Researchers at the University of Colorado Boulder have discovered that 90 percent of specific Antarctic soil microbes are endemic to the continent and found nowhere else on Earth. Published on August 31, 2026, the findings challenge the long-standing microbiological assumption that microscopic life is universally distributed across the globe.
Challenging the ‘Everything Is Everywhere’ Rule in Microbiology
For decades, microbiology operated under a guiding assumption that microbial life travels effortlessly across the globe, carried by atmospheric winds and oceanic currents. Under this framework, microscopic organisms should lack the geographic boundaries that define plants and animals. But a new investigation led by investigators at the Cooperative Institute for Research in Environmental Sciences (CIRES) at CU Boulder turns that conventional wisdom on its head.
Nick Dragone and Center for Microbial Exploration Director Noah Fierer set out to test whether Earth’s southernmost continent serves as an exception to the rule. Their peer-reviewed findings, published in the Proceedings of the National Academy of Sciences (PNAS), demonstrate that certain soil microbes residing in Antarctica do not exist anywhere else on the planet.
“There is a long-standing assumption in microbiology that ‘everything is everywhere,’ Antarctica has often been viewed as a possible exception, and our findings support that idea. Some Antarctic soil microbes appear to be distinct from those found in soils elsewhere around the world.”
Nick Dragone, at CU Boulder, via Earthsky and earth.com
Sampling Cold Deserts and Sequencing Genomes
To conduct a fair cross-continental comparison without skewing results through rare organisms, the research team focused on Arthrobacter, a bacterial group common in soils from Colorado to the tropics and capable of thriving in a laboratory dish. Rather than sampling only the frozen continent, the scientists gathered soil from a suite of extreme, cold, and dry environments worldwide.
The team analyzed more than 100 Antarctic strains alongside nearly 500 strains collected from disparate locations, including the Tibetan Plateau, Svalbard in the Arctic, and Chile’s Atacama Desert. According to decades of sample collection by international research teams across Antarctica for unrelated projects, the physical groundwork for this study was already in place.
First, the researchers sequenced the genomes of the Antarctic Arthrobacter strains, cataloguing their genetic makeup in detail. When they lined those genetic profiles up against soil bacteria pulled from public databases worldwide, the genomic traits revealed a startling reality.
“Arthrobacter as a group may be found all over the planet, but when we look closely at individual strains, just like penguins, Antarctica clearly has its own distinctive biological history.”
Byron Adams, study co-author and biology professor at Brigham Young University, via Earthsky and earth.com
Laboratory Stress Tests Under Simulated Antarctic Conditions
After genomic sequencing revealed that 90 percent of the Antarctic strains matched nothing found elsewhere on Earth, the team moved the investigation into a laboratory setting at CU Boulder. Researchers simulated the extreme cold and dryness of the southern desert to watch how the bacteria coped under pressure.
The Antarctic strains grew slower than their global counterparts, yet they held up remarkably well under stress. They outlasted conditions that likely would have wiped out less hardened competitors, displaying adaptations tailored to their isolated home.
Noah Fierer noted that while scientists already knew that a broad diversity of microbes can survive the inhospitable conditions of Antarctica, the new data confirms that a significant portion of those microscopic residents are uniquely adapted to life on the southern continent.
“If we do find we’re looking for endemic microorganisms, a good place to start is Antarctica, because it’s an entire continent that is geographically isolated. It also has unique conditions not typically found in other soil environments. Cold is the obvious one, but also super dry; Antarctica is a desert.”
Noah Fierer, Center for Microbial Exploration Director at CU Boulder, via Earthsky and earth.com
Rethinking Polar Biodiversity and Conservation
Conservation discussions in the region typically focus on charismatic megafauna like penguins, seals, and whales. However, the discovery of widespread endemic microbial life suggests that Antarctica’s biological uniqueness extends to the microscopic level.
As Byron Adams observed, safeguarding the continent requires acknowledging the history hidden underneath the ice. Protecting Antarctic biodiversity means recognizing that a handful of soil contains a distinct biological history.
With endemic strains confirmed in Antarctica, researchers plan to investigate whether similar patterns exist in other isolated environments across the globe, opening a new chapter in microbial ecology.
