Frog

From Wikipedia, the free encyclopedia

This article is about the group of amphibians. For other uses, see Frog (disambiguation).

Frogs Temporal range:

Early Jurassic - Present, 200–0 Ma PreЄ

Є O S D C P T J K Pg N

Various types of frogs.

Scientific classification

Kingdom: Animalia

Phylum: Chordata

Class: Amphibia

Clade: Salientia

Order: Anura Duméril, 1806 (as Anoures)

Suborders

Archaeobatrachia

Mesobatrachia

Neobatrachia

–

List of Anuran families

Native distribution of frogs (in green)

Frogs are a diverse and largely carnivorous group of short-bodied, tailless amphibians

composing the order Anura (Ancient Greek an-, without + oura, tail). The oldest fossil "proto-

frog" appeared in the early Triassic of Madagascar, but molecular clock dating suggests their

origins may extend further back to the Permian, 265 million years ago. Frogs are widely

distributed, ranging from the tropics to subarctic regions, but the greatest concentration of

species diversity is found in tropical rainforests. There are approximately 4,800 recorded species,

accounting for over 85% of extant amphibian species. They are also one of the five most diverse

vertebrate orders.

The body plan of an adult frog is generally characterized by a stout body, protruding eyes, cleft

tongue, limbs folded underneath, and the absence of a tail in adults. Besides living in fresh water

and on dry land, the adults of some species are adapted for living underground or in trees. The

skin of the frog is glandular, with secretions ranging from distasteful to toxic. Warty species of

frog tend to be called toads but the distinction between frogs and toads is based on informal

naming conventions concentrating on the warts rather than taxonomy or evolutionary history;

some toads are more closely related to frogs than to other toads. Frogs' skins vary in colour from

well-camouflaged dappled brown, grey and green to vivid patterns of bright red or yellow and

black to advertise toxicity and warn off predators.