How Antarctica's Blood Falls came to be

Antarctica's Blood Falls, a striking red-orange stain on the icy landscape, likely dates back millions of years, despite its appearance of continuous bleeding. Despite the barren, seemingly lifeless surroundings, the waters harbor a diverse community of microscopic life, offering insights into the formation of this enigmatic feature.

Andrew Allen, a marine biologist at the Scripps Institution of Oceanography, describes the landscape as pristine, devoid of typical Arctic wildlife or vegetation, creating an almost abiotic environment. However, these waters harbor eukaryotic species, those with membrane-bound cells, which are not found in the underlying, iron-rich saltwater lake feeding Blood Falls.

Instead, these species are more closely related to ocean-dwelling organisms, while those from nearby sites are associated with fresh water. The presence of these marine microbes could be attributed to wind dispersal or remnants from an era when seawater was cut off from the ocean as the glacier advanced over the water at around two million years ago.

This isolated ecosystem of eukaryotic species has persisted since the time of Homo erectus, making further study crucial to understanding how microscopic life has survived through significant geological and climatic changes. One remaining mystery is the presence of abundant iron in the area, which typically supports phytoplankton.

Allen and his team are eager to investigate how these organisms utilize the iron present in Blood Falls.