World's Smallest Frog Discovered

Researchers have discovered two species of what may be the world’s smallest frog species. As described in the journal PloS ONE, these new species of mini, terrestrial frogs were found on the island of New Guinea, and represent not only the smallest known frog but possibly also the smallest known vertebrate species (animal with a backbone).  Both new species are members of the recently described genus Paedophryne, the four species of which are among the ten smallest known frog species. They attain an average body size of only 7.7 mm (range 7.0–8.0 mm), less than the size of an M&M.

Photo courtesy Louisiana State University/PloS ONE

The researchers believe that the frogs have evolved their teeny size in a unique ecological niche: the leaf litter of tropical forests that remains moist year round. The frogs eat even tinier creatures (mites etc) that most other frogs don’t exploit. They are well camouflaged among leaves on the forest floor, and have evolved calls resembling those of insects.

According to the researchers, other places in the world that also feature dense, moist leaf litter tend to possess such small frog species, indicating that amphibians are well placed to occupy this ecological niche.

Before the Paedophrynes were found, the title of “world’s smallest frog” was bestowed on the Brazilian gold frog (Brachycephalus didactylus) and its slightly larger Cuban relative, the Monte Iberia Eleuth (Eleutherodactylus iberia). They both measure less than 1cm long.

For more information:

Rittmeyer EN , Allison A , Gründler MC , Thompson DK , Austin CC , 2012 Ecological Guild Evolution and the Discovery of the World’s Smallest Vertebrate. PLoS ONE


Amazing Frog Dads

Most animal dads aren’t too involved with their offspring (human dads, excepted of course). But two species of frogs called microhylids are devoted dads, and in fact, carry their their brood of up to 25 froglets piggyback style through the rain forest of Papua New Guinea. The frogs were discovered by evolutionary biologist David Bickford.

While most frogs start their lives as tadpoles, these frogs bypass that stage and go straight from larvae to miniature versions of adults while still inside the egg. This allows them to reproduce in areas without bodies of water nearby.

After the mother frog lays the eggs, she hops off while Dad watches over the clutch, warding off predators, and keeping the eggs moist for about a month.

copyright David Bickford

copyright David Bickford

After the froglets hatch from the eggs, they hop on Dad’s back. He carries them by night through the leaf litter in the rain forest. The froglets have a free ride until they grow up a bit and can live independently (hmmm…sounds familiar).