Let’s learn about amphibians

These animals often live double lives — first as water dwellers, then as landlubbers

a blue frog sits on a mossy surface in a body of water

Amphibians include frogs — such as this blue poison arrow frog — as well as toads, salamanders and weird, wormlike creatures called caecilians.

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Humans change a lot as they grow from kids into adults. But those changes are nothing compared with the transformation experienced by many amphibians.

These animals get their name from the Greek word for “double life.” Most amphibians start out as larvae. They use tails to paddle around underwater and breathe through gills like fish. But as they grow up, amphibians go through a drastic body change. This is called metamorphosis. Adult amphibians usually grow lungs and some lose their tails. 

Frogs, toads and newts are amphibians. So are some lesser-known species, such as hellbenders. These giant salamanders are sometimes called “snot otters” for their slippery coating of protective slime. Perhaps even stranger are caecilians. These legless amphibians look like worms or snakes. They live underground or underwater and can grow up to nearly 1.5 meters (five feet) long.

In all, there are about 6,000 known species of amphibians. These creatures are vertebrates, meaning they have spines. They also are cold-blooded. Amphibians provide natural pest control by eating mosquitoes and other insects. They also make a meal for many birds, mammals and even some meat-eating plants.

Most amphibians have thin, moist skin. Absorbing oxygen through that delicate skin helps them breathe. And soaking up water keeps them hydrated. But that delicate skin also makes amphibians very vulnerable to changes in the environment. In fact, the populations of more than four in every 10 amphibian species are shrinking. Nearly one-third of all amphibin species is threatened with going extinct. The reasons include pollution, climate change and habitat loss.

Another key amphibian killer is a fungal infection. It’s got a long name — chytridiomycosis (Kih-TRIH-dee-my-KOH-sis). It has been wiping out amphibians around the globe. Scientists are trying to save hard-hit species by breeding the remaining members. Learning how some amphibians survive the deadly fungus could also help save others from the scourge. 

Want to know more? We’ve got some stories to get you started:

Pumpkin toadlets can’t hear themselves talk Tiny orange frogs make soft chirping sounds in the forests of Brazil. Their ears, however, cannot hear them. (10/31/2017) Readability: 7.0

Toxic germs on its skin make this newt deadly Bacteria living on the skin of some rough-skinned newts make tetrodotoxin. This paralyzing poison is also found in pufferfish. (6/23/2020) Readability: 7.0

Flu fighter found in frog slime A protein found in the mucus secretions of an Indian frog can take down a type of flu virus. (5/10/2017) Readability: 7.0

A combination of threats is threatening the world’s amphibians. Chief among them are pollution, climate change and disease.

Explore more

Scientists Say: Amphibian

Scientists Say: Parthenogenesis

Analyze This: Amphibian populations are on the decline

Caecilians: The other amphibian

Lots of frogs and salamanders have a secret glow

Why some frogs can survive killer fungal disease

A Bolivian frog species returns from the dead

Hellbenders need help!

Meat-eating pitcher plants feast on baby salamanders

Mosquito repellant could pose risks to baby salamanders

Congolese toads may avoid predators by copycatting deadly vipers

Toxic toads pose threat to Madagascar’s predators

Hunting hidden salamanders with eDNA


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Want to support amphibian conservation efforts? Join FrogWatch USA. Volunteers in the program listen for frog and toad calls in the evening and add their observations to an online database. These data from citizen scientists can help researchers understand the  health of amphibian populations across the country.

Maria Temming is the Assistant Managing Editor at Science News Explores. She has bachelor's degrees in physics and English, and a master's in science writing.

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