What Are Amphibians and Where Are They Found?

Amphibians were the first vertebrate animals to leave the water and begin colonizing land. However, they never completely abandoned the aquatic environment, since their survival and reproduction still depend on water. One of their most unique traits is metamorphosis—a process through which they transform from aquatic larvae (such as tadpoles) into terrestrial adults, changing not only their appearance but also their way of breathing and feeding.

This article explains what amphibians are, where they are found, and highlights different species that live in contrasting climates around the world.

What Are Amphibians and Where Do They Live?

Amphibians are cold-blooded vertebrates with a life cycle that alternates between water and land.

• Larvae (such as tadpoles) usually live in water and breathe through gills.

• Adults move to land, breathing mainly through lungs and skin.

Because they are ectothermic (cold-blooded), amphibians cannot regulate a constant body temperature. As a result, they are rare in extremely cold habitats such as the Arctic and Antarctica. Fossil records, however, show that amphibians once lived there in prehistoric times when the climate was warmer.

Main groups of amphibians

Amphibians are divided into three orders, each with distinct adaptations:

1. Gymnophiona (Caecilians or Apodans)

• Worm-like, limbless amphibians.

• Mostly live underground in tropical and subtropical soils.

• Least tolerant to cold climates.

2. Anura (Frogs and Toads)

• Have strong legs for jumping, but no tail.

• This group is the most diverse and widely distributed.

3. Caudata (Salamanders, Newts, and Axolotls)

• Elongated bodies with tails.

• Some species remain aquatic for their entire lives.

Amphibians in Cold Regions

Few amphibians survive in extremely cold climates. Notable exceptions include:

• Siberian Salamander (Salamandrella keyserlingii) – found in northern Siberia, capable of surviving freezing conditions.

• Wood Frog (Lithobates sylvaticus) – inhabits Alaska and northern Canada, known for producing antifreeze-like substances in its cells to endure winter.

Adaptations include hibernating beneath ice during winter or producing internal chemicals to prevent ice crystals from forming inside their bodies.

Amphibians of the Taiga (Boreal Forest)

The boreal forest offers slightly milder temperatures, allowing more amphibians to thrive. Common examples include:

• Green Frog (Pelophylax perezi)

• Leopard Frog (Lithobates pipiens)

• Wood Frog (Lithobates sylvaticus)

• American Toad (Anaxyrus americanus)

• Blue-spotted Salamander (Ambystoma laterale)

• Fire Salamander (Salamandra salamandra)

• Eastern Newt (Notophthalmus viridescens)

Amphibians of Steppes and Deserts

Steppes, savannas, and deserts are dry environments with very little fresh water, making them inhospitable for most amphibians. Still, certain toads have developed special adaptations to survive:

• Water conservation: storing urine and reabsorbing water through their skin.

• Burrowing: staying underground during dry periods and surfacing only when rains arrive.

Examples include:

• Red-spotted Toad (Anaxyrus punctatus)

• Green Toad (Bufotes viridis)

• Spadefoot Toad (Pelobates cultripes)

• Mexican Burrowing Toad (Rhinophrynus dorsalis)

• Natterjack Toad (Epidalea calamita)

Amphibians of Mediterranean Forests

Mediterranean climates are mild, with more abundant freshwater sources. Amphibians are relatively common here, such as:

• Common Toad (Bufo bufo)

• Spadefoot Toad (Pelobates cultripes)

• Green Frog (Pelophylax perezi)

• European Tree Frog (Hyla arborea)

• Fire Salamander (Salamandra salamandra)

• Marbled Newt (Triturus marmoratus)

Amphibians of Tropical and Subtropical Regions

The tropics are the richest habitats for amphibians, thanks to high rainfall and warm temperatures.

• Frogs dominate, many with bright colors and toxic skin.

• Red-eyed Tree Frog (Agalychnis callidryas)

• Poison Dart Frogs (Dendrobatidae)

• Caecilians (Gymnophiona) are also widespread here, though rarely seen because they live underground or beneath leaf litter.

Conclusion

• Amphibians are cold-blooded vertebrates with a dual life cycle (aquatic larvae + terrestrial adults).

• They thrive in warm and humid regions but are scarce in extremely cold or dry habitats.

• Distribution by climate:

• Polar regions: almost absent (only fossils).

• Cold zones: rare, with specialized survivors like the Siberian Salamander.

• Deserts: only highly adapted burrowing toads.

• Temperate and Mediterranean zones: diverse species of frogs, toads, salamanders, and newts.

• Tropics: the highest biodiversity, with colorful and toxic species.

Amphibians are essential indicators of ecosystem health. Protecting them means preserving both aquatic and terrestrial habitats that sustain countless other forms of life.

animal tags： amphibians