Habitat: native to Queensland in eastern Australia
Status: Extinct… for now?
First described in 1973 by David Liem, the bizarre mouth-brooding or Gastric-brooding Frog (Rheobatrachus) was the name given to two different but very similar species of frog that were known for their unique reproductive behavior. What would happen is the eggs would be fertilized externally and then the female would scoop them up into her mouth and SWALLOW them. The eggs were coated in a substance called prostaglandin, which causes the female to stop making stomach acid so that the eggs can safely develop in her tum tum. She would essentially convert her stomach into a uterus. No big deal.
It was recorded – back when these frogs were still alive – that tadpole development took approximately 6 weeks, during which time the size of the mother’s stomach continued to increase until the tadpoles largely filled her body cavity. Her lungs even deflated in order to make extra room! That meant breathing relied more upon gas exchange through the skin rather than via her lungs. Now that’s a sacrifice only a mother would make.
When the tadpoles were completely developed the mother would, for lack of a better term, vomit them up. They were 100% formed at this point and ready to hop into the world as mini Gastric-brooding Frogs! Ah-mazing. Sadly, the frogs went extinct in the mid 1980’s for unknown reasons, though it’s thought that habitat loss and degradation, pollution, and some diseases may have contributed to its unfortunate end.
But, not so fast! There may be hope for these incredible frogs yet as scientists have taken the first step in trying to clone, and thereby resurrect, the extinct species. From ABC News:
In what became known as the ” Lazarus Project” at the University of Newcastle in Australia, scientists have resurrected the genome of a gastric-brooding frog, which became extinct in 1983. Also knows as Platypus frogs, the female amphibian, after external fertilization by the male, would swallow its eggs, brood its young in its stomach and gave birth through its mouth.
“We are watching Lazarus arise from the dead, step by exciting step,” Professor Mike Archer, a Lazarus Project team leader, said in a statement. “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.”
The team recovered cell nuclei from tissues collected in 1970 that were kept in a freezer, according to the university. Researchers took donor eggs from the distantly related great barred frog, and replaced their nuclei with dead nuclei from the gastric-brooding frog.
The embryos only lived for a few days, but researchers were able to confirm that the cells contain the gastric-brooding frog’s genetic material. Archer said that he is confident that the hurdles the Lararus Project team faces are “technological and not biological.”

photo via: Iamturbo.com
Even though the embryos didn’t survive, scientists say that this is a huge step in the process of bringing an animal ‘back from the dead’ and it’s simply a matter of time before it’s completely possible. Oh, and scientists being the over zealous people that they are are already planning on trying to bring back other extinct animals like the Woolly Mammoth, Dodo Bird, and Tasmanian Tiger.
Let’s not get carried away, now, folks. I’m all for bringing back these awesome creatures but don’t forget about Jurassic Park. I really don’t need Velociraptors running rampant through my backyard now.
Let’s stick to frogs that make babies in their tummies. Much safer.