He placed them in a Petri dish and saw each frog's circulatory system through its translucent skin — "red with red blood cells." But when he came back later, the frogs were sleeping and the ...

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 ...

Wake the frog up, and cells just unpack themselves ... “It was really obvious that I couldn’t see any red blood in the circulatory system,” Delia says. “I shot a video of it — it was ...

But West Africa’s critically endangered Nimba toad (Nimbaphrynoides occidentalis) is the only frog fed entirely ... interlacing their own circulatory system with that of their developing young ...

Kambô comes from the giant monkey tree frog (Phyllomedusa bicolor ... system—essentially the body's drainage system, running parallel to the blood circulatory system—and thence into the ...