🦠 A large number of unknown microbes are developing around Antarctica

The Southern Ocean, which surrounds Antarctica, hosts a myriad of microscopic organisms that actively participate in regulating the Earth's climate by absorbing immense amounts of heat and carbon dioxide.

An international team of scientists, led by biogeochemist Nicolas Cassar, has undertaken a vast genetic study to unravel the workings of this microbial world. Their work, published in Nature Communications, is based on nearly ten years of research and samples collected during a three-month expedition in the Southern Ocean. The objective was to map the DNA of these microorganisms to understand their diversity and functioning.


Genetic analyses revealed that more than one-third of the identified genes are not listed in existing catalogs. This discovery shows how limited the knowledge of marine microbes still is. The researchers sequenced DNA from water samples and compared the results with databases, highlighting a genetic diversity that was previously unknown. Biogeochemist Nicolas Cassar indicates that this significant portion of genes absent from databases signals largely unknown territories.

The distribution of these microbial communities is not uniform across the Southern Ocean. They form distinct ecosystems, influenced by ocean currents. Some thrive in cold surface waters, while others are present at greater depths. This spatial organization shows the adaptation of microorganisms to their environment and highlights the interactions between marine life and the physical conditions of the ocean.

Understanding these mechanisms is important for anticipating climate evolution. Microbes regulate a large part of ocean chemistry, and their genes control important processes such as carbon absorption. Thus, this study paves the way for better modeling of the role of the Southern Ocean in the global climate system. Scientists seek to establish links between genetic diversity and ecological functions to predict responses to environmental changes.

The next steps of the research aim to explore this newly discovered genetic diversity in more detail. By linking genes to ecological functions, researchers hope to clarify how these microbes influence and respond to climate change.