In 2005 the unexpected occurred; researchers reported what appeared to be preserved soft tissues inside the femur of a Tyrannosaurus rex excavated from the Hell Creek Formation. Structures that looked like blood vessels and blood cells were seen under the microscope, and although it is still unknown whether this is original organic material or material that has somehow been preserved the structures provided some tantalizing clues. What the researchers have been more confident about, however, is that they were able to detect the presence of preserved collagen proteins in the material. (Indeed, research carried out in 1999 on the remnants of feathers of Shuvuuvia illustrated that proteins have the potential to survive over tens of millions of years.)
In a Science paper published last year it was announced that the proteins most closely matched those from chickens supporting the notion that ancient proteins can be preserved in the fossil record. A short communication published just this past spring again confirmed the 2007 protein test results (although the phylogenetic tree that was produced lacked resolution), and a 2007 report published in the Proceedings of the Royal Society B suggested that such preservation of soft tissues might exist even from Triassic bones. There may be plenty of previously unseen treasures in bones stored in museums.
Now along comes a new PLoS paper that brings all these announcements about Tyrannosaurus soft tissue into question. Sampling a variety of genera from Hell Creek and elsewhere, researchers hypothesize that the structures that look like blood vessels and cells from the famous Tyrannosaurus femur are really just biofilm, slimy accumulations of bacteria that oozed into the bone and took the shape of the structures. What's more, the published data from the Tyrannosaurus protein studies showed the presence of at least some bacterial contamination, and the authors of the PLoS paper suggest that the bacteria might have contained collagen-like proteins and therefore made the findings of the earlier studies ambiguous. The question is whether this new paper is going to stand up to scrutiny.
Does this new paper sound the death knell for ancient dinosaur proteins? Certainly not. It is a new alternative explanation that offers up a hypothesis and should be treated with scrutiny (just as any other paper). The analysis of the proteins said to have been taken from the Tyrannosaurus material published last year have been criticized, as well, so there's definitely still room for debate here.
As Jerry Harris aptly noted in a comment on this subject over at Aetiology the new PLoS paper primarily looks at morphology of the bacteria rather than the biochemistry of it, thus putting it more at odds with the 2007 survey of potential preserved soft tissues than the analysis of the proteins. It's like judging how good a wine is by beer criteria; one doesn't necessarily contradict the other. I'm sure more papers will be published about the potential Tyrannosaurus proteins but until then it would be foolish to say that the preserved structures are "just biofilm" or to unquestionably accept that the material really is preserved Tyrannosaurus goo. More work needs to be done, and I certainly look forward to seeing how molecular biology and paleontology come together over the coming years.
- Log in to post comments
Brian,
Just FYI, Tom Kaye is answering questions over at Panda's Thumb.
Yeah, it's a good debate and I'm actually glad that the T. rex protein data is getting so much scrutiny, as I think it falls into the "extraordinary claim" category at this point. I was always puzzled by a remark by Asara and Schweitzer in their reply to the technical comment you linked to above:
"...and amphibians are neither native to nor present at Hell Creek, nor have they ever been present in either of the labs where analysis was performed."
I suppose we have to take their word that the labs have never been exposed to possible amphibian contamination (although it seems strange that no amphibian, living or dead has ever wound up in a lab at some point). But, no amphibians at Hell Creek???
Well, Montana Fish and Wildlife lists three native species of amphibian at Hell Creek State Park. Presuming that Asara and Schweitzer mean the MOR 1125 locality and not the Creek itself, it's still difficult to imagine any setting in the lower 48 that doesn't have some species of resident or transient amphibian, except perhaps at very high altitudes.
A trivial point perhaps, but if such a seemingly unusual claim can be made with such blatant certainty and without any source to back it up, this tends to amplify my skepticism about the other claims being made (fairly or unfairly).
I worry that many paleophiles will fall into Mulder syndrome: wanting to believe in preserved T. rex soft tissue so much that they are less critical of the data than they should be....
Mulder syndrome...I'll have to remember that one!
