Antarctica has its very own microbes

Antarctica appears to harbour a unique, hitherto largely hidden world beneath the soil. Researchers have identified strains of bacteria that have not yet been found anywhere else on Earth. The discovery shows that the continent’s geographical isolation can act as a significant barrier even for microorganisms.

A research team led by the Cooperative Institute for Research in Environmental Sciences (CIRES) at the University of Colorado Boulder investigated bacteria from the Arthrobacter group. These microorganisms are found in soils worldwide and can survive even under extreme conditions.

The researchers analysed more than 100 Antarctic bacterial strains and compared their genomes with nearly 500 strains from other regions, including Svalbard, the Tibetan Plateau and the Atacama Desert.

The surprising result: around 90 per cent of the Antarctic strains studied had not previously been detected anywhere outside Antarctica. This suggests that at least some of the continent’s microorganisms have evolved largely independently over a long period of time.

Specialists in extreme conditions

Laboratory experiments also showed that Antarctic bacteria grow relatively slowly but are particularly resistant to cold and dry conditions. They have evidently adapted specifically to the extreme environmental conditions of Antarctica.

The findings thus also challenge the long-held notion that microorganisms, due to their minuscule size, could spread practically anywhere on Earth.

The discovery also suggests that a significant proportion of Antarctic biodiversity may be hidden from view in the soil. The researchers now intend to investigate whether other groups of microorganisms also have a similarly high proportion of endemic species.

The study, ‘Evidence for endemism and local adaptation in Antarctic soil bacteria’, was published on 31 August 2026 in the Proceedings of the National Academy of Sciences (PNAS).

Heiner Kubny, PolarJournal