Coral reefs are the most diverse marine ecosystem. These reef systems, made of animals called coral polyps, provide homes for a variety of marine life from octopuses to seahorses.
If you look more closely, corals house microscopic organisms such as Zooxanthellae which are algae that live within coral polyps and are responsible for the coral's fluorescing characteristics.
How Corals And Zooxanthellae Interact?
Coral and zooxanthellae share a mutual relationship. This means that both organisms benefit from one another.
Just like humans, coral polyps utilize cellular respiration to produce energy. Zooxanthellae cells, however, are like trees in that they utilize photosynthesis to produce energy. In order to perform these processes, each organism requires a resource produced by the other such as oxygen and carbon dioxide.
It has been found that as part of this mutualistic relationship, coral species living in shallow waters produce a bright fluorescence to shield the zooxanthellae from the harmful effects of the sun. However, until recently, it was unknown why coral thriving in deeper waters, where sun rays are not a threat, glow with the same bright fluorescence.
Why Do They Glow?
A study in Proceedings of the Royal Society B suggested that deepwater corals glow with an orange-red aura in order to simulate sun rays to sustain the zooxanthellae. Orange-red light most efficiently stimulates photosynthesis.
However, in deep waters, the ocean absorbs light within this color spectrum, depriving the zooxanthellae of an important resource. Researchers concluded that deepwater corals produce a fluorescent protein that can absorb blue light and in its place, generate an orange-red light. This light is able to penetrate through the coral tissues where the zooxanthellae live.
Fluorescence as A Solution?
In the medical field, scientists isolate proteins-- similar to the ones in deep water corals, to track cell behavior. By making cells fluoresce and taking images, they can better understand the behavior of cancerous cells as well as various diseases like Alzheimer's.
Employing a different protein, such as the one produced by deep water coral, would expand the possibilities of biomedical research.
Unfortunately, climate change is causing corals to bleach (lose color). Scientists are running out of time and are concerned that they may not be able to harvest the protein from deep water corals in time. Global warming is not only affecting the biodiversity but also threatening the future of medical advancement.
