Scientists have accidentally discovered glowing amphibians in South America, just in time for everyone to get a dose of green this St. Patrick’s Day.
The discovery of the first naturally occurring fluorescent frog in Argentina was made while scientists from that country partnered with colleagues in Brazil to study the metabolic origin of pigments in a tree-frog species.
The frog’s skin is translucent under normal light, a muted yellowish-brown colour with red dots.
But shine a UV light on the frog and it turns a fluorescent celestial green.
The scientists told AFP that this was “the first scientific record of a fluorescent frog.”
“We were very excited,” said his fellow researcher Julian Faivovich. “It was quite disconcerting.”
He said the discovery
“radically modifies what is known about fluorescence in terrestrial environments, allowing the discovery of new fluorescent compounds that may have scientific or technological applications.”
It also “generates new questions about visual communication in amphibians,” he said.
The team studied some 200 more examples to ensure the phenomenon was not due to the frog’s captivity, and detected the fluorescent properties in all the specimens.
Maria Lagorio — an independent researcher and expert in fluorescence, who the research team contacted after the discovery — told AFP that the trait is common in aquatic species and seen in some insects, “but has never been scientifically reported in amphibians.”
The finding was recently published in Proceedings of the National Academy of Sciences.
In this interdisciplinary study, we report naturally occurring fluorescence in amphibians; specifically, in a common South American tree frog. We show that fluorescence is traceable to a class of compound that occurs in lymph and skin glands. Our study indicates that in our model species, in low-light conditions, fluorescence accounts for an important fraction of the total emerging light, largely enhancing brightness of the individuals and matching the sensitivity of night vision in amphibians. These findings open an exciting perspective into frog visual physiology and ecology and into the role of fluorescence in terrestrial environments, where classically it has been considered irrelevant.