Rare marine microbes key to ocean stability: IIT Madras study

A new study by IIT Madras researchers has found that rare 'specialist' marine bacteria are far more critical to the stability of ocean ecosystems than previously thought. The study, published in the journal mSystems, analysed sequencing data from over 4,600 ocean samples across tropical, temperate, and polar regions.

The researchers identified that these low-abundance specialist microbes act as vital connectors in microbial interaction networks. Their removal in computational models significantly weakened network stability, showing they play an outsized role in maintaining resilient marine environments. The work was led by Prof Karthik Raman, with postdoctoral researcher Aarti Ravindran and undergraduate student Pranathi Ravikumar.

The study also found that polar microbial communities had more modular interaction networks, while tropical and temperate communities were shaped by both environmental selection and random ecological processes. The team says understanding these dynamics can help conservation efforts and support the UN's goal for 'Life Below Water'.