Glass Frogs Turn Translucent by Hiding Their Blood
Discovering how these frogs turn translucent could advance our understanding of human blood clotting, say researchers.
By Marisa Sloan
Jan 5, 2023 8:20 AM
(Credit: petrdd/Shutterstock)
We’ve all wished for the ability to disappear at one time or another. But for glass frogs, several species of tree frogs that call the tropical forests of Central and South America home, that dream is a reality … sort of. The bottle cap-sized body of the glass frog boasts a translucent belly and chest.
It’s a particularly helpful form of camouflage because it prevents predators from spotting the frog’s otherwise recognizable silhouette. Now new research, published in Science in December, reveals how the amphibians accomplish this trick: They shunt nearly all of their red blood cells straight to the liver.
Clear as Day
Many aquatic species, including certain jellyfish and crustaceans, have transparency on their evolutionary bingo cards, too — though it’s a bit easier for these sea-dwelling invertebrates. For one thing, light reflects differently when it's in air versus in water.
But for glass frogs and other invertebrates, the greatest challenge to translucency is their red blood cells, which naturally absorb light. Until recently, in fact, precisely how glass frogs wove their "invisibility cloaks" remained a mystery to scientists.
In the latest study, the authors focused exclusively on Fleishmann’s glass frog, or Hyalinobatrachium fleischmanni. These nocturnal amphibians are opaque at night, while actively eating and breeding. During the day, however, when they cling to the bottoms of tree leaves to catch some z’s, their bodies turn nearly transparent.
More:
https://www.discovermagazine.com/planet-earth/glass-frogs-turn-translucent-by-hiding-their-blood
Glass frog
