If you look closely at the animated image at right, you can see the gentle undulation of this molecule as its ribbons weave to and fro like the tentacles of the jellyfish from which it comes. Most proteins are actually quite dynamic in nature and continually flex and stretch in solution. This particular molecule, called green fluorescent protein, has the unusual property that it glows pale green in the dark; a feature appreciated by any swimmer who has seen a jellyfish at night.