Is The "chickenosaurus" Project Actually Possible?

[Carcharodontosaurus]

I've been wondering about Jack Horner's "Chickenosaurus" project, and am questioning if it is actually possible. He has been talking about it since around 2009, and although he has brought up the idea a lot, there doesn't seem to be any reported progress. For those who don't know, he is planning to make a dinosaur-like creature (technically already a theropod dinosaur, but an avian one) by turning certain genes in a chicken embryo on and off, creating a chicken with a long tail, hands and teeth.

So is this actually possible? I know some scientists at Harvard are looking at which genes are shared between chickens and alligators and turning them on and off to see their expression, but unlike Horner they are not planning to create a living creature out of it.

Before you say it, I don't want to hear about this project being useless or unethical. I only want to know if it is actually possible.

[Malcolmt]

I read his book "How To Build a Dinosaur" on the subject (excellent book)and he is not really going to recreate an extinct dinosaur. He is talking about turning on genes that are already there but currently dormant. It has long been known that chicken are occasionally born with teeth or a tail when a dormant gene is randomly switched on.

I suspect it is quite probable that someone will figure out how to do this. Seems much more likely than trying to go the Jurassic Park route and put recreated dinosaur DNA into a current creatures germ cell.

Regardless it will not be a dinosaur, it will be a modern animal with dormant genes switched on....

[cowsharks]

I highly doubt that mankind will ever posses the knowledge to do what you describe. A few years ago I heard an excellent talk at a fossil club meeting by a medical doctor well versed in DNA research, and his talk was on the theory of taking DNA material from one of the Mammoth's from Siberia and inserting into the DNA of a modern elephant to get a hybrid or something. Basically, the research is light-years away from figuring out how to do this.

[Carcharodontosaurus]

I read his book "How To Build a Dinosaur" on the subject (excellent book)and he is not really going to recreate an extinct dinosaur. He is talking about turning on genes that are already there but currently dormant. It has long been known that chicken are occasionally born with teeth or a tail when a dormant gene is randomly switched on.

I suspect it is quite probable that someone will figure out how to do this. Seems much more likely than trying to go the Jurassic Park route and put recreated dinosaur DNA into a current creatures germ cell.

Regardless it will not be a dinosaur, it will be a modern animal with dormant genes switched on....

Chickens are already dinosaurs though, so it will be a dinosaur, just not an extinct species. For me, a chicken with a long, bony tail and hands with claws is enough.

Edited March 4, 2014 by Carcharodontosaurus

[Mediospirifer]

Switching genes off or inserting additional ones is possible, although difficult. There are breeding lines of lab mice with specific genes knocked out for studying genetic diseases, for instance. How this would aply to chickens, I don't know, but it seems like it should be possible.

It's an interesting puzzle!

[Boesse]

Seconding Carcharodontosaurus' comment. Chickens - and all other birds - are already dinosaurs.

That being said, keep in mind that atavistic teeth, tail development, and atavistic claws have already all been documented in juvenile birds - either occuring naturally, or by switching genes off (e.g. tail development). Jack's proposal is simple: do all three in one specimen, and you have a modern dinosaur with nonavian dinosaur traits - already present (but suppressed) in its DNA - and let it hatch. Currently it's illegal to let it hatch in most countries, so that's one issue - but give it a few years, and once all the specific genes are located in the genome, it is totally possible.

Mediospirifer - knockout mice - er, knockout chickens - is exactly how these individual genes (turned off for tens of millions of years) were located in the avian genome.

[Mediospirifer]

Interesting!

I didn't know that those specific atavisms had been observed (excepting clawed wings in quetzal birds), let alone any of the genes responsible located. I have read Gould's essay about "Hen's Teeth and Horses' Toes", but that experiment was rather different than knocking out genes.

One thing is certain: if there's a place where it can be done legally, someone will likely try it! The results will be very interesting.

[Auspex]

I think Horner's idea is an interesting thought experiment. Who can say what fruit it may or may not bear in the unseen future?

The ethics will need to be addressed even if the technology advances to where it might be achievable.

[jpc]

A couple comments... it is not the quetzal, but the hoatzin that has claws on its hands as a youthful bird. Daryl, the stuff with DNA in frozen mammoths is completely different form what Horner et al are doing. That is Jurassic Park technology and is likely well in the future if at all. I did a quick search on Hans Larsson at McGill University... he is one of Jack's colleagues on this, but his McGill site only lists what he is working on.. no details. Maybe there is more results of this project out therbut I gotta get back to work.

[Carcharodontosaurus]

A problem with the tooth thing is that birds no longer have functional genes for enamel, only an enamelin pseudogene.

[Mediospirifer]

A problem with the tooth thing is that birds no longer have functional genes for enamel, only an enamelin pseudogene.

Going back to the Gould essay I mentioned above (Hen's Teeth and Horses' Toes), the researchers combined epithelial tissue from a five-day-old chick embryo with mesenchyme from sixteen to eighteen-day-old mouse embryos. Out of 55 grafts, ten produced dentin, and four produced complete teeth. Gould explains that the mesenchyme makes dentin in the presence of epithelium, then the epithelium makes enamel in the presence of dentin. Chicken mesenchyme is no longer capable of making dentin, although given the presence of dentin, their epithelium can still make enamel.

