Researchers from many countries have learned that every kind of coral carries its own special group of tiny living things called microbes. These microbes are invisible to the eye, but they make coral reefs even more diverse than we thought.
Why Coral Reefs Matter
Coral reefs are often called the rainforests of the sea. They hold about one‑third of all the animals we can see in the ocean. People also love them for tourism, and they help move nutrients through the water.
What most people miss is the hidden world of microbes that lives inside the coral. This microscopic community, known as the microbiome, is essential for the health of the reef.
Big Study Finds Thousands of New Microbes
With help from the Tara Pacific project, scientists took samples from 99 reefs on 32 Pacific islands. They rebuilt the DNA of 645 different microbes. More than 99 % of these microbes had never been described before.
Many of these microbes make special chemicals that could become medicines or tools for industry. The reef microbes also have the most diverse set of gene clusters for making natural compounds that any ocean area has ever shown.
What We Still Don’t Know
Dr. Maggie Reddy from the University of Galway says we only understand a tiny part of this hidden life. Out of more than 4,000 microbial species found, just 10 % have any genetic data, and less than 1 % have been studied at all. This shows a huge gap in our knowledge and the need for more surveys, especially in places that have been ignored.
Coral Reefs as a Chemical Library
When reefs are damaged, we lose not only fish and plants but also a massive “library” of chemicals made by the microbes. These chemicals could help create new medicines and biotech tools.
New Enzymes and Biotech Hope
Professor Olivier Thomas points out that the reef microbes can produce enzymes that rival those from famous natural sources like sponges. Some newly found bacteria, such as members of Acidobacteriota, create enzymes that could be useful in biotechnology.
The study is a clear call to protect reefs—not just for the colorful creatures we see, but also for the hidden chemistry that could shape future science.
Future Trips and Collaboration
The research team includes scientists from the Ryan Institute, ETH Zurich, and many other partners. They will join the upcoming Tara Coral expedition in Papua New Guinea to collect more samples and learn why some corals survive climate stress better than others.
Understanding the Coral Microbiome
The coral microbiome is made of bacteria, archaea, fungi, viruses, and tiny algae that live on or inside coral tissue. Together they form a system called the holobiont, which is vital for coral survival.
The samples were gathered during Tara Pacific trips from 2016 to 2018, creating one of the most detailed maps of coral microbiomes across a region that holds about 40 % of the world’s reefs.