visitors, is in- the hydrothermal site,” the biologist
taminate them and a well-calibrated tense,” Lopez Garcia said. said, “but neither in the hyperacid and
methodology, we have verified that The hot, salty, hyperacid pools con- hypersaline pools themselves, nor in
there’s no microbial life in these salty, tain no microbial life at all, according the so-called Black and Yellow lakes
hot and hyper acid pools or in the adja- to a French-Spanish team of research- of Dallol, where magnesium abounds.
cent magnesium-rich brine lakes,” said ers who published an article in Nature And all this despite the fact that micro-
study co-author Purificacion Lopez Ecology and Evolution. bial dispersion in this area, due to the
Garcia from FECYT. Dallol extends over a volcanic crater wind and to human visitors, is intense.”
The researchers found great diver- full of salt, where toxic gases are emit- “Our study presents evidence that
sity of a type of primitive salt-loving ted and water boils amid intense hy- there are places on the Earth’s surface,
microorganisms in the desert, and the drothermal activity, the Spanish Foun- such as the Dallol pools, which are ster-
saline canyons around the hydro ther- dation for Science and Technology said ile even though they contain liquid wa-
mal site but not in the hyper acid and in a statement. Daily temperatures in ter,” she said.
hyper saline pools, nor in the Black and winter can exceed 113 degrees, and the
Yellow lakes of Dallol which are rich in pools can be so acidic they have a nega- rior studies said that specific mi-
magnesium. tive pH value. croorganisms can form in this
P multi-extraordinary environ-
ment condition and scientists intro-
Dallol’s landscape
A SALT VOLCANO extends over a volcanic duced the spot as an instance of limits
of conditions that are able to bolster
even proposed as an earthly analogue
Dallol looks like a salt vol- crater full of salt, life. The scientists said the spot was
cano with intense degassing and of early Mars.
hydrothermal activity on top. constantly releasing The scientists found an assorted
Lying on the Danakil depression toxic gases with water variety of salt loving microorganisms
along the East African Rift, the in the desert, and the saline gulches
whole region undergoes intense boiling in the midst around the hydrothermal site however
tectonic, seismic and volcanic of the intense hydro not in the hyperacid and hypersaline
activity, being one of the hottest pools, nor at rich in magnesium black
places on Earth (daily winter thermal activity, and Yellow pools of Dallol.
temperatures can easily exceed The specialists affirmed the discov-
45°C!). Dallol and its surround- reseachers have eries with a few different techniques
ings display unique combinations pointed out including an enormous scale sequenc-
of physicochemical parameters, ing of genetic markers to recognize and
from hypersaline sites (cave classify microorganisms, microbial
reservoirs in the Dallol west salt The new study contradicts another culture endeavors, utilizing fluorescent
canyons, southern Lake Assale), study published earlier this year that probes to distinguish singular cells,
to the acidic hypersaline mag- suggested there was some life in the substance investigation of the hypersa-
nesium-rich brines (Black and dead zones. But researchers in the new line waters.
Yellow lakes south to the dome) study said their methods were better. They likewise utilized scanning elec-
and the hypersaline, hyperacidic “After analysing many more samples tron microscopy and X-ray spectrosco-
(down to negative pH!) and hot than in previous works, with adequate py to get into the water samples looking
pools on Dallol’s dome. Although controls so as not to contaminate them for signs of life. As per researchers, the
halophilic, acidophilic and hyper- and a well-calibrated methodology, we study helps in understanding the limits
thermophilic microorganisms are have verified that there’s no microbial of habitability and also helps in pre-
well known, do microorganisms life in these salty, hot and hyperacid senting evidence that there are places
exist that are adapted simultane- pools or in the adjacent magnesium- on the surface of the Earth that are ster-
ously to several of those extreme rich brine lakes,” biologist Purificación ile, even though they contain liquid wa-
conditions? This is the million- Lopez Garcia of the French National ter. They also mentioned that the pres-
dollar question, answer for which Centre for Scientific Research said in ence of liquid water on a planet does
scientists are looking for. the statement. not directly imply the presence of life.
“What does exist is a great diversity
of halophilic archaea (a type of primi- LETTERS@TEHELKA.COM

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