A frog is any member of 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 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...
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