What can survive
Living organisms tend to be sensitive to drastic changes in their environments. The cells that make them up can be seriously compromised in extreme physical (relating to temperature, desiccation, radiation, and pressure) and (geo)chemical (such as salinity, pH or heavy metals) conditions.
So what could survive in the Danakil’s harsh environment?
After a detailed study of the area, we have determined that there’s DNA evidence of microbial life. Life that, because of the similar extreme salty environment with volcanic origin, could be what’s surviving on Mars.
The microorganisms able to survive such extreme conditions must be a group of prokaryotes. All living things consist of two cell types: prokaryotes and eukaryotes. Organisms whose cells lack a nucleus and have DNA floating loosely in the liquid centre of the cell are prokaryotes. These are the most common and most ancient forms of life on earth.
What these microorganisms need is liquid water, metabolically suitable carbon, energy, and nutrient sources.