How long would it take to give birds their saurian appearance back through directed evolution?

Directed evolution?

@Darth_Algar
Yes.

Like what? Altering genes in the embryonic stage? Selective breeding?

Short of cloning the DNA of ancient birds from a mosquito suspended in amber, I don’t think it would be possible, as there are no saurian-type birds left alive. Just be careful what you wish for.

@Darth_Algar
Selective breeding.
@downtide
Birds still have all the genes required to express ‘lost’ saurian traits, they are just deactivated.

@downtide As far as I recall the theoretical usable life of DNA is, at best, around 1,000,000 years. Long after the emergence of birds on the evolutionary scene. So there won’t be any cloning of dinosaurs or of saurian ancestors of birds from preserved mosquitos.

@ragingloli I really don’t see how it would be even hypothetically possible to “reverse engineer” evolution through breeding, but perhaps someone more knowledgeable that I would know.

@Darth_Algar I mean in theory it would just be selective breeding through animals that express whatever genes you’re looking for. I don’t know enough about birds to say with any level of knowledge how long something like this would take, but I don’t see why it’s not possible. It’s not like we don’t already do this with other animals.(look at all the breeds of dog we’ve created.)

@uberbatman The differences in dogs breeds are like the differences in human “races”. It’s only superficial, surface level stuff. They aren’t different species, nor are there any real physiological differences. What TC proposes sounds less like creating a different breed of dog and more like, say, trying to reverse Homo sapiens to Australopithecus.

There has been some discussion of how it might be possible to get a wooly mammoth by reworking the DNA of a modern Asian elephant. That would be possible only because we have the complete DNA of the mammoth, so we would know where modification needs to be made.

The bird-to-dino scenario could work the same way except that we don’t have a dino genome to work from.

I would start with some cassawaries. They already look like monsters, with huge feet and that big spine on top of their heads.

@thorninmud
Well, it does not have to be a complete genetic match, it just has to look like one.

Probably depends which bird you start with. If a cassowary, maybe not long at all. Don’t forget that it’s looking like a lot of dinosaurs that we picture as being lizard-like already had the beginnings of feathers.

I recently saw an article on the internet with photographs comparing the difference between dog breeds of the 1930’s and those of today. Some were pretty significant differences.

If they could achieve that in 80 years I would not be surprised if you could do it in a century considering that you would be starting with a much greater degree of knowledge we now.

I think the biggest issue would be breeding rate. Dogs have several babies at a time, quickly, and will mate with anything. Many types of birds are much more selective, and are monogamous, so you won’t be able to inbreed for traits as easily.

My first thought would be that chickens would be an easy species to selectively breed – turns out, it’s already being done

If we allow intentional, educated DNA modifications it might not take as long as you think. It only took one generation to genetically modify mice, rabbits and cats so they fluoresce like jellyfish.
It only took a couple of generations to genetically engineer turkeys with breasts so large they can’t stand up.
Give a GM company the desired DNA and the economic incentive, and they will surprise you.
Just think how cool it would be to have glow-in-the-dark reproductive organs! Way better than boring ink tattoos. If the demand and the price were high enough Ceres and Monsanto would be working on it as we speak.

I think teeth would take a long time. It would be hard to select for it, because it would be impossible to tell on phenotype what a proto tooth looks like. Most of it would be sloshing back and forth between more tooth like and less tooth like.
I suppose you could try to find some birds that don’t lose their egg tooth, and breed them…

I would work on Grackles. Have you noticed the way they eye you from the roof of the car? Kind of like you are a food item. There is most definitely saurian temperament behind those eyes.

… Or! You could lock some birds up, feed them a diet where teeth would be an asset (but not a requirement), then let only the biggest birds breed…

@drhat77
In the case of teeth it is just a matter of switching the respective genes on.
Then breed for teeth size.

Selective breeding doesn’t suffice. We’d have to recreate the climate, the food chain and other environmental factors. Genetic engineering is the only chance, but this requires more knowledge about the semantics of vertebrate genomes, in particular the ones of birds, not just sequencing and deducing the syntax.

It has recently come to my attention that modern birds are direct descendants of small theropods. So we’re not going to be able to get an Apatosaurus-like creature in a reasonable time no matter how far we encourage the bloodline.

Who knew I’d learn so much homeschooling a five year old?