Ok, to clear things up, what they found was a rock, literally a rock down to the molecular level, that is perfectly shaped as a dinosaur embryo. It reveals some interesting similarities to birds and stuff and good for paleontology.
But none of this contain even a miniscule amount of meat or organic material or DNA of a dinosaur. Those already disintegrated aeons ago. DNA half life is around 500 years. After a million years, it would have degraded so bad you literally have nothing left to reconstruct no matter how much sample you discover.
If you start with an entire dinosaur, let say 10 tons, and let be generous and have 1% of that being DNA, you get 1e15 copies of the genome, assuming a 10Gb genome. After 25,000 years, you get less than 1 copy left. Now make it 25 millions years...
I know this "half-life" term is kind of a misnomer since unlike radioisotope where it is unaffected by environmental conditions, DNA "half-life" can be longer depending on things like temperature and pressure. But still, on the scale of millions of years, it becomes exceedingly improbable that we can find even 1 copy of a dinosaur genome left.
> DNA half life is around 500 years. After a million years, it would have degraded so bad you literally have nothing left to reconstruct no matter how much sample you discover.
That article with the 521 half life of DNA was complete bull. In 2022 they found DNA from a 2 million year old mastodon [1].
The whole 521 year half life is something like "it was that in our sample, and we can't guarantee that the result generalizes". Good maybe for a high school science project, not good for a paper in Nature.
The half-life of 521 years does allow for some million year old DNAs to be found. The original paper even noted this possibility in exceptionally good environments [1, section 4]:
> Our results indicate that short fragments of DNA could be present for a very long time; at –5°C, the model predicts a half-life of 158 000 years for a 30 bp mtDNA fragment in bone. Even rough estimates such as this imply that sequenceable bone DNA fragments may still be present more than 1 Myr after deposition in deep frozen environments. It therefore seems reasonable to suggest that future research may identify authentic DNA that is significantly older than the current record of approximately 450–800 kyr from Greenlandic ice cores.
Anyone knows what research came out after scientists recovered 70 million-year-old T. rex soft tissue back in 2005 ? I remembered being blown away by the fact we could have soft tissues instead of fossilized remains... https://www.nbcnews.com/id/wbna7285683
Thanks! So not only preservation of soft tissue was confirmed, although the exact mechanism is not fully understood. But also there are "multiple lines of evidence for material consistent with DNA in dinosaur" found in fossils https://www.sciencedirect.com/science/article/abs/pii/S87563...
> multiple lines of evidence for material consistent with DNA in dinosaur
After reading a paper I don’t think I’ve ever had a thought like this before: did they run that past a legal team before publication? That sounds like a lawyer wrote it.
The language surprised me too! I realize the researchers wanted to be extra cautious (enough to pass peer-review) and that's the reason I did a literal quote instead of paraphrasing.
The original research [1, section 4] is slightly more cautious (but otherwise agrees):
> It is tempting to suggest that we can now predict the temporal limits of DNA survival, and finally refute the claims of authentic DNA from Cretaceous and Miocene specimens. This is, however, not straightforward. One needs information on the number of template molecules in living tissues, and estimates of post-mortem DNA decay rates for each tissue type. However, the half-life predictions display the extreme improbability that an authentic 174 bp long mtDNA fragment of an 80–85 Myr old bone could have been amplified.
I looked at the paper partly because I was interested in the possibility that some multi-base strands survive, even though such strands would be very short. The "half-life" here was measured by qPCR, where a relatively large amplicon (a fragment being amplicated via PCR) was used. So this study doesn't preclude a possibility of very short (~100 bp) strands surviving, though this would require most enzymes to be much less effective at breaking such strands.
As expected honestly. They found "chemical signals" that indicate DNA in the fossil. Such thing can be anything, from contaminations to errorneous readings. To sequence that supposed "DNA" is a whole other level of technology. In fact, it would be so complex that unless they are hiding alien tech somewhere, I dare say we can't do it at all with our current level of technology.
