NUS team makes history by finding frog with no lungs
Kalimantan find is only the 4th creature with backbones known to breathe without lungs
By Shobana Kesava
ONE OF A KIND: DrDavid Bickford holds preserved specimens of the endangered species of lungless frog that his team found in Indonesia. -- ST PHOTO: LAU FOOK KONG
SINGAPORE scientists have discovered a lungless frog that breathes through its skin - a find that makes evolutionary history.
The aquatic frog is affectionately called Barbie - short for its scientific name Barbourula kalimantanensis. It was found in two mountain rivers in the heart of Kalimantan last August.
A group of nine researchers, led by evolutionary biologist David Bickford from the National University of Singapore (NUS), found the flat, dark brown frogs with golden specks under smooth rocks in clean, cool and fast-flowing water.
Their findings are set to be published next month.
Since animals first waddled onto land eons ago, only three other creatures with backbones - two groups of salamanders and a single species of the earthworm-like caecilians - have been known to forsake their lungs.
Dr Bickford, 39, said Barbie absorbs oxygen dissolved in the water through its skin.
Barbourula kalimantanensis
Length: 38mm
Weight: 6.5g
Reproduction method: Unknown
Home: Found on the bed of cold, clean rivers
Body temperature: 14 to 17 deg C
Respiration: To stay safely on the river bed, away from swirling currents, it has done away with air-filled lungs which would increase its buoyancy. Oxygen passes into its bloodstream through the skin.
Vision: Forward-facing eyes make the frog more streamlined and help it pinpoint prey.
Food: Scientists believe it is a fierce predator feeding on beetle larvae three times its length.
'The discovery is not so much a surprise to the scientific community as much as a surprise that it has taken so long to find it,' DrBickford said.
One reason could be that the frog resides deep in mountain rivers and is fully aquatic.
A fisherman first took a Barbie to Indonesian scientist Djoko Iskandar in Kalimantan in 1978. He had been searching for the animal ever since.
Part of the NUS team last August, DrDjoko co-authored the scientific paper with DrBickford.
'Djoko was near tears when we found them after all those years of searching,' said DrBickford.
The specimens the NUS team discovered were well over 50km from where the first frogs were spotted by local fishermen.
Their original wading grounds had become prime gold-mining and logging territory.
'They must have been forced upstream from their original habitats...so we got to the end of the logging road and started the search,' added DrBickford.
He hopes the find will help spur research into South-east Asian wildlife, much of which is threatened by development.
'Frogs are a clear indication of how degraded our environment is, so if people who know the terrain can help us discover what we have and preserve it, my work in conservation will be worth it,' he said.
Indonesian zoologist Indraneil Das, who studies amphibians and reptiles, said the discovery of a lungless frog could stir up national interest.
'This shows us yet another innovation by amphibians. If the findings are read by the government and if it does something about them by way of conservation...that will be a good thing for all concerned, except perhaps the gold-miners.'
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