14 Fun Facts About Frogs

#4: When Darwin’s frog tadpoles hatch, a male frog swallows the tadpoles

The Glass Frog
The Glass Frog (Centrolenella colymbiphyllum) has skin so translucent that you can watch its heart beating. Carl C. Hansen, Smithsonian Institution

When I started working on this frog blog post (inspired by the adorable yet deadly poison dart frogs at the National Zoo), my knowledge of frogs was limited to Mr. Toad from The Wind in the Willows and Kermit. Obviously, I had a lot to learn. I have since discovered many amazing, surprising, disgusting and flat-out weird facts about frogs, and have collected the 14 best to share here with you:

1 ) One gram of the toxin produced by the skin of the golden poison dart frog could kill 100,000 people.

2 ) The female Surinam toad lays up to 100 eggs, which are then distributed over her back. Her skin swells around the eggs until they become embedded in a honeycomb-like structure. After 12 to 20 weeks, fully formed young toads emerge by pushing out through the membrane covering the toad’s back.

3 ) A frog completely sheds its skin about once a week. After it pulls off the old, dead skin, the frog usually eats it.

4 ) When Darwin’s frog tadpoles hatch, a male frog swallows the tadpoles. He keeps the tiny amphibians in his vocal sac for about 60 days to allow them to grow. He then proceeds to cough up tiny, fully formed frogs.

5 ) When a frog swallows its prey, it blinks, which pushes its eyeballs down on top of the mouth to help push the food down its throat.

6 ) The wood frog of North America actually freezes in the winter and is reanimated in the spring. When temperatures fall, the wood frog’s body begins to shut down, and its breathing, heartbeat and muscle movements stop. The water in the frog’s cells freezes and is replaced with glucose and urea to keep cells from collapsing. When there’s a thaw, the frog’s warms up, its body functions resume and it hops off like nothing ever happened.

7 ) A group of birds is called a flock, a group of cattle is called a herd, but a group of frogs is called an army.

8 ) The glass frog has translucent skin, so you can see its internal organs, bones and muscles through its skin. You can even observe its heart beating and its stomach digesting food.

9 ) There is a frog in Indonesia that has no lungs – it breathes entirely through its skin.

10 ) The waxy monkey frog secretes a wax from its neck and uses its legs to rub that wax all over its body. The wax prevents the skin of the frog from drying out in sunlight.

11 ) Most frogs have teeth, although usually only on their upper jaw. The teeth are used to hold prey in place until the frog can swallow it.

12 )  The biggest frog in the world is the Goliath frog. It lives in West Africa and can measure more than a foot in length and weigh more than 7 pounds – as much as a newborn baby.

13 )  There’s a type of poison dart frog called the blue-jeans frog; it has a red body with blue legs. It is also sometimes called the strawberry dart frog.

14 )  The red-eyed tree frog lays it eggs on the underside of leaves that hang over water. When the eggs hatch, the tadpoles fall into the water below.

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