You probably learned the frog lifecycle at school – here are some facts your teacher won’t have mentioned
1. Amphibians have existed for around 395 million years, and frogs first hopped onto the scene around 190 million years ago.
2. Frogs don’t drink through their mouths; they absorb the water they need through their permeable skin. Many have an extra thin patch on their underside known as a drinking patch.
3. You won’t see many frogs in winter
Frogs can escape the cold of winter by hibernating underwater or burrowing into the soil. While they sleep, a new layer of growth forms on their bones, creating age rings similar to the ones found in trees. Some species, like the wood frogs, hide among leaf litter and let their bodies freeze. Their hearts stop beating, their blood stops flowing and up to 65 per cent of the water in their body freezes, but come spring they thaw and hop off.
4. Toads are frogs. They all belong to the order Anura – toads are just frogs with short legs and dry, bumpy skin.
5. The world’s largest frog is the Goliath frog. It can grow to 32 centimetres (12.6 inches) in length and weigh as much as a newborn baby.
6. Many frogs can use their strong legs to cover more than 20 times their own body length in a single jump.
7. Frogs swallow with their eyes
With their round, bulging eyes, frogs can see in almost every direction at once. They also have an extra eyelid. Known as a nictitating membrane, it is semitransparent and both lubricates the eye and protects it underwater. When a frog is swallowing a particularly large piece of food it will blink hard, forcing its eyes back into its head to help push the food down.
8. The Bornean flat- headed frog is the first frog discovered to have no lungs. Rather than breathing, it takes in all the oxygen it needs through its skin.
9. Not all frogs hop – some walk and run, and waxy tree frogs grip branches with opposable toes and move like chameleons.
10. Some tropical frogs are absolutely lethal
Poison dart frogs are the most poisonous vertebrates in the world. Their name comes from the use of their poison by South American hunters to lace the tips of blow darts. The toxin secreted from the skin of the 5.5-centimetre (2.2-inch) golden poison dart frog is strong enough to kill ten men.
For more fun frog facts, make sure you pick up your copy of World of Animals Issue 64!