Researchers explain that the markers cannot be of the microbial origin because they were chosen to only stain DNA in dead cells, and that those markers were highly concentrated at where DNAs would originally have been before the death. So assuming no other obvious mistakes, there may be short (6+ bp) but still readable DNA strands in the fossil.
If there is anything at all... it would pretty much require rewriting the book on DNA preservation, given what we know about this right now I'd say 'impossible' but if there ever is any solid evidence to the contrary I'll be more than happy to admit that I was wrong.
Fossilized means turned to stone. Since DNA is not a crystal, I don't think crystalized DNA is in any way a thing. All the organic stuff, including the DNA, has gone and been replaced with stone in the same shape. But only the same macro shape not the same molecular structures.
> As you'd expect, the embryo was only tiny and measured just 27cm long.
27cm is not exactly what I would call tiny. For comparison, this is what Wikipedia has to say on the topic of ostrich eggs:
> on average they are 15 cm (5.9 in) long, 13 cm (5.1 in) wide, and weigh 1.4 kilograms (3.1 lb)
It's almost twice as long. Talk about megafauna.
Looking for alternative sources, I found this:
> The unhatched dinosaur’s 24-centimetre-long skeleton is curled inside the egg, with its head tucked tightly into its body. The egg is 17 centimetres long and 8 centimetres wide.
Okay, so they were talking about the size of the dinosaur if it stretched out of its curled position inside the egg. The egg meanwhile is a little larger than an ostrich's egg. Still not tiny by any means, but slightly less mindblowing.
Cartilage-only fishes might have been abundant eons ago and they could be as big as a megalodon or even bigger. But because they didn't have teeth, we will never know of them...
A single cell organism somewhere might have hold a miraculous protein or enzyme that test the boundaries of physics or can cure cancer(s). But they are extinct now and we will never know of them.
An ancestor of the octopi might have developed intelligence and tool-making. But since we have no way to find records of their civilization, we will never know of them.
That is why an extinction of a species is so significant. It means they will disappear forever, never to reappear in the exact same form again. We will forever lose them and never know what secret they might have carried in their genome or biology or life.
And yet, there are species going extinct every single day, many of them are due to human...
Probably almost all of it. Taking into account what's left of some of the most durable structures we know about after a few thousand years it stands to reason that most of everything else is gone forever. That's why the older fossil record is so spotty and why almost every find is significant.
Does anyone have a clearer picture of the actual fossil? I don't understand why they chose such a terrible angle for what is the centerpiece of the article.
I know, and we all have seen the movies, but I'd love to see dinosaurs come alive. It should no longer be a new and strange thing in today's world. How bad can it get?
I will start a new Religion and the Dinosaur(s) will be my God(s).
The theory is they needed more oxygen-rich air because the square-cube law means an animal 2X the length, width, height of an elephant has 8X as much mass to deliver oxygen to. The heart can only work so hard, and as far as I know, there has never been a land animal with more than one heart or one set of lungs.
I'm not sure if this theory is still accepted though, as it seems the current consensus is that the air was actually less oxygenated during the dinosaurs' lives.
So we can all agree that the egg definitely came first then? I mean logically that makes sense as this is an egg which contains something other than a chicken...therefore eggs came before chickens. This is a pretty bird-like dinosaur (since dinos ARE birds in a sense) so eventually a dino descendant laid a chicken.
But none of this contain even a miniscule amount of meat or organic material or DNA of a dinosaur. Those already disintegrated aeons ago. DNA half life is around 500 years. After a million years, it would have degraded so bad you literally have nothing left to reconstruct no matter how much sample you discover.
If you start with an entire dinosaur, let say 10 tons, and let be generous and have 1% of that being DNA, you get 1e15 copies of the genome, assuming a 10Gb genome. After 25,000 years, you get less than 1 copy left. Now make it 25 millions years...
I know this "half-life" term is kind of a misnomer since unlike radioisotope where it is unaffected by environmental conditions, DNA "half-life" can be longer depending on things like temperature and pressure. But still, on the scale of millions of years, it becomes exceedingly improbable that we can find even 1 copy of a dinosaur genome left.