It’s tough being a frog. You have to account for opposing lanes of traffic across a busy highway and, if you get through that, you have to hop across logs and the backs of turtles, avoiding alligators ...

Glass frog photographed during sleep and while active, showing the differences in red blood cells within the circulatory system. Jesse Delia via AMNH When a tiny glass frog dozes off to sleep, its ...

What if you had the power of invisibility, but it only works when you’re asleep? That might be useful for a surreptitious nap in public, but it still probably wouldn’t suit you as well as it does the ...

Now you see them, now you don't. Some frogs found in South and Central America have the rare ability to turn on and off their nearly transparent appearance, researchers report Thursday in the journal ...