A frog is any member of a diverse and largely carnivorous group of
short-bodied, tailless amphibians composing the order Anura (ανοὐρά,
literally without tail in Ancient Greek).
The oldest fossil "proto-frog" Triadobatrachus is known from the Early
Triassic of Madagascar, but molecular clock dating suggests their split
from other amphibians 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 in tropical rainforest.
Frogs account for around 88% of extant amphibian species. They are also
one of the five most diverse vertebrate orders. Warty frog species tend
to be called toads, but the distinction between frogs and toads is
informal, not from taxonomy or evolutionary history.
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