You beat me to it, Brian. I'll probably blog on this later today or tomorrow. I'm not really sold on the idea that it's bacterial slime, but I have to read the paper a little "closer" before I make my final judgement.
At least some people will quit saying that "T.rex is just an overgrown chicken" and stupid stuff like that!
And to the ones who misunderstood the bacteria for genuine proteins when they analyzed the bone...a big,Nelson-esque "A-AH!"
Based on the summaries I'm seeing (I'm not technical enough to tackle the full paper, alas), it sounds like, even if the biofilm hypothesis ultimately proves correct, the biofilm itself seems to have copied the structure of the T. rex soft tissue. Is that right? Sounds like that would still be a momentous discovery, if not quite as awesome as having actual preserved T. rex soft tissue.
thanks.
This is a good example of why it's important to be cautious in science, and to realize evidence can have more than one explanation. The protein advocates could well be right, so I'll wait and see how the debate plays out, and what new discoveries are made. The worst part of this controversy is the claim (outrageous, if unsurprising) by creationists that if proteins did survive, it means the fossils of the T-rex were only thousands, not tens of millions of years old! Oh well, they're nothing if not consistent. I'll be eagerly awaiting more research on this matter.
it means the fossils of the T-rex were only thousands, not tens of millions of years old! Oh well, they're nothing if not consistent. I'll be eagerly awaiting more research on this matter.
thousands, not tens of millions of years old! Oh well, they're nothing if thousands, not tens of millions of years old! Oh well, they're nothing if not consistent. I'll be eagerly awaiting more research on this matter.
Büyükçekmece Belediye BaÅkanı Hasan Akgün, "Mesut'u 5 yıl önce Türkiye'ye getirdim ama Galatasaray, "Bu çocuk çok cılız. Solucan gibi" deyip beÄenmedi. BeÅiktaÅ da yüzüne
housands, not tens of millions of years old! Oh well, they're nothing if thousands, not tens of millions of years old! Oh
rchers hypothesize that the structures that look like blood vessels and cells from the famous Tyrannosaurus femur are really just biofilm, slimy accumulations of bacteria that oozed into the bone and took the shape of the structures. What's more, the published data from the Tyrannosaurus protein studies showed the presence of at least some bacterial contamination, and the authors of the PLoS paper suggest that the bacteria might have contained colla
03 in the UK, Sweden, Austria, Italy, Hong Kong and Australia. Using the company called Three which has been like one of the first 3G and HSDPA operators in Europe, Australia and Hong Kong.
Compared to that, the iPhone doesn't really bring anything new, other then crappy iTunes lock-in (that you have to forever in the future buy your music and videos from Steve
YÃK BaÅkanı Prof. Dr. Yusuf Ziya Ãzcanâın yazısı üniversite koridorlarında da öÄrencilerin gündemine geldi. Ä°stanbul Ãniversitesi Tıp Fakültesiânde yetkililer âaçıklamaâ yapmazken, bahçede oturan öÄrencilere âYÃKâün uyarıâ yazısını sorduk.
urther, embracing a big-tent approach will not prevent scientific or even atheistic values from taking over. While the majority of the American public is religious, the number of atheists is growing. New atheists will be created in the same way that new atheists have always been created
http://www.karmod.eu
At least some people will quit saying that "T.rex is just an overgrown chicken" and stupid stuff like that!..Very Very ve Very good...
housands, not tens of millions of years old! Oh well, they're nothing if thousands, not tens of millions of years old! Oh
60 ülkede Karmod Karmod kalitesiyle bugüne gelindiginde 58 ülkede ürünü bulunan bir marka konumundadir. iklim kosulu olursa olsun farketmez. http://www.kartalprefabrik.com
than the temporary direct traffic from the links. But since I kept the proper keyword in the title, people who linked to the post used the title as anchor text, and the post got more
http://www.bighaber.com
no problem, but you needed to know the internal working of the system well, now there is more abstraction to the configuration.
http://www.traverten.net
en iyi iddaa sitesi ve justin tv izleme sitesi kesinlikle iddaalive..daha ne olsun sitede maç izle justin tv izle iddaa tahminleri yorumları maç özetleri canlı tv canlı radyo ne arasan var
500 hours, let alone 5,000 hours, get pretty tough to estimate accurately without spending a lot of time on the estimate
If you highlight a tweet from one of the people youâre following, the same thing would happen in your second timeline.
