Science News: A fluorescent protein found in a Japanese eel glows green in the presence of bilirubin, a pigment that can indicate jaundice or liver problems in humans. The discovery was made by Atsushi Miyawaki and his coworkers of the RIKEN research institute in Japan while they were studying the species Anguilla japonica to find out why the eels glow green. What they found was that a protein called UnaG, located in the eels’ muscle fibers, glows when it comes in contact with bilirubin. Although the researchers are not entirely sure why UnaG does that, they have used a lab-made version of the protein to develop a simple blood test to check for elevated levels of the protein in humans.