But that was tissue grafting, not genetic manipulation. Rather different from what is described here, and not a heritable trait.

The research that Gould cites was reported Feb. 29, 1980 by E. J. Kollar and C. Fisher. He doesn't give a full citation beyond that.

Evo-devo is fascinating. I have to wonder what other morphological changes would go with the growth of teeth, tails, and wing claws!

[Auspex]

...I have to wonder what other morphological changes would go with the growth of teeth, tails, and wing claws!

That's the question that makes me nervous about the whole thing...

"Here, Dr. Schwartznagel; hold my beer, I'm going to try something!"

[Auspex]

"You've got to be very careful if you don't know where you're going, because you might not get there."

Yogi Berra

[Boesse]

That's the question that makes me nervous about the whole thing...

"Here, Dr. Schwartznagel; hold my beer, I'm going to try something!"

That's oddly dismissive, and no more applicable to this than any other scientific study. I think the researchers involved have done their homework.

[Auspex]

That's oddly dismissive, and no more applicable to this than any other scientific study. I think the researchers involved have done their homework.

I am sure the researchers are fully cognizant of the potential perils, and are exercising an abundance of caution.

After all, no one can say what the consequence of loosing a self-replicating organism into the environment might be...

[jpc]

I don't think they are looking at even getting as far as self-replicating with these chickenosauri. Make dino soup out 'em.

[Carcharodontosaurus]

I don't think they are looking at even getting as far as self-replicating with these chickenosauri. Make dino soup out 'em.

JPC is right. Jack Horner has said that if the chickenosaur was to mate with another chickenosaurus, it would produce a chicken.

[Mediospirifer]

I don't think they are looking at even getting as far as self-replicating with these chickenosauri. Make dino soup out 'em.

It'll just taste like chicken!

[Mediospirifer]

JPC is right. Jack Horner has said that if the chickenosaur was to mate with another chickenosaurus, it would produce a chicken.

So the genetic changes aren't heritable? They must be planning to alter the DNA expression after the embryos have differentiated then, rather than engineering a zygote.

This does reduce the potential hazard of having a breeding population escape from the lab!

I'm still wondering what other morphological changes would be likely. With the growth of teeth, I would expect the new critter to have a more lizardlike face, not a beak, but what would it look like? What would the teeth look like? I'd think the critter would be more insectivorous than anything else, but I certainly could be wrong. And the wings: how would their proportions change with the development of claws? Would the wing feathers follow the same pattern? Same for the tail--how would the feathers grow? Would the final critter be able to fly? Not that chickens are particularly good at flying!

I know the best answers available without trying it would come from looking at the fossil record. But there will still be surprises if the project does happen.

[Carcharodontosaurus]

So the genetic changes aren't heritable? They must be planning to alter the DNA expression after the embryos have differentiated then, rather than engineering a zygote.

This does reduce the potential hazard of having a breeding population escape from the lab!

I'm still wondering what other morphological changes would be likely. With the growth of teeth, I would expect the new critter to have a more lizardlike face, not a beak, but what would it look like? What would the teeth look like? I'd think the critter would be more insectivorous than anything else, but I certainly could be wrong. And the wings: how would their proportions change with the development of claws? Would the wing feathers follow the same pattern? Same for the tail--how would the feathers grow? Would the final critter be able to fly? Not that chickens are particularly good at flying!

I know the best answers available without trying it would come from looking at the fossil record. But there will still be surprises if the project does happen.

The growth of the teeth will depend on whether Horner would accept tissue grafting or transgenesis from other species. If not, then the teeth will basically be tiny buds. Arkhat Abzhanov has modified the beak of a chicken embryo into something more resembling an alligator snout.

[Scylla]

To answer the first question: is it possible? Yes it is. Put enough money and brains into it and it would be rather easy I expect. I'd even bet you could get one in less than a century with good old fashioned inbreeding and selection. Might be easier to convert a mouse into a reptilian looking creature just because the whole knockout/transgenic toolkit is built for mice. If it was up to me though I would do it with ostriches as a starting point.

[Carcharodontosaurus]

To answer the first question: is it possible? Yes it is. Put enough money and brains into it and it would be rather easy I expect. I'd even bet you could get one in less than a century with good old fashioned inbreeding and selection. Might be easier to convert a mouse into a reptilian looking creature just because the whole knockout/transgenic toolkit is built for mice. If it was up to me though I would do it with ostriches as a starting point.

Chickens are cheaper, though. And mice have had more time to evolve from mammal-like reptiles than birds have had to evolve from non-avian dinosaurs.

[Mediospirifer]

If it was up to me though I would do it with ostriches as a starting point.

I think I'd want to see that one from a safe distance, or the other side of a wall!

[Mediospirifer]

Chickens are cheaper, though. And mice have had more time to evolve from mammal-like reptiles than birds have had to evolve from non-avian dinosaurs.

Not to mention you wouldn't get a dinosaur analog from a mouse! It would be an older type of reptilian.

Could be interesting...

[Boesse]

I am sure the researchers are fully cognizant of the potential perils, and are exercising an abundance of caution.

After all, no one can say what the consequence of loosing a self-replicating organism into the environment might be...

As of yet I'm unaware of any plans to release these into the environment...