Climate change might allow Earth’s oldest and tiniest organisms to thrive, and that could spell trouble. Prokaryotes, microscopic creatures that have existed for billions of years, make up 30% of life in the world’s oceans. These resilient organisms play a crucial role in maintaining oceanic balance, but new research suggests that as the climate warms, prokaryotes could increasingly dominate marine environments.
This shift could disrupt the ocean’s ability to support fish populations and absorb carbon emissions, threatening food supplies and exacerbating global warming. As Earth’s oceans warm by 1°C to 3°C by the end of this century, the rise in prokaryote activity might significantly reduce the oceans’ capacity to mitigate climate change, making it harder to achieve global net-zero emissions.
Our study highlights the urgent need to better understand prokaryotes and their role in a changing climate, as their increased dominance could lead to unforeseen impacts on marine ecosystems and global food security.