Explorer Moment of the Week: Secret Light

Picture of David Gruber studying corals
Photograph by Jim Hellemn


While exploring the Bloody Bay Wall off Little Cayman Island in 2012 to chronicle its biofluorescent creatures, marine biologist David Gruber felt the strange sensation of stepping into his backyard and beholding an unknown and surprising universe.


"Just a few hours after this photo was taken, darkness fell and I descended down the sheer face of the coral wall, along with teammates Jim Hellemn and John Sparks. The wall drops 1,000 feet, but we hovered at just 90, capturing the large biofluorescent mural that now appears in the traveling exhibit ‘Creatures of Light.’ On that evening, we unwittingly photographed many cryptic biofluorescent animals whose secret light had never before been glimpsed by human eyes.


Fluorescent proteins from marine species have already provided science with one of its most valuable tools for illuminating processes in living cells and neurons. So when it was announced that President Obama’s administration is planning to launch a decade-long initiative to map the human brain, I was inspired by new possibilities. Just as biofluorescence plays many roles for corals and fishes in their dim, blue-lit world, it may also come to play a greater role in understanding how our own brain cells communicate.


For example, as a thought pops into my head, my neurons fire (a process illuminated to science by biofluorescent tags decoded from the DNA of marine organisms). I imagine a role reversal: a pair of Warteye stargazers (Gillellus uranidea) exploring Greenwich Village with special lights and cameras, trying to discover how we communicate so as to better understand themselves. This planet is full of unsuspected biological connections and we are just beginning to explore the bioluminescent and biofluorescent universe under the sea.”


—David Gruber, National Geographic Society/Waitt Grantee


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