Colorful Glowing Corals Found

Scientists have discovered deep-sea corals that glow in lots of

colors—likely because it helps their algae friends.

Published September 29, 2015

Deep beneath the Red Sea’s surface, scientists were shocked to see corals lighting up the water with bright shades of orange and green. Although they already knew glowing corals existed in shallow waters, scientists hadn't studied these deeper dwelling creatures much—until now.

"I was indeed surprised to find such a great color diversity," says marine biologist Jörg Wiedenmann, whose team discovered the surprising corals at depths between 100 and 330 feet (30 to 100 meters). Wanting to learn more, Wiedenmann collected samples and took them back to his lab at the University of Southampton in England for a closer look.

Glowing corals closer to the water’s surface are more exposed to the sun. Their glow comes from light-producing pigments that act as sunblock. This helps protect them from the sun's rays, which can damage the corals and the algae that live inside them.

But back at his lab, Wiedenmann figured out that the pigments of the deep-sea corals weren't working as a sunscreen. Instead he thinks the pigments probably help create more light for the algae that live in the corals. Those algae need the light for photosynthesis, or the process of turning light into food for themselves.

The corals' range of colors could help more than just algae, though—they may someday play a role in improving human health. Wiedenmann says these pigments could help physicians to better see cancer cells in the body. It sounds like these corals have a bright future ahead.

Text from "Rainbow of Fluorescent Corals Found—Why Do They Glow?” by Carrie Arnold for National Geographic News

Adapted by Rose Davidson, NGS Staff