Conical teeth in a Talpid mutant. Credit: Current Biology
Normal chick on the left, the talpid2 is on the right. The mutant jaw clearly shows teeth. Credit: John F. Fallon and Matthew P. Harris
Posted on 02/23/2006 6:41:48 AM PST by GreenFreeper
Chicken will grow teeth when pigs can fly.
Well, better start searching the skies for flying pork—scientists have discovered a mutant chicken with a full set of crocodile-like chompers.
The mutant chick, called Talpid, also had severe limb defects and died before hatching. It was discovered 50 years ago, but no one had ever examined its mouth until now.
The researchers recently created more Talpids by tweaking the genes of normal chickens to grow teeth.
"What we discovered were teeth similar to those of crocodiles—not surprising as birds are the closest living relatives of the reptile," said Mark Ferguson of the University of Manchester.
What happened
Around 300 million years ago, the ancestor of all modern vertebrates gave rise to two lineages, the mammals and the reptiles/birds. The oldest reptiles, such as crocodiles and alligators, had cone-shaped teeth. So did the earliest birds, called archosaurs.
Then, around 80 million years ago, modern birds emerged without teeth.
"So what would you expect bird teeth to look like? You would expect them to have teeth like their ancestors and their most closely related living relative," study co-author John Fallon of the University of Wisconsin told LiveScience.
Indeed, Talpid's teeth are conical, much like an archosaur's and closely resembling the teeth of a baby alligator or crocodile, Fallon said. If the chick survived, the teeth would most likely reabsorb into the mouth.
The archosaurs had mouths similar in shape to a reptile's. It turns out that developing a beak caused birds to lose their teeth.
"The reason that birds lost their teeth is that in forming a beak, the two tissues that ‘talk' to each other to make a tooth become separated," Fallon said. "They can't have the conversation to make a tooth. In the mutant, these tissues are brought back together."
Make more mutants
The finding made scientists curious whether healthy chickens still possessed the 80-million-year-old genetic pathway for producing teeth.
By making a few changes to the expression of certain molecules in the pathway, the researchers were able to induce tooth growth in normal developing chickens. These teeth also looked like reptilian teeth and shared many of the same genetic traits, supporting the scientists' hypothesis. None of these chickens were allowed to hatch.
This is all good news for hockey players. A direct application of this research, Ferguson said, could be re-growing teeth in people who have lost them through accident or disease.
The research is detailed this week in the journal Current Biology
Conical teeth in a Talpid mutant. Credit: Current Biology
Normal chick on the left, the talpid2 is on the right. The mutant jaw clearly shows teeth. Credit: John F. Fallon and Matthew P. Harris
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Exqueeze me...but pointy beak ridges are not teeth.
Where are the roots? The Enamel, etc...
Yeah, but I hear they're pretty scarce.
We can expect the Sci-fi soon; Day of The Talpid. Featuring flocks of man eating chickens and a crowd surrounded and trapped at the local KFC.
Toof Ping
Chicken Train....
I'd like them to take a secretary bird ebyro, get it to grow teeth, than implant hoatzin bird genes to get it to grow wing claws and VOILA! Instant velociraptor!
"Conical teeth," my Aunt Harriet's butt! My niece did that watercolor when she was 6. She said it was a bunny wabbit. We taped it to the refrigerator.
No one yet has mustered a reply that references hen's teeth?
Work with me, people!
It's interesting, but what good are teeth if you eat nothing, but corn! I mean they never needed teeth before. Well I guess chickens need all the help they can get. they need to look like a Croc so they can swim to the nest and snatch up all the baby Crocs!!!! ARGGGGG.... I'm a little crazy.
so how did the gizzard develop?
http://en.wikipedia.org/wiki/Gizzard
Maybe the are arming up for a revolt against the human oppressors.
Interesting.
I do not know for certain how they developed but I know several herbivorous dinosaurs were thought to have rudimentary gizzards. The evolution of a gizzard eliminated the need for sharp teeth and thus were lost. Birds are thought to be descended from herb. dinos so this makes quite a bit of sense to me.
But that doesn't answer the age-old question: "Do chickens have lips?"
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