Frogs and Toads

Thin skin, big voices and wild life cycles.

Frogs and toads breathe partly through their skin and usually start life as swimming tadpoles that later change into land-dwelling adults, although a few species skip stages. That thin, moist skin explains a lot: it is why some species are poisonous, why many are sensitive to pollution, and why a single fungus has hit amphibians so hard.

Each article takes one species and one big idea: a frog you can almost see through, a frog that survives being frozen, a call that carries across a pond, a parent that carries the eggs. The category closes with the chytrid fungus, the disease behind many recent amphibian declines.

Frog and toad statuses are reassessed as new surveys come in, so you will see a consultation date on every conservation note. We do not give advice on catching or keeping wild amphibians.

Nine questions in this category

  1. Toxic skin
  2. Glass frogs
  3. Freezing frogs
  4. Calls
  5. Metamorphosis
  6. Frog or toad
  7. Parental care
  8. Extreme sizes
  9. Chytrid fungus

The species in this category

Play a round with any of them in the Terrarium to unlock the full article.

IUCN LC

American bullfrog

Lithobates catesbeianus

The American bullfrog starts as a floating film of eggs and may spend a year or more as a large tadpole before it transforms. We follow each stage…

IUCN LC

American toad

Anaxyrus americanus

Scientists file every toad under frogs, yet the word still points to a real group, the true toads. The American toad is a handy test case for the…

IUCN EN

Darwin's frog

Rhinoderma darwinii

Male Darwin's frogs guard their eggs, then take the young into a vocal sac and carry them for roughly six to ten weeks, depending on the source.…

IUCN LC

Fleischmann's glass frog

Hyalinobatrachium fleischmanni

Fleischmann's glass frog has a see-through belly, and a 2022 study found that sleeping frogs tuck about 89% of their red blood cells into the…

IUCN EN

Golden poison frog

Phyllobates terribilis

The golden poison frog of Colombia stores batrachotoxins in its skin, but the research points to its diet, not its own glands, as the source.…

IUCN EN

Goliath frog

Conraua goliath

The goliath frog is the largest living frog, with adults commonly 20 to 30 centimeters long and the largest somewhat more. The smallest known…

IUCN CR

Panamanian golden frog

Atelopus zeteki

The Panamanian golden frog is a bright yellow frog of Panama that Smithsonian's National Zoo describes as extinct in the wild. Sources name the…

IUCN LC

Spring peeper

Pseudacris crucifer

Male spring peepers fill early-spring nights with a single clear whistle from an unusually large vocal sac, while females listen and choose. We…

IUCN LC

Wood frog

Lithobates sylvaticus

The wood frog survives winter partly frozen: ice forms under its skin, its heart stops, and glucose and urea protect its cells until spring. We…