Red Sea brine pools host unique microorganisms in extreme conditions

Scientists studying the Red Sea have discovered that hypersaline brine pools on the ocean floor, previously thought to be dead zones, host specialized microorganisms thriving in total darkness without oxygen.

Research conducted by the University of Miami and OceanX between 2020 and 2023 focused on sites such as the active NEOM brine pool in the Gulf of Aqaba, located at a depth of 1,770 meters, and the Hume Deep. In the NEOM pool, researchers identified bacteria and archaea that do not merely survive but actively influence the chemical composition of sediments. These organisms oxidize metals like manganese and iron to produce energy, resulting in significant enrichments of manganese and iron in the surrounding area.

At the Hume Deep, researchers found evidence of a former brine pool that has since disappeared. By dating echinoid skeletal remains, scientists estimated the pool's activity occurred between approximately 1,990 and 16,170 years ago. These findings suggest that such pools can form and vanish over millennia, leaving chemical traces in the sediment. These extreme environments serve as natural laboratories for studying how life might have persisted on early Earth when oxygen was scarce.