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rowanlim
08-04-08, 04:33
This should be an interesting read, I just wanted to share it ;)

First Lungless Frog Found

The first recorded species of frog that breathes without lungs has been found in a clear, cold-water stream on the island of Borneo in Indonesia.

The frog, named Barbourula kalimantanensis, gets all its oxygen through its skin.

"Nobody knew about the lunglessness before we accidentally discovered it doing routine dissections," study lead author David Bickford, a biologist at the National University of Singapore, said in an email.

His colleague Djoko Iskandar at the Bandung Institute of Technology in Indonesia first discovered two specimens of the frog in 1978.

"Each specimen was deemed so valuable that scientists did not want to sacrifice the animals for dissection," Bickford said.

But the biologist immediately partially dissected several frogs when he found the species on a recent expedition to Borneo.

The team describes the peculiar frog in the May 6 issue of the journal Current Biology.

Evolutionary Oddity

Previously the only four-limbed creatures known to lack lungs were salamanders.

A species of earthwormlike, limbless amphibian called a caecilian is also lungless.

Tetrapods, or four-limbed creatures, that develop without lungs are rare evolutionary events, Bickford and colleagues write.

The trait in amphibians is likely an adaptation to life between water and land and their ability to respire through the skin.

The researchers suggest lunglessness in B. kalimantanensis may be an adaptation to the higher oxygen content in fast-flowing, cold water.

"Cold water can hold more dissolved oxygen than warm water," Bickford explained.

The frog also has a low metabolic rate, which means it needs less oxygen.

What's more, the species is severely flat compared to other frogs, which increases the surface area of the skin.

"Along with the fact that having lungs makes you more likely to be swept away in a fast-flowing streamóbecause you would floatóthis [is] a very strong context for the evolution of loss of lungs," Bickford said.

Unsurprising Find

David Wake is a biologist and expert in amphibian evolution at the University of California, Berkeley.

He said the finding of a lungless frog is unsurprising since tailed frogs are already known for their greatly reduced lungs.

Wake added that for most amphibians, the majority of gas exchange happens through the skin. A low but significant amount of respiration occurs via simple, sac-like lungs.

Most species, he noted, have mating calls that require lungs.

So biologists are unsure why a few species have entirely gotten rid of the organs, Wake said.

"This species is so rare that we know next to nothing concerning its biology," he wrote in an email. "But it is aquatic and lives in cold streams and doubtless has low basal metabolic rate."

Thus loss of lungs as an adaptation to the cold, fast-flowing water "seems like a rational hypothesis to me," he said.

Rare Frog

Further studies of the frog to test the hypothesis, however, may be hampered by the species' rarity and endangered habitat, according to Bickford and colleagues.

For instance, the frog's cold-stream habitat is being destroyed by illegal gold mining, Bickford said.

The mining activity makes the water cloudy with sediment and contaminates it with mercury.

In addition, much of the surrounding habitat is under threat from legal and illegal logging, which increases runoff into the streams.

"Most of the frog's presumably original range is now completely uninhabitable," Bickford said.

Further threats, he added, may come from changes in temperature and precipitation patterns due to climate change.

"This frog has a grim future and it is entirely our fault," Bickford said.

"It is our responsibility to try and remedy the situation."

Source (http://news.nationalgeographic.com/news/2008/04/080407-lungless-frog_2.html)

Here's a picture of the frog :D

http://i227.photobucket.com/albums/dd164/rowanlim/080407-lungless-frog_big.jpg

Looks pretty ordinary to me :p

aquaflute
08-04-08, 04:38
too bad it doesn't look like the delicious type of frog to me:o

rowanlim
08-04-08, 04:54
too bad it doesn't look like the delicious type of frog to me:o

Heheh I don't eat frogs but this doesn't encourage me to try...I mean I really like the fact that the environment forces the frog to change...to be lungless...I think that's pretty cool :D

Shrantellatessa
08-04-08, 05:29
That thing looks very sexy :p

Nice find, Jo :)

Capt. Murphy
08-04-08, 06:14
Hmm. It's eyes are in the front instead of the sides like most frogs. :pi:

I wonder if they make a sound - Like croaking or 'ribbit' ? :D

rowanlim
08-04-08, 06:39
Hmm. It's eyes are in the front instead of the sides like most frogs. :pi:

I wonder if they make a sound - Like croaking or 'ribbit' ? :D

I think they croak :D

Well there's this bizarre fish that has eyes in front, rather than at the sides...it looks like a human face :p

Flat-Faced Crawling Fish Discovered

April 3, 2008—After countless centuries, this odd anglerfish (right) may finally be ready for its close-up.

Discovered in Indonesia in January, the species has forward-looking eyes like a human and crawls rather than swims.

These and other traits suggest the fist-size animal may represent a new family of fishes, University of Washington fish expert Ted Pietsch announced on April 2, when this photo was released. DNA tests are needed for confirmation.

Pietsch first learned of the unnamed species from dive-facility operators on Ambon island, Indonesia. "I knew it had to be an anglerfish because of the leglike pectoral fins on its sides," he said in a statement.

But the new species lacks the trademark forehead "lure" that other anglerfish use to attract prey.

The fish's forward-facing eyes seem to be a first, even to Pietsch, a 40-year veteran of fish research.

The fish's knack for squeezing into coral crevices may explain why it's escaped notice until now—a low profile that isn't likely to last.

"Seeking out these fish is probably going to be like the holy grail of divers for a while," Ambon Island-based dive operator Randolph Shorten said in a statement.

Link (http://news.nationalgeographic.com/news/2008/04/080403-fish-photo.html)

Here's how the fish looks like:

http://i227.photobucket.com/albums/dd164/rowanlim/080403-fish-photo_PIN.jpg

Interesting, eh? :p

kryptonite23
08-04-08, 06:55
Great FindS JO!! :tmb:

Earthcane
08-04-08, 06:56
Maybe he's been eating a little too much Gillyweed....:whi:

:D

Drone
08-04-08, 11:57
nice crazy frog thanks for sharing Jo, it's very interesting :)
About crawling fish I've heard b4 :)

Greenkey2
08-04-08, 12:31
Nature never ceases to surprise :D :tmb:

Muhammad
08-04-08, 14:26
It is a delicious frog, you must eat.

TheStoryteller
08-04-08, 14:28
a very interesting read :tmb:

Larapink
08-04-08, 14:32
Thats really interesting. :tmb:

cococomics_pres
08-04-08, 15:41
Wow awesome find. That flat-faced crawling fish thing is crazy. Underwater animals never cease to surprise/freak me out! :D

rowanlim
09-04-08, 03:24
Wow awesome find. That flat-faced crawling fish thing is crazy. Underwater animals never cease to surprise/freak me out! :D

Yeah the flat-faced crawling fish looks like a HUMAN...:p

star-dust
09-04-08, 06:37
Wow,
I love stuff like this!
It's amazing...
animals.
Imagine all the other
secrets nature has
hidden around the world.:)