Climate change may allow the Earth’s oldest, tiniest creatures to dominate — and that's seriously bad news

The world's oceans are home to microscopic organisms invisible to the human eye. The tiny creatures, known as "prokaryotes", comprise 30% of life in the world's oceans.

These organisms play an important role in keeping the oceans in balance. But new research by myself and colleagues shows this balance is at risk.

We found prokaryotes are remarkably resilient to climate change — and as a result, could increasingly dominate marine environments.

This could reduce the availability of fish humans rely on for food, and hamper the ocean's ability to absorb carbon emissions.

A fine balance

Prokaryotes include both bacteria and "archaea", another type of single-celled organism.

These organisms are thought to be the oldest cell-based lifeforms on Earth. They thrive across the entire planet — on land and in water, from the tropics to the poles.

RELATED: Bizarre, never-before-seen viruses discovered thriving throughout the world's oceans