Tyrannosaurus protein studies showed the presence of at least some bacterial contamination, and the authors of the PLoS paper suggest that the bacteria might have contained colla
eah, it's a good debate and I'm actually glad that the T. rex protein data is getting so much scrutiny, as I think it falls into the "extraordinary claim" category at this point. I was always puzzled by a remark by Asara and Schweitzer in their reply to the technical comment you linked to above:
"...and amphibians are neither native to nor present at Hell Creek, nor have they ever been present in either of the labs where analysis was performed."
I suppose we have to take their word that the labs have never been exposed to possible amphibian contamination (although it seems strange that no amphibian, living or dead has ever wound up in a lab at some point). But, no amphibians at Hell Creek???
Well, Montana Fish and Wildlife lists three native species of amphibian at Hell Creek State Park. Presuming that Asara and Schweitzer mean the MOR 1125 locality and not the Creek itself, it's still difficult to imagine any setting in the lower 48 that doesn't have some species of resident or transient amphibian, except perhaps at very high thankss
eah, it's a good debate and I'm actually glad that the T. rex protein data is getting so much scrutiny, as I think it falls into the "extraordinary claim" category at this point. I was always puzzled by a remark by Asara and Schweitzer in their reply to the technical comment you linked to above:
"...and amphibians are neither native to nor present at Hell Creek, nor have they ever been present in either of the labs where analysis was performed."
I suppose we have to take their word that the labs have never been exposed to possible amphibian contamination (although it seems strange that no amphibian, living or dead has ever wound up in a lab at some point). But, no amphibians at Hell ,
eah, it's a good debate and I'm actually glad that the T. rex protein data is getting so much scrutiny, as I think it falls into the "extraordinary claim" category at this point. I was always puzzled by a remark by Asara and Schweitzer in their reply to the technical comment you linked to above:
"...and amphibians are neither native to nor present at Hell Creek, nor have they ever been present in either of the labs where analysis was performed."
I suppose we have to take their word that the labs have never been exposed to possible amphibian contamination (although it seems strange that no amphibian, living or dead has ever wound up in a lab at some point). But, no amphibians at Hell articles
Tyrannosaurus protein studies showed the presence of at least some bacterial contamination, and the authors of the PLoS paper suggest that the bacteria might have contained colla
Tyrannosaurus protein studies showed the presence of at least some bacterial contamination, and the authors of the PLoS paper suggest that the bacteria might have contained colla
eah, it's a good debate and I'm actually glad that the T. rex protein data is getting so much scrutiny, as I think it falls into the "extraordinary claim" category at this point. I was always puzzled by a remark by Asara and Schweitzer in their reply to the technical comment you linked to above:
"...and amphibians are neither native to nor present at Hell Creek, nor have they ever been present in either of the labs where analysis was performed."
I suppose we have to take their word that the labs have never been exposed to possible amphibian contamination (although it seems strange that no amphibian, living or dead has ever wound up in a lab at some point). But, no amphibians at Hell Creek???
