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Early Warning Sign?

Emperor newt with eggs Amphibians around the world are vanishing—and may signal danger to our global ecosystem's health. Why?

Amphibians feel the effects of environmental changes long before we do, partly because of their sensitive skin and watery way of life. In fact, one-third of all known amphibian species are threatened with extinction. The greatest threats are pollution and climate change, but disease, habitat destruction and fragmentation, and invasive species are also affecting amphibians.

The IUCN's Amphibian Specialist Group is working to study, save, restore, and manage amphibians and their habitats around the world.

Sensitive Skin

Amphibians breathe partly through their skin—taking in vital oxygen. But the permeability that makes their skin special also makes amphibians sensitive to pollution in the soil, air, and water.

Zoom in on the White's tree frog below to see how wet the skin is. You can even see the pores.

Leading a Double Life

Amphibian means "double life" in Greek. Many amphibians start life in the water, and, through a dramatic transformation (metamorphosis), develop into adults that live mostly on land.

Tadpole with arms and legs

As the tadpole starts changing into a frog, hind legs grow. Soon front legs also appear. Later, the tail shrinks and the tadpole develops lungs—then it can come out on land.

View next stage of metamorphosis

African pancake tortoise
African pancake tortoise
Malacochersus tornieri
Aldabra tortoise
Aldabra tortoise
Geochelone gigantea
Alligator snapping turtle
Alligator snapping turtle
Macroclemys temminckii
Australian snake-necked turtle
Australian snake-necked turtle
Chelodina longicollis
Black ratsnake
Black ratsnake
Elaphe obsoleta (obsoleta)
Boa constrictor
Boa constrictor
Boa constrictor
Brazilian rainbow boa
Brazilian rainbow boa
Epicrates cenchria (cenchria)
Burmese python
Burmese python
Python molurus (bivittatus)
Cottonmouth
Cottonmouth
Agkistrodon piscivorus
Cuban crocodile
Cuban crocodile
Crocodylus rhombifer
Eastern box turtle
Eastern box turtle
Terrapene carolina
Emerald tree boa
Emerald tree boa
Corallus caninus
Emperor newt
Emperor newt
Tylototriton shanjing
European glass lizard
European glass lizard
Ophisaurus apodus
Everglades ratsnake
Everglades ratsnake
Elaphe obsoleta rossalleni
Eyelash palm pitviper
Eyelash palm pitviper
Bothriechis schlegelii
Florida softshell turtle
Florida softshell turtle
Apalone ferox
Gaboon viper
Gaboon viper
Bitis gabonica
Gharial (Gavial)
Gharial (Gavial)
Gavialus gangeticus
Gila monster
Gila monster
Heloderma suspectum
Grand Cayman iguana
Grand Cayman iguana
Cyclura lewisi
Greater siren
Greater siren
Siren lacertina
Green anaconda
Green anaconda
Eunectes murinus
Green iguana
Green iguana
Iguana iguana
Green tree python
Green tree python
Morelia viridis
Inland bearded dragon
Inland bearded dragon
Pogona vitticeps
King cobra
King cobra
Ophiophagus hannah
Leopard gecko
Leopard gecko
Eublepharis macularius
Mangrove snake
Mangrove snake
Boiga dendrophila
Matamata turtle
Matamata turtle
Chelus fimbriatus
Northern blue-tongued skink
Northern blue-tongued skink
Tiliqua scincoides
Northern pine snake
Northern pine snake
Pituophis melanoleucus
Oriental fire-bellied toad
Oriental fire-bellied toad
Bombina orientalis
Red-tailed ratsnake
Red-tailed ratsnake
Gonyosoma oxycephala
Timber rattlesnake
Timber rattlesnake
Crotalus horridus
Tokay gecko
Tokay gecko
Gekko gecko
Veiled chameleon
Veiled chameleon
Chamaeleo calyptratus
White's tree frog
White's tree frog
Pelodryas caerulea
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Snake Habitat
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Lizard Defense
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Snake Skin
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Reptile Diet
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Crocodilian
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Reptile Moves
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Gharial Conservation
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Zoo Breeding
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Crocodile Conservation
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Reptile Vision
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Boas
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Iguana Conservation
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Constriction
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Reptile Conservation
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Venom
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Turtle Conservation
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Amphibian Conservation
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Aldabra Tortoise
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Water Quality
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