Science, Tech, Math › Animals & Nature Top 10 Facts About Frogs Share Flipboard Email Print Frogs have worldwide distribution with the exception of the polar regions, some oceanic islands, and the driest of deserts. Ferdinando Valverde / Getty Images. Animals & Nature Amphibians Birds Habitat Profiles Mammals Reptiles Wildlife Conservation Insects Marine Life Forestry Dinosaurs Evolution View More By Laura Klappenbach Ecology Expert M.S., Applied Ecology, Indiana University Bloomington B.S., Biology and Chemistry, University of Illinois at Urbana-Champaign Laura Klappenbach, M.S., is a science writer specializing in ecology, biology, and wildlife. our editorial process Laura Klappenbach Updated February 22, 2019 Frogs are the most familiar group of amphibians. They have worldwide distribution with the exception of the polar regions, some oceanic islands, and the driest of deserts. 10 Facts About Frogs Frogs belong to the Order Anura, the largest of the three groups of amphibians. There are three groups of amphibians. Newts and salamanders (Order Caudata), Caecilians (Order Gymnopiona), and frogs and toads (Order Anura). Frogs and toads, also referred to as anurans, represent the largest of the three amphibian groups. Of the approximately 6,000 species of amphibians, about 4,380 belong to the Order Anura.There is no taxonomic distinction between frogs and toads. The terms "frog" and "toad" are informal and do not reflect any underlying taxonomic differences. In general, the term toad is used to apply to anuran species that have rough, warty skin. The term frog is used to refer to anuran species that have smooth, moist skin.Frogs have four digits on their front feet and five on their rear feet. The feet of frogs varies depending on their habitat. Frogs that inhabit wetter environments have webbed feet while tree frogs have discs on their toes that help them grasp to vertical surfaces. Some species have claw-like structures on their back feet that they use for burrowing.Leaping or jumping is used as a means for evading predators, not for normal movement. Many frogs have large, muscular back limbs that enable them to launch themselves into the air. Such leaping is rarely used for normal locomotion but instead provides frogs with a way of escaping predators. Some species lack these long muscular back limbs and instead have legs better adapted to climbing, swimming, or even gliding.Frogs are carnivores. Frogs feed on feed on insects and other invertebrates. Some species also feed on small animals such as birds, mice, and snakes. Many frogs wait for their prey to come within range and then lunge after them. A few species are more active and follow in pursuit of their prey.The life cycle of a frog consists of three stages: egg, larva, and adult. As the frog grows it moves through these stages in a process known as metamorphosis. Frogs are not the only animals to undergo metamorphosis, most other amphibians also undergo remarkable changes throughout their life cycles, as do many species of invertebrates.Most species of frogs have a large visible ear drum on each side of their head called a tympanum. The tympanum is located behind the frog's eye and serves to transmit sound waves to the inner ear and thereby keep the inner ear protected from water and debris.Each species of frog has a unique call. Frogs make vocalizations, or calls, by forcing air through their larynx. Such vocalizations usually function as mating calls. Males often call together in a loud chorus.The largest living species of frog in the world is the Goliath frog. The Goliath frog (Conraua goliath) can grow to lengths of 13 inches (33 cm) and can weigh as much as 8 lb (3 kg).Many frogs are at risk of extinction. Many frog species are at risk of extinction due to habitat destruction and infectious diseases such as chytridiomycosis.