Extinct Frog Cloned: Amphibian Embryos From 'Mouth-Birthing' Species Grown In Lab

A bizarre species of frog that went extinct decades ago has been brought back to life.

In an effort known as the Lazarus Project, scientists at the University of New South Wales in Sydney, Australia cloned Rheobatrachus silus, which is believed to have died out in the mid-1980s.

And if you think cloning is weird, the creature itself is even weirder. The little amphibian delivers frog babies straight from its mouth by swallowing its own fertilized eggs and then regurgitating fully formed froglets from its stomach. Dr. Mike Archer, a professor at the university and a Lazarus researcher, detailed the species' 'gastric brooding' during a presentation at TedxDeExtinction on March 15 in Washington, D.C.

“We are watching Lazarus arise from the dead, step by exciting step,” Archer said in a written statement released by the university. “We’ve reactivated dead cells into living ones and revived the extinct frog’s genome in the process. Now we have fresh cryo-preserved cells of the extinct frog to use in future cloning experiments. We’re increasingly confident that the hurdles ahead are technological and not biological and that we will succeed. Importantly, we’ve demonstrated already the great promise this technology has as a conservation tool when hundreds of the world’s amphibian species are in catastrophic decline.”

The researchers created fresh embryos using tissue samples taken from R. silus specimens prior to the species' extinction. Cell nuclei from the samples were embedded in eggs from another frog species, Mixophyes fasciolatus, at which point some of the eggs began to spontaneously divide and grow into a basic embryo.

"This is the first time this technique has been achieved for an extinct species," Michael Mahony, a Lazarus researcher and life sciences professor at Australia's Newcastle University, told the Sydney Morning Herald.

"We’ve done the first cross-species cloning in frogs," Archer told The Huffington Post in an email, "and as far as I know are the first to have revitalized a totally ‘dead’ non-cryopreserved genome of an extinct species. That's vitally important in the direction of helping to conserve so many endangered frogs tipping over the edge at the moment."

For those keeping score, the Pyrenean ibex, an extinct species of wild Spanish goat, was also briefly brought back from extinction via cloning in 2009.

Following announcement of the ibex's birth, environmentalists cautioned that de-extinction via cloning is far from an ideal solution for reintroducing populations of endangered animals to the world.

Speaking of the ibex clone to National Geographic in 2010, David Wildt, a senior scientist at the Smithsonian's National Zoological Park in Washington, D.C., said there are "vastly more effective and logical approaches" to preserving threatened species.

Namely, helping ensure they don't go extinct in the first place.



Extinct Prehistoric Animals