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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
by aphextron 7y ago
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.
- adequateness 7y agoThat is what was thought but if the finding in the article turns out to be true then that might need to be reevaluated.
- api 7y agoThe key is half-life. A few fragments of dinosaur DNA surely remain, because half-life means there is a certain probability of decay over a particular unit of time. But enough to re-assemble a dinosaur? That's unlikely to the point of near-impossibility. Even if we got really really lucky and found some that had spent most of its existence frozen deep in Antarctica or something, that would only open the potential of restoring a single dinosaur lineage and not the vast array of species depicted in Jurassic Park. That's total fantasy.
- deleted 7y ago[deleted]
- zabeltech 7y agoWhat if the DNA was frozen?
- Baeocystin 7y agoAt these time scales, background radiation is the fundamental killer, and it is omnipresent in the environment. Using numbers taken from http://news.mit.edu/1994/safe-0105 http://news.mit.edu/1994/safe-0105 for napkin-math: Average background dose/year: 500 millirem LD50 instantaneous exposure: 450000 millirem LD100 instantaneous exposure: 600000 millirem Radiation exposure of our dinoDNA sample: 65 million * 500 = 32.5 billion millirem. Obviously there's a lot more to it than simple dose adding, but this gives you an idea of just what deep-time DNA recovery is up against.
- brobinson 7y agoRight, but even a small amount of water (and presumably, ice) is amazing at absorbing radiation. Wouldn't something buried in a few meters of ice or more be effectively insulated from radiation?
- Baeocystin 7y agoDNA isn't isotope free. Like hyperbovine mentioned, there are actually other effects that come in to play far sooner, but radiation puts (an additional) hard cap on things, and is easy to napkin-math.
- hyperbovine 7y agoAt least on the ancient DNA projects I've worked on, the main obstacles have been a) deamination, b) fragmentation, and c) environmental contamination. Maybe radiation enters the picture at Jurassic timescales, but the DNA would become completely degraded and worthless tens millions of years before that. Unless they somehow managed to find a dinosaur frozen at about 0K, I'm extremely skeptical of these claims.
- multiplegeorges 7y agoYou say this as an absolute, but this very article is describing a case where it might have been found. It's unlikely, we'll see.
- rurban 7y agoExtremely unlikely that the DNA they found is really that old. More like some recent dirt DNA. And they tried really hard to get something out of the really good Mammoth DNA from Siberia. The blood was still liquid. No chance so far.
- jhayward 7y ago> all dinosaur DNA has been destroyed for millions of years .. Except for the DNA that has survived and been passed down to living species today.
- TuringNYC 7y ago>> DNA has a half life of ~500 years. Could you describe half life here? So suppose the strands are now small snippets. If you find enough, couldnt you overlap common parts and eventually re-construct the full length?
- empath75 7y agoIt means half of the dna is destroyed every 500 years. After 65,000,000 years, you have 1/(2^130,000)th of the original DNA left, which is to say, none at all.
- varenc 7y agoDNA half-life isn't an immutable property of the material like radioactive half-life is. The environment has an effect. The DNA in cryogenically preserved tissue should have a much longer half life.
- TuringNYC 7y agoCurious what the half life would be for dinosaur blood within Amber (per the book)?
- mkl 7y agoIt seems to depend mostly on temperature and moisture: dry, cold, and unchanging are best. We have good DNA from Deniovans because it was recovered from bones and teeth that sat buried in a cave in Siberia for 50k years. Being in amber might protect from moisture, but I think the temperature and temperature swings would still likely destroy it within thousands of years.
- BrandonM 7y agoBringing 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 into the complex interaction between a mother and her unborn child, including cytoplasm, mitochondrial RNA, etc. It's not like an organism springs whole cloth from DNA alone.
- dumbfoundded 7y agoSo the culture issue you raise definitely presents some unrecoverable aspect, but as for the biology, there's certainly a path. We have animals now that are closely enough related to extinct animals that we could conceivably bring them back through incremental genetic modifications. For example, if we wanted to bring back Direwolves, we could edit the DNA of a gray wolf maximally such that it can still be fertile and be born by a non-edited gray wolf. This would give you a wolf closer to a Direwolf and then you could repeat this process using each previous generation as the carrying mother for the genetically modified embryo.
- nck4222 7y agoThis is explored in the book Jurassic Park, but was left out of the movie.
- dmurray 7y ago> Even with perfect DNA, I think we underestimate the role that social structure and ecological momentum play in even the simplest of creatures. I don't think that's true. We raise animals without their parents all the time, both on farms and in zoos. The animals we end up with are still recognizably horses or rats or chimpanzees, with unique behavioural traits that could be studied for years. Even if you lose the social structure of mammoth society, you would still be bringing back something fascinating. Animals that can be hatched from eggs have even less dependency on their mothers, too.
- 7y ago
- fenwick67 7y agoWhat about mammoths or passenger pigeons, then?
- joyj2nd 7y agoMuch easier since you can slowly morph an elephant or pidgin into a mammoth or passenger pigeon (DNA methylation etc. )
- phiresky 7y ago> DNA has a half life of ~500 years but: Researchers in 2016 measured chloroplast DNA in marine sediment cores, and found diatom DNA dating back to 1.4 million years.[62] This DNA had a half-life significantly longer than previous research, of up to 15,000 years. Kirkpatrick's team also found that DNA only decayed along a half-life rate until about 100 thousand years, at which point it followed a slower, power-law decay rate. https://en.wikipedia.org/wiki/Ancient_DNA#Non-human_aDNA https://en.wikipedia.org/wiki/Ancient_DNA#Non-human_aDNA
- hyperbovine 7y ago> and found diatom DNA dating back to 1.4 million years. Okay, so you're 1/45th of the way there.
- grecy 7y agoAlright, let's just pretend the DNA was somehow snap frozen or preserved to make it still useable. With today's technology could we create a creature from long ago with nothing more than it's DNA?
- Retric 7y agoIt would be a reasonable thing to attempt with today’s technology, but it would be a serious R&D project. It’s harder the older the sample and vastly more difficult if few closely related species survive.
- thaumasiotes 7y ago> It would be a reasonable thing to attempt with today’s technology, but it would be a serious R&D project. Dinosaurs have enough cultural prestige that it would make total sense to do it as a vanity project if the technology is there. Similar to turning lead into gold -- there's enough cultural meaning built up around it that someone should do it before it really makes sense in a vacuum.
- stanfordkid 7y agoA project like this could be the space race of our epoch!
- masonic 7y agoI could see Elon Musk funding a Jurassic Park kind of effort to re-create dinosaurs... just to be the first to taste a dinosaur-egg omelette.
- credit_guy 7y ago> 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 life of a human settlement is, let's say 50 years. That means we should see absolutely no traces of human settlements older than 2000 years (40 half-lives). That is far from true.
- londons_explore 7y agoI 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...
- andbberger 7y agoThermodynamics do not set any such bounds, but equilibrium statistical mechanics does describe temperature-dependent state transitions.
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