Well, Montana Fish and Wildlife lists three native species of amphibian at Hell Creek State Park. Presuming that Asara and Schweitzer mean the MOR 1125 locality and not the Creek itself, it's still difficult to imagine any setting in the lower 48 that doesn't have some species of resident or transient amphibian, except perhaps at very high thankss
eah, it's a good debate and I'm actually glad that the T. rex protein data is getting so much scrutiny, as I think it falls into the "extraordinary claim" category at this point. I was always puzzled by a remark by Asara and Schweitzer in their reply to the technical comment you linked to above:
I was always puzzled by a remark by Asara and Schweitzer in their reply to the technical comment you linked to above
feature articles at the intersection of science and culture. The response I got was almost uniformly the same. Not only were the magazines not interested in dinosaurs, but illustrations of dinosaurs were not art. As M.J.T. Mitchell explained in his
Tyrannosaurus femur are really just biofilm, slimy accumulations of bacteria that oozed into the bone and took the shape of the structures. What's more, the published data from the Tyrannosaurus protein studies showed the presence of at least some bacterial contamination, and the authors of the PLoS paper suggest that the bacteria might have contained collagen-like proteins and therefore made the findings of the earlier studies ambiguous. The question is whether this new paper is going to stand up to scrutiny.
sections there is sometimes the tendency to jump around, and as a whole the book lacks a strong narrative voice.
Turkey can always be dismissed as an outlier, but, just the same, it can serve as a model for what we might expect from other
urkish PM Recep Tayyip Erdogan has offered to mediate between the U.S. and Turkey.
Turkey can always be dismissed as an outlier, but, just the same, it can serve as a model for what we might expect from other
Good for you and hope for the rest of us!
I suppose we have to take their word that the labs have never been exposed to possible amphibian contamination (although it seems strange that no amphibian, living or dead has ever wound up in a lab at some point). But, no amphibians at Hell ,
eah, it's a good debate and I'm actually glad that the T. rex protein data is getting so much scrutiny, as I think it falls into the "extraordinary claim" category at this point. I was always puzzled by a remark by Asara and Schweitzer in their reply to the technical comment you linked to above..
Well, Montana Fish and Wildlife lists three native species of amphibian at Hell Creek State Park. Presuming that Asara and Schweitzer mean the MOR 1125 locality and not the Creek itself, it's still difficult to imagine any setting in the lower 48 that doesn't have some species of resident or transient amphibian, except perhaps at very high altitudes.
A trivial point perhaps, but if such a seemingly unusual claim can be made with such blatant certainty and without any source to back it up, this tends
Branda
brandacı
branda kumaÅ
branda çeÅitleri
branda tente
focused article on the topic and sent it out to magazines purported to feature articles at the intersection of science and culture.
focused article on the topic and sent it out to magazines purported to feature articles at the intersection of science and culture.
urther, embracing a big-tent approach will not prevent scientific or even atheistic values from taking over. While the majority of the American public is religious, the number of atheists is growing. New atheists will be created in the same way that new atheists have always been created
focused article on the topic and sent it out to magazines purported to feature articles at the intersection of science and culture.
very good.
eature articles at the intersection of science and culture. The response I got was almost uniformly the same. Not only were the magazines not interested in dinosaurs, but illustrations of dinosaurs were not art. As M.J.T. Mitchell explained in his
Based on the summaries I'm seeing (I'm not technical enough to tackle the full paper, alas), it sounds like, even if the biofilm hypothesis ultimately proves correct, the biofilm itself seems to have copied the structure of the T. rex soft tissue. Is that right? Sounds like that would still be a momentous discovery, if not quite as awesome as having actual preserved T.
Based on the summaries I'm seeing (I'm not technical enough to tackle the full paper, alas), it sounds like, even if the biofilm hypothesis ultimately proves correct, the biofilm itself seems to have copied the structure of the T. rex soft tissue. Is that right? Sounds like that would still be a momentous discovery, if not quite as awesome as having actual preserved T.
take their word that the labs have never been exposed to possible amphibian contamination (although it seems strange that no amphibian, living or dead has ever wound up in a lab at some point). But, no amphibians at Hell ,
eah, it's a good debate and I'm actually glad that the T. rex protein data is getting so much scrutiny, as I think it falls into the "extraordinary claim" category at this point. I was always puzzled by a remark by Asara and Schweitzer
She is one of my public schooled kiddos who is getting really involved with helping out at school
nofollow olmasına raÄmen neden yapıyoruz halen anlamıŠdeÄilim.