It’s easy to forget that corals are animals, mostly because they don’t move. But they’re also pretty hard to study while they are alive. Until recently, attempts to image coral faltered because the opaque coral tissue is composed of multiple cell layers. Furthermore, visible light can stimulate photosynthesis and UV light can harm corals.
An international team of researchers has developed a new method to image living corals though, and it could have a huge impact on how we study the creatures. They used optical coherence tomography (OCT), which uses near-infrared radiation to penetrate deeper into tissue and reveals microscopic structures with different reflective properties. It works somewhat like ultrasound, and up until now was used primarily to study the human eye and monitor tissue damage there.
What the researchers have been able to do so far has taught us a lot about coral, and there is the potential to learn a great deal more. Corals are complex creatures that form the basis of coral reefs, which are of significant ecological importance. Coral reefs are home to a huge diversity of species, and each one is essentially unique, even when it shares traits with other coral reefs. But they are also incredibly fragile ecosystems, susceptible to global climate change, ocean acidification, pollution, overfishing, and other perils. One growing problem, bleaching, is dealing significant damage to reefs around the world, and isn’t likely to go away without some major changes on our part.
But with the discovery that OCT technology can be used to image and study corals, researchers might be able to do something more about that problem, and many others. As scientists learn more about corals, like how they react to stress, they can develop better systems to protect them, and figure out exactly what steps are needed in order to prevent further damage to coral reefs.
“OCT is a powerful technique for studying the dynamic structure of living corals and their behavioral response to environmental stress,” said research leader Professor Michael Kühl at the University of Copenhagen. “It now enables many novel applications in coral science as well as in other areas of marine biology. Our study also illustrates the importance of interdisciplinary approaches in science. Who would have thought that a technique used in the eye clinic would be useful for coral research?”