Phospholipid fatty acids in the Atacama Desert soils can help identify living microbes. The study showed that microbial abundance and diversity increased from the north to the south of the desert. Microbes in the Atacama are adapted to harsh conditions like low nutrients and high salt levels. Different levels of rainfall affected microbial biomass and diversity. Certain types of fatty acids were linked to microbial viability, soil properties, and organic content. The degradation of fatty acids decreased with very low rainfall. These findings could help identify potential biomarkers for life on Mars with similar membrane structures.