Glass act: Scientists reveal secrets of frog transparency


              This photo provided by researchers in December 2022 shows a sleeping glass frog photographed with a flash from its back side, showing its leaf-green coloration in reflected light. Some frogs found in South and Central America have the rare ability to turn on and off their nearly transparent appearance, researchers report Thursday, Dec. 22, 2022, in the journal Science. (Jesse Delia/AMNH via AP)
            
              This photo provided by researchers in December 2022 shows a female glass frog with eggs in her transparent ovaries, photographed from below using a flash. Some frogs found in South and Central America have the rare ability to turn on and off their nearly transparent appearance, researchers report Thursday, Dec. 22, 2022, in the journal Science. (Jesse Delia/AMNH via AP)
            
              This photo provided by researchers in December 2022 shows glass frogs, strict leaf dwelling frogs, that sleep, forage, fight, mate, and provide (male) parental care on leaves over tropical streams. Some frogs found in South and Central America have the rare ability to turn on and off their nearly transparent appearance, researchers report Thursday, Dec. 22, 2022, in the journal Science. (Jesse Delia/AMNH via AP)
            
              This photo provided by researchers in December 2022 shows a glass frog, strict leaf dwelling frogs, that sleep, forage, fight, mate, and provide (male) parental care on leaves over tropical streams. Some frogs found in South and Central America have the rare ability to turn on and off their nearly transparent appearance, researchers report Thursday, Dec. 22, 2022, in the journal Science. (Jesse Delia/AMNH via AP)
            
              This photo provided by researchers in December 2022 shows a group of glass frogs sleeping together upside down on a leaf, showing their leaf camouflage in transmitted (downwelling) light. Some frogs found in South and Central America have the rare ability to turn on and off their nearly transparent appearance, researchers report Thursday, Dec. 22, 2022, in the journal Science. (Jesse Delia/AMNH via AP)
            
              This photo provided by researchers in December 2022 shows a male glass frog photographed from below using a flash, showing its transparency. Scientists measured muscle and ventral skin, finding that these tissues transmit over 90% of visible light and are yet perfectly functional. Some frogs found in South and Central America have the rare ability to turn on and off their nearly transparent appearance, researchers report Thursday, Dec. 22, 2022, in the journal Science. (Jesse Delia/AMNH via AP)
            
              This combination of photos provided by researchers in December 2022 shows the same glass frog photographed during sleep, under anesthesia, and while active (in transmitted light), showing the difference in red blood cells within the circulatory system. Some frogs found in South and Central America have the rare ability to turn on and off their nearly transparent appearance, researchers report Thursday, Dec. 22, 2022, in the journal Science. (Jesse Delia/AMNH via AP)
            
              This photo provided by researchers in December 2022 shows a glass frog, strict leaf dwelling frogs, that sleep, forage, fight, mate, and provide (male) parental care on leaves over tropical streams. Some frogs found in South and Central America have the rare ability to turn on and off their nearly transparent appearance, researchers report Thursday, Dec. 22, 2022, in the journal Science. (Jesse Delia/AMNH via AP)
Glass act: Scientists reveal secrets of frog transparency