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Possible dinosaur DNA has been found

scientificamerican.com

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Re: Possible dinosaur DNA has been found

#61

Post by londons_explore »

BrandonM wrote: post #28
aphextron wrote: post #8

Earlier quoted context omitted.

It's a completely impossible fantasy. DNA has a half life of ~500 years. Mammoths only died out around 10,000 years ago, which is why it's conceivable that one could be brought back, but all dinosaur DNA has been destroyed for millions of years.

Bringing back mammoths based only on DNA seems to me to be akin to bringing back a New Yorker based only on DNA, thousands of years after NYC no longer exists. Even with perfect DNA, I think we underestimate the role that social structure and ecological momentum play in even the simplest of creatures. I think humans are the rule and not the exception when it comes to learning after birth. And that's not even getting…

What you say might be true, but it might not matter.

If you were to clone a New Yorker thousands of years from now and put them in an exhibit in a Zoo marked "New Yorker", lots of people would be very impressed, even if they didn't start cooking New York-style pizza.

Re: Possible dinosaur DNA has been found

#62

Post by joyj2nd »

koeng wrote: post #41
syntaxing wrote: post #3

This is a naive question...but let's just say we do have the DNA, is Jurrasic park possible with today's technology?! I remember reading that someone was trying to inseminate an elephant with mammoth sperm a couple years ago but failed. Not sure if it was because the sample was super old or it just doesn't work.

Possible? Yes. Practical? Not for 2-3 decades when DNA synthesis capacity gets good enough to synthesize full animal genomes. In terms of raw synthesis power, we do have the ability to synthesize billions of base pairs, but you're going to need other infrastructure around it. Also, immune problems I don't think would be a huge issue, the adaptive immune system has been around for a while.

" we do have the ability to synthesize billions of base pairs" This is a valid point. We don't have the technology yet. There was once an SBIR opening for long DNA synthesis but I did not keep track of it. But, given we have the technology it still would not be enough. To slowly make an elephant a mammoth. Yes. Maybe. But making a Tyrannosaurus Rex from scratch is tricky, you also need cells, mitochondria, DNA methylation etc.

Re: Possible dinosaur DNA has been found

#63

Post by joyj2nd »

fenwick67 wrote: post #29
aphextron wrote: post #8

Earlier quoted context omitted.

It's a completely impossible fantasy. DNA has a half life of ~500 years. Mammoths only died out around 10,000 years ago, which is why it's conceivable that one could be brought back, but all dinosaur DNA has been destroyed for millions of years.

What about mammoths or passenger pigeons, then?

Much easier since you can slowly morph an elephant or pidgin into a mammoth or passenger pigeon (DNA methylation etc. )

Re: Possible dinosaur DNA has been found

#64

Post by londons_explore »

neilwilson wrote: post #21
syntaxing wrote: post #3

This is a naive question...but let's just say we do have the DNA, is Jurrasic park possible with today's technology?! I remember reading that someone was trying to inseminate an elephant with mammoth sperm a couple years ago but failed. Not sure if it was because the sample was super old or it just doesn't work.

It would die near instantly anyway. Very likely modern bacteria and viruses would overwhelm the creature's immune systems.

The same argument could apply when you take plants or animals from one continent to another when those continents haven't been connected for tens of millions of years.

Yet somehow camels or kangaroos seem to have no trouble living in each others environments.

In fact, you see a bit of the reverse - Banana skin rapidly decomposes in tropical forests where bananas grow, but take one to frigid Norway and drop a banana skin in a forest and you'll still be able to find it in 5 years, while local stuff is decomposing around it.

Re: Possible dinosaur DNA has been found

#65

Post by joering2 »

roywiggins wrote: post #10

"At best, their biological makers seem to be degraded remnants of genes that cannot be read—broken-down components rather than intact parts of a sequence." So... what good does that do?

Well, some of that stuff can be replaced with other animals DNA, like frogs /j

Re: Possible dinosaur DNA has been found

#67

Post by londons_explore »

credit_guy wrote: post #46
aphextron wrote: post #8

Earlier quoted context omitted.

It's a completely impossible fantasy. DNA has a half life of ~500 years. Mammoths only died out around 10,000 years ago, which is why it's conceivable that one could be brought back, but all dinosaur DNA has been destroyed for millions of years.

> DNA has a half life of ~500 years DNA is not a radioactive material. It decays, but there's no absolute law like the radioactive decay, where the half life is the same for every microgram of the same substance everywhere in the world. The average half-life may be 500 years, but there can be situations where the DNA is exceptionally well preserved due to local circumstances. As a simple analogy: the average half lif…

I believe the laws of thermodynamics do set bounds on the breakdown rate of molecules at a specific temperature...

No molecule is 100% stable... Every molecular bond will break eventually due to random thermal noise...

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