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What would it take to bring back the dinosaurs?

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Re: What would it take to bring back the dinosaurs?

#131

Post by worldsayshi »

ben_w wrote: post #70
chasil wrote: post #38

Earlier quoted context omitted.

As far as I understand, keeping such creatures alive would require facilities with enriched oxygen. If the large ones escaped, they would suffocate. "...large dinosaurs really required to be living in an oxygen tent. An atmosphere in the neighborhood of 35 percent oxygen would be considerably more compatible with large dinosaurs than one in the neighborhood of 28." Volcanic activity in the Cretaceous enabled these hi…

Hmm… I have a question inspired by your choice of phrases: Is there a graph somewhere of Earth's mean sea level atmospheric pressure over time? Was it significantly different e.g. a billion years ago?

This doesn't directly answer your question but adds some interesting context. Some dinosaurs shouldn't be able to fly in the current atmosphere:

https://lru.praxis.dk/Lru/microsites/hvadermatematik/hem1dow...

Re: What would it take to bring back the dinosaurs?

#132

Post by melagonster »

namrog84 wrote: post #96
hvs wrote: post #78

Earlier quoted context omitted.

It seems like more than an issue of DNA to create a 50 ton dinosaur that could survive in a modern climate. Dinosaurs were able to reach their sizes precisely because of the oxygen-rich environment, not just their DNA.

So we make small dinosaurs? What about not bringing back dinosaurs but changing the dna of say a chicken to resemble that what we'd consider to be a dinosaur without it actually being any historically known dinosaur?

this sounds like the way, actually this is how it work in book. I think this will happen.

Re: What would it take to bring back the dinosaurs?

#133

Post by aflag »

_moof wrote: post #128
aflag wrote: post #110

Earlier quoted context omitted.

Why would 30% oxygen be hard to deal for humans? I didn't think a greater oxygen concentration really mattered to us.

Here you go: https://en.wikipedia.org/wiki/Oxygen_toxicity

Interesting. I always assumed divers had 100% oxygen tanks, but I guess percentage and pressure are different things. But with that in mind, wouldn't a great percent of oxygen just mean there is less of the other gases, but the relative pressure would still be the same as gravity didn't change?

Re: What would it take to bring back the dinosaurs?

#134

Post by _moof »

aflag wrote: post #133
_moof wrote: post #128

Earlier quoted context omitted.

Here you go: https://en.wikipedia.org/wiki/Oxygen_toxicity

Interesting. I always assumed divers had 100% oxygen tanks, but I guess percentage and pressure are different things. But with that in mind, wouldn't a great percent of oxygen just mean there is less of the other gases, but the relative pressure would still be the same as gravity didn't change?

When you're dealing with one constituent of a gas mixture, it's partial pressure that counts, not the pressure of the whole mixture. If the proportion of oxygen in the atmosphere were to increase without a change in overall atmospheric pressure, the partial pressure of oxygen would increase. Another way of saying this is, you would have more oxygen molecules in the same volume of space. The total number of all molecules per unit of volume would be the same, but more of those molecules would be oxygen. More oxygen molecules per unit of volume = higher pressure.

Re: What would it take to bring back the dinosaurs?

#135

Post by BurningFrog »

thaumasiotes wrote: post #117
BurningFrog wrote: post #111

Earlier quoted context omitted.

Well, maybe, but humans can live at altitudes with about to half our normal oxygen levels, so maybe dinosaurs would have similar tolerances.

Humans tolerate those altitudes very poorly. They suffer from health problems and miscarriages. High-altitude genetic adaptations have been the subject of a fair amount of study; there are three major groups bearing such adapations: Tibetans, Ethiopians, and Andeans. The Andean adaptation suite is noticeably more primitive and lower-quality; this is generally thought to be the result of having evolved only very recen…

Thanks. I didn't know Ethiopians were also in the altitude mutant club!

My anecdote is I travelled in Bolivia for 3 weeks. Never under 3700 meters. One day we climbed Uturunku (6008 meters) as part of a jeep tour, You start at 5100 meters, so it's less crazy than it sounds.

Of the 6 tourists starting, only 3 made it up, with some real struggles.

Meanwhile, our native guide seemed to just have a relaxing walk...

Re: What would it take to bring back the dinosaurs?

#136

Post by UltraViolence »

I always have one simple adage that I recite: eternity is a long time.

We can't know what will be in the realm of possibilities in 100 years, let alone 1000 years or tens of thousands of years.

It wouldn't surprise me in the slightest if we'd be able to recreate dinosaurs in a couple hundred years. And whether it's a good thing isn't really the issue. If Man can do something, he will.

The only thing I'm pretty sure about is that it won't be in our lifetimes. Unless we conquer aging and death that is.

Re: What would it take to bring back the dinosaurs?

#137

Post by martinflack »

Geee wrote: post #97

In the future we can simulate growth and metabolism of a specimen, when we have its DNA. So we'll at least have a biologically accurate simulated Jurassic Park. That's also when we can debug consciousness, given that our simulation is accurate enough. I have no idea how many years we'll have to wait. Maybe 50 years?

That was my thought as well. With sufficiently advanced computing and world modeling, we wouldn't use DNA to bring back real creatures, just high-fidelity digital ones, complete with a simulated environment that suits them.

Re: What would it take to bring back the dinosaurs?

#138

Post by jameshart »

worldsayshi wrote: post #131
ben_w wrote: post #70

Earlier quoted context omitted.

Hmm… I have a question inspired by your choice of phrases: Is there a graph somewhere of Earth's mean sea level atmospheric pressure over time? Was it significantly different e.g. a billion years ago?

This doesn't directly answer your question but adds some interesting context. Some dinosaurs shouldn't be able to fly in the current atmosphere: https://lru.praxis.dk/Lru/microsites/hvadermatematik/hem1dow...

Luckily they evolved feathers and manage just fine.

Re: What would it take to bring back the dinosaurs?

#139

Post by jameshart »

csomar wrote: post #121
davidw wrote: post #99

Earlier quoted context omitted.

They had millions of years to evolve.

So did many other organisms who are still with us today. I'm guessing most organisms will be fine if the basics are covered (tolerable level of oxygen and air pressure, tolerable levels of radiations).

Evolution doesn’t work by having individual creatures keep calm and carry on just ‘putting up’ with whatever geological, climatic or atmospheric changes take place.

Evolution works by having creatures that can’t handle the new situation die. Preferably before they are able to reproduce.

And it may have escaped your attention, but the large non-avian dinosaurs? They all died out.

Re: What would it take to bring back the dinosaurs?

#140

Post by jameshart »

Archelaos wrote: post #33
photochemsyn wrote: post #13

Dinosaurs are gone, all that remains is their bone structures. No complete genomes are recoverable, just maybe a few fragments. However if you want dinosaur-like creatures, you're basically talking giant flightless birds. So, start with something like an ostritch or a rhea, and use CRISPR to make selective edits aimed at increasing leg size and bone density. This would require a comprehensive understanding of develop…

Complete layman here. -- What about trying to reconstruct a likely common ancestor of reptiles and birds on the DNA level and combining this with the Parent's approach?

The ‘common ancestor of reptiles and birds’ is way older than dinosaurs. And it’s also the common ancestor of all mammals.

You could get the common ancestor of birds, dinosaurs, and a living reptile if you just go to the common ancestor of, say, a chicken and a crocodile. That’s also the ancestor of pterosaurs as well as dinosaurs though.

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