of 96 percent water, 3 percent protein, and 1 percent minerals. They have
no bones, hearts, or brains.
The umbrella of the crystal jellyfish does have an intriguing feature,
however. It is marked with hundreds of photoorgans that emit pinpricks of
green light. The organs only occasionally light up, and no one really knows
why the jellyfish decides to turn them on.
If Guinness World Records had an entry for the person who has
caught the most jellyfish in the world, Osamu Shimomura of Princeton
University in New Jersey and Woods Hole Oceanographic Institution
in Massachusetts would hold the title. He has caught more than one
million crystal jellyfish. That is how many it took for him to figure out
that all crystal jellyfish have two proteins involved in making light. One
is aequorin. Shimomura named this protein after
Aequorea victoria
, the
scientific name for the crystal jellyfish. The other is green fluorescent
protein, which sits right next to aequorin in the jellyfish’s photoorgans.
When the jellyfish releases calcium, it binds with the aequorin and releases
energy equivalent to blue light. The GFP then absorbs this energy and
emits it as a green fluorescent light that is visible to the human eye.
B i o f l u o r e s c e n c e • 4 3
