Glass Frogs

Imagine a tiny tree frog that looks like a little piece of lime-green candy. Now, flip that frog over. Its belly isn't white or green—it is completely see-through, just like a window!

Because their skin is translucent (which means clear enough for light to pass through), you can look right through their bellies. If you look closely at a glass frog from underneath, you can actually watch its tiny heart beating, see its white bones, and spot its dinner moving through its tummy!

Here are a few awesome facts about these real-life cartoon characters:

• They are super tiny: Most glass frogs are only about the size of a single marshmallow or a large paperclip.
• Invisible Cloak: From the top, they are bright green with little yellow spots. When they sit on a leaf, they blend in perfectly. The see-through edges of their bodies soften their shadows, making them look exactly like a part of the leaf so hungry birds can't find them.
• Super Dads: Glass frog fathers are total heroes. After the mom lays eggs on a leaf hanging over a stream, the dad stays behind to guard them from wasps and spiders. He will even kick predatory bugs right off the leaf to keep his babies safe!
• Built-in Camouflage: When they go to sleep, they actually hide the red blood cells inside their liver so their bodies become even more see-through. Talk about a neat magic trick!