The existence of water does not always mean that life can occur. It is the researchers’ conclusion after in vain looking for signs of life in Africa’s most inhospitable place.
Even the coldest, hottest and driest areas of the earth can show some form of life. However, now a team of French and Spanish researchers has determined that there is a place that completely lacks all forms of biological life. The group has studied the geothermal sources surrounding the Dallol volcano in Ethiopia, where several of the springs are spraying brine and acidic liquids.
The area is 60 kilometers north of the capital Addis Ababa. Earlier this year, other researchers published a study claiming that microorganisms can survive in the diverse hostile environment – in a model that was said to be representative of the early conditions on Mars. But the negative pH and toxic gases together with high temperatures have proved to be too much.
After analyzing many more samples than in the previous work – with adequate supervision so that we do not contaminate them, and a well-calibrated methodology – we have verified that there is no microbial life in these salty, hot and super-acid pools, or in the adjacent magnesium-rich salt lakes, says the research leader Purificación López García to Phys Org.
While the surrounding Danakil desert, with its salty valleys, is riddled with the primitive microorganism halophilic archaea – the basins are completely empty. To test this, the researchers have used DNA sequencing, bacterial culture experiments and chemical analysis.
Their study has also shown that some siliceous minerals under a microscope can look almost identical to the cells of microorganisms. An interesting conclusion, from the perspective of exploring new worlds, is that the existence of water does not necessarily mean that life can arise. The researchers’ work is published in Nature Ecology & Evolution.