What Came First: The Chicken or the Dinosaur?
A Look at Reverse Evolution.
A Look at Reverse Evolution.
Napoleon Dynamite: Do the chickens have large talons?
Farmer: Do they have what?
Napoleon Dynamite: Large talons.
Farmer: I don't understand a word you just said.
Actually, one day they might, along with teeth, claws, scales and long reptilian tails. Well, then they wouldn’t be chickens anymore, they would be dinosaurs!
If dinosaurs are the ancestors of chickens, could genetic engineers turn the clock back on chicken DNA and recreate a dinosaur? A Canadian researcher thinks it's possible, and has begun experiments to do just that.
Montreal's McGill University has claimed they will attempt to reverse-engineer a dinosaur from a chicken by altering chicken genes that have evolved since the Cretaceous. Their quest to build a dinosaur is taking them millions of years into the past, and forward again to the cutting edge of science technology. If all goes according to plan, we will have dinosaurs within five years’ time.
“Reverse evolution” has been successfully performed in mice and flies, but those experiments were re-introducing just a few bygone traits. The dinochicken project instead has the goal of bringing back multiple dinosaur characteristics, such as a tail, teeth and forearms, by changing the levels of proteins that have evolved to suppress these traits in birds. The only reason there using chickens, instead of some other bird, is that the chicken genome has been mapped, and chickens have already been thoroughly studied.
McGill University paleontologist Hans Larsson is working to make it happen. Larsson is experimenting with chicken embryos to create the creature he describes: a “chickenosaurus,” they call it. If he succeeds, Larsson will have made an animal with clawed hands, teeth, a long, dinosaurian tail and ancestral feathers.
Three years ago, evolutionary biologist Neil Shubin found one of the biggest fossil finds of the century: Tiktaalik, a 375-million-year-old fish with a neck, elbows, shoulders, and wrists. An almost perfect link between fish and land vertebrates, Tiktaalik (unearthed in Nunavut) is our own distant cousin. Just as Larsson looks to dinosaur bones to understand his embryos, Shubin used the fossil to design an experiment with modern-day paddlefish. He found that, even before limbed animals evolved about 365 million years ago, fish had the genes necessary to grow arms and legs. “Evolution doesn’t always rely on the development of new genes,” Shubin explains. “It’s redeploying old genes in new ways: changing their switches, or their time of activity.” By using the right genetic switches at the right time, then, Larsson should be able to build a dinosaur inside a chicken egg.
What they have accomplished so far is a chicken embryo, less than half as big as your thumb, the specimen is almost unrecognizable, and not just because of its sharp hands and feet, or its two wide, empty eyes. The embryo’s delicate spine continues well past its backside, creating a thick and pointed tail. Fully developed chickens, of course, don’t have tails.
As we know, an embryo develops from just a few cells into a fully formed creature. The chicken embryo sprouts five fingers with clawlike tips, a hint of teeth, and a tail (up to 22 vertebrae, roughly 15 more than in a developed chicken). Suddenly, a genetic switch flips: the teeth disappear, the tail is destroyed, and the five fingers become three. It looks much more like a bird. Why would an embryo build extra fingers, teeth or a tail, only to have them disintegrate? Evolutionary change is like tuning a car while the engine’s running,. You can’t just junk one part and put something else in; in the meantime, it wouldn’t work. Those pre-existing programs are often the foundation for something new. The trick is to override them.
He has no doubt that within five years we will have dinosaur-like creatures running around in enclosures, and after that they will experiment with larger specimens, such as making a dinosaur out of an emu. Does this sound like a terrible Jurassic Park mistake, because the humans lost in that movie, then again the dinos are predicted to be a bit larger than an average chicken, not exactly a killing machine like the velociraptor or T-rex. According to Larsson, there is no danger of the proposed dinochicken escaping and populating the world with dinosaurs, since only the chicken’s development, and not its genome, would have been affected. If the creature did somehow escape and could mate, the result would just be a regular chicken. No fear of Jurassic Park 4 I guess.
Good luck to the team at McGill University and I look forward to the completion of their project, it will be a huge leap forward in bioengineering science.
Sources
Stefano,
ReplyDeleteYour blog was very interesting. Your choice of topic was fascinating. I never knew that reverse evolution was possible. I think that this is a positive advance in science and it will allow scientists to more closely study and learn about extinct animals and will allow us to help better understand our world. I also like how you mentioned that we are only changing its development and not its genome so it will not tamper with the natural state of ather creatures by reproducing another species. I feel this will be best for the environment. I would really like to see dinosaurs in the next five years, that would be an amazing breakthrough. Good luck to the team at McGill!
Annie :)
STEFANO!!!!!!
ReplyDeleteGood job on your blog! it was a very intetesting topic! Although I would be kind of freaked out to know that I could possibly see a dinosaur on earth in the next five years. I found it interesting that when a chicken embryo first forms it has five claw-like fingers, teeth, and a tail but later on in the process all those things disappear...What? One thing I Must say is that all this seems a little unrealistic to me. I would love to see that McGill team prove me wrong though! Really good job anyway!
D:)