Amphibians

Get ready for “toad-al” fun with Bill Nye and the “Amphibians” episode.

Frogs, toads, salamanders, newts, and caecilians (worm-like animals that have backbones) are all amphibians, animals that spend part of their lives in water and part on land. Amphibians are slimy. Amphibians are cold-blooded that means their body temperature changes with the temperature outside. And as amphibians grow up, they go through metamorphosis.

Metamorphosis is when an animal changes its shape as it grows. Humans don’t go through metamorphosis – a baby human looks pretty much like an adult human, except babies are smaller. Perhaps you’ve noticed…or remember. Baby frogs, however, look way different from adult frogs. They have tails, they don’t have legs, and they have gills, which let them breathe underwater. As the baby frog grows, it forms legs, it loses its tail, and its gills change into lungs – presto, it’s a frog.

So hop to it and watch the “Amphibians” episode.

The Big Idea

• Amphibians are cold-blooded.
• Most amphibians live part of their life in water and part on land.
• Amphibians go through metamorphosis.

Did You Know That?

• Chameleons change color by changing the concentration and location of dark brown melanin molecules in their skin?
• The Japanese giant salamander is the biggest amphibian in the world – some measure more than five feet long?
• Axolotls are a species of amphibian that never go through metamorphosis? Some scientists call them the “Peter Pan” amphibians, because they never grow up.

Books of Science!

• “What Is an Amphibian?”by Robert Snedden. Published by Sierra Club Children’s Books, 1994.
• “Reptiles and Amphibians” by Catherine Herbert Howell. Published by National Geographic Nature Library, 1993.