Photos: UV Light Reveals Surprising Hidden Message on the Beaks of Atlantic Puffins

While studying a bird called a twite, ornithologist Jamie Dunning got sidetracked and discovered something incredible in puffin beaks.

"Originally it was a bit of a mess around," Dunning told Newsweek. He was casually putting some specimens of his under black light with no particular expectations while procrastinating on another project. He found that, under black light, the beak and the area around the beak of the puffin specimen appeared to fluoresce brightly.

He tried this with other dead birds in his freezer, too. "I'm the kind of guy that people send dead birds to," Dunning explained. "We saw a little bit of fluorescent red in the goldcrest and the firecrest," Dunning explained, "but to be honest it's barely detectable, and nothing like the Atlantic puffin."

This discovery was of particular interest to Dunning, who studies phylogeny (evolutionary history) at the University of Nottingham. He knows from his studies that crested auklets fluoresce under blacklight, so he knew there was a potential that other birds would fluoresce as well.

Dunning suspects that the fluorescent markings on the puffin are present as some sort of signaling, or communication to other puffins. Unlike humans, the birds can see the secret signal in daylight because of their exceptional vision.

"They can see colors that we can't conceive and that's super important, actually," Dunning said. Different animals can see different colors because of small internal receptors called rods and cones. Humans have three cones that help us see the colors on the color wheel, but birds have four cones. That structural difference means that birds can see colors that we cannot. "We can't comment on what it looks like to a bird, it just looks different."

Dunning says that the fluorescence in the Atlantic puffin could have evolved for the purpose of sexual display to attract a mate, or possibly to help chicks see their parents. He's considering publishing a short paper on his observations, and hopes that this discovery will lead to more research into bird fluorescence.