Frog Facts

Cards · 50

Cutaneous respiration

Frogs absorb over half their oxygen directly through permeable skin, requiring moist conditions to survive.

Permeable skin hydration

Frogs do not drink water with their mouths; they absorb all necessary moisture through an abdominal patch.

Skin shedding and consumption

Most frogs shed their outer skin weekly and eat it immediately to recycle valuable proteins and nutrients.

Nictitating membrane

A transparent third eyelid allows frogs to see clearly underwater while protecting eyes from debris.

Eye depression during swallowing

Frogs pull their large eyeballs down into their sockets to physically push food down their throats.

360-degree panoramic vision

Protruding, bulbous eyes provide nearly a full sphere of vision to detect incoming aerial and terrestrial predators.

Tympanum hearing organ

External circular membranes behind the eyes transmit sound vibrations directly to the frog inner ear.

Vocal sac amplification

Male frogs inflate elastic throat pouches like resonance chambers to project mating calls across miles.

Tadpole metamorphosis

Thyroid hormones trigger tadpoles to reabsorb gills and tails while developing limbs and adult lungs.

Amplexus mating embrace

Males grasp females from behind for hours or days, ensuring immediate fertilization as eggs are released.

Goliath frog size

Native to Equatorial Guinea and Cameroon, this largest frog reaches 13 inches and weighs up to seven pounds.

Paedophryne amauensis scale

At just 7.7 millimeters long, this Papua New Guinean leaf-litter dweller is the smallest known vertebrate.

Wood frog cryopreservation

High glucose concentrations prevent cellular damage while up to two-thirds of body water freezes solid in winter.

Golden poison frog toxicity

A single two-inch specimen produces enough batrachotoxin to kill ten adult humans or 20,000 mice.

Dietary origin of dart toxins

Poison dart frogs synthesize lethal defensive toxins from wild diets of formicine ants, beetles, and mites.

Bioindicator sensitivity

Highly porous skin makes amphibians primary bellwethers for environmental pollution and climate disruption.

Chytridiomycosis crisis

The fungal pathogen Batrachochytrium dendrobatidis thickens skin, causing cardiac arrest across hundreds of species.

Glass frog translucency

Clear abdominal skin hides outlines against sunlit leaves and reveals functioning internal organs.

Kangaroo frog pouch

The pouched frog carries developing fertilized eggs safely tucked inside a specialized dorsal brood pouch.

Surinam toad gestation

Females absorb eggs into pocketed back skin, where offspring incubate and emerge as fully formed toadlets.

Gastric-brooding frog reproduction

Extinct Australian females halted stomach acid production to gestate developing young entirely in their stomachs.

Tongue attachment anatomy

Unlike humans, frog tongues attach to the front of the lower jaw, flipping outward rapidly like a catapult.

Non-Newtonian frog saliva

Saliva liquefies upon impact to coat prey, then instantly thickens into an adhesive grip as it retracts.

Prey capture speed

A frog tongue strikes insect prey in under 0.07 seconds, five times faster than a human eye blink.

Maxillary teeth function

Upper jaw ridges lack chewing power, serving purely to grip struggling prey before swallowing it whole.

Absence of mandibular teeth

True frogs lack teeth on the lower jaw, except for the rare marsupial frog Gastrotheca guentheri.

Frog jump mechanics

Elastic leg tendons store energy like spring-loaded bows, releasing far more explosive power than muscle alone.

Toe pads in tree frogs

Microscopic hexagonal column patterns secrete lubricating mucus, generating strong capillary wet adhesion.

Desert spadefoot estivation

Burrowed up to a meter deep in dry soil, spadefoots remain dormant in mucus cocoons for multiple drought years.

Explosive desert breeding

Torrential desert rains awaken spadefoot toads to breed immediately before ephemeral desert pools evaporate.

Tadpole cannibalism morphs

In overcrowded, drying pools, some spadefoot tadpoles develop huge heads to devour competing herbivore siblings.

Waxy monkey frog sun protection

Arboreal tree frogs rub lipid secretions over their bodies using their legs to prevent arid desiccation.

Hairy frog defensive bones

When threatened, Trichobatrachus robustus intentionally breaks toe bones, forcing sharp claws through the skin.

Corroboree frog patterning

Vibrant black and yellow dorsal stripes warn predators of indigenous alkaloid neurotoxins produced organically.

True toad parotoid glands

Large swollen glands behind toad eyes eject milky bufotoxin containing cardioactive steroids when bitten.

Aposematism in anurans

Brilliant crimson, orange, and sapphire hues visually warn diurnal predators of deadly cutaneous poisons.

Batesian mimicry in harmless frogs

Non-toxic species mimic bright warning coloration patterns of toxic poison dart frogs to deter predators.

Wallace's flying frog gliding

Oversized webbed hands and feet act as parachutes, allowing leaps exceeding fifty feet between canopy trees.

Paradoxical frog shrinkage

Ten-inch tadpoles shrink down into modest three-inch adults during final anatomical metamorphosis.

Xenopus laevis pregnancy testing

Human chorionic gonadotropin in pregnant urine triggers African clawed frogs to lay eggs within twelve hours.

Clawed frog evolutionary uniqueness

African clawed frogs lack true tongues and vocal cords, instead clicking using internal laryngeal apparatus.

Bullfrog appetite breadth

American bullfrogs consume anything fitting their gape, including rodents, bats, venomous snakes, and birds.

Bane of cane toad introduction

Imported to Australia to consume sugar cane beetles, invasive toads poisoned hundreds of native apex predators.

Male Darwin's frog vocal sac brooding

Fathers ingest fertilized eggs, incubating developing froglets safely inside enlarged vocal sacs until birth.

Coquí frog sonic volume

Native Puerto Rican coquí mating calls reach 100 decibels, rivaling jackhammers and disrupting residential sleep.

Lack of ribs in true frogs

Most anurans lack functional thoracic ribs, relying entirely on flexible, lightweight vertebral processes.

Urostyle pelvic adaptation

Fused caudal vertebrae form a rigid rod, stabilizing the pelvis to absorb tremendous shock upon landing.

Biofluorescence in tree frogs

South American polka-dot tree frogs absorb ultraviolet light and re-emit bright blue-green luminescence.

Epipedobates anthonyi painkiller

Epibatidine isolated from Ecuadoran poison frogs acts as an analgesic 200 times stronger than morphine.

Tadpole filter feeding

Aquatic larvae use fine branchial filters to strip suspended phytoplankton and detritus from murky water columns.