Comment by subsubzero | Hacker News Reader

Comment by subsubzero | Hacker News Reader

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I love thought experiments like these, One would have to think where could ancient dinosaur DNA survive? Antarctica has been covered by ice for 5 million years, that is still 60 million years too young. Maybe there are a few bugs that have dino dna that is better preserved than the stuff that has been exposed to sunlight and elements the past 5 million years. And even if there is viable dna you would have to drill down 13-15k feet of solid ice to the antarctic landmass, which might as well be impossible(if you knew exactly where to look).

And lets say you bring the dinosaurs back, what was the air and temperature like for them? back >65mya earth had 30% oxygen(its 21% today) that much oxygen would be hard to deal with for humans today(cuts would heal in a day though!), also forest fires would be uncontrollably bad. And what about the temperature? It would be 10 degrees warmer than it is today. So you would have to alter the climate and atmosphere significantly for your newly cloned dinosaurs to survive, or perhaps they could adapt to our current conditions, who can say?

If you want to make a really dramatic movie, have it survive in giant rock fragments knocked into orbit around the sun when the Chicxulub meteor struck the Earth. The inside would hopefully remain very cold and shielded from external radation.

I suspect though that not only would breakdown of DNA still happen on it's own, but atomic decay within the rock would be enough to destroy the DNA.

Lets not also forget cosmic rays and their effect on interstellar debris(astronauts helmets showed micro holes caused by these rays under an electron microscope) :)

My interest was piqued when you mentioned cuts would heal faster. Is there a video that explains what life would be like if the earth had higher concentrations of oxygen? (30,50,70)?

On mobile, will let someone else search. But what springs to mind : more O2 means faster reactions, so faster metabolisms, so bigger animals and more cancer. Though the latter only compared to equally sized animals today (bigger animals tend to have lower cancer rates I think?)

Co2 levels were 5x or 10x higher back then as well, so large forest fires weren’t likely.

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?

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.

Only one way to find out!

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