Dinosaurs may have been warm-blooded: study

Jun 27, 2012
A baby Tyrannosaurus Rex shows its teeth as it promotes a theatrical show in New York in 2010. Dinosaurs may have been warm-blooded, scientists said Wednesday, in a finding that could debunk one of the most commonly-held images of the extinct giants.

Dinosaurs may have been warm-blooded, scientists said Wednesday, in a finding that could debunk one of the most commonly-held images of the extinct giants.

Researchers in Spain and Norway reported in the journal Nature they had found tree-like on the bones of mammals, a feature that until now was thought to be limited to cold-blooded creatures ... and dinosaurs.

They also found evidence that dinosaurs probably had a high metabolic rate to allow fast growth -- another indicator of warm-bloodedness.

"Our results strongly suggest that dinosaurs were warm-blooded," lead author Meike Koehler of Spain's Institut Catala de Paleontologia told AFP.

If so, the findings should prompt a rethink about reptiles, she said.

Modern-day reptiles are cold-blooded, meaning they cannot control their through their own -- relying instead on external means such as basking in the sun.

While the dinosaurs may have been warm-blooded, their other characteristics kept them squarely in the reptile camp, said Koehler.

Palaeontologists have long noted the ring-like markings on the bones of cold-blooded creatures and dinosaurs, and taken them to indicate pauses in growth, perhaps due to cold periods or lack of food.

The bones of warm-blooded animals such as birds and mammals had never been properly assessed to see if they, too, exhibit the lines.

Koehler and her team found the rings in all 41 warm-blooded they studied, including antelopes, deer and giraffes.

The finding "eliminates the strongest argument that does exist for cold-bloodedness" in dinosaurs, she said.

The team's analysis of also showed that the fast growth rate of mammals is related to a , which in turn is typical of warm-bloodedness.

"If you compare this tissue with dinosaur tissue you will see that they are indistinguishable," said Koehler.

"So this means that dinosaurs not only grew very fast but this growth was sustained by a very high metabolic rate, indicating warm-bloodedness."

A comment by University of California palaeontologist Kevin Padian that was published with the paper said the study was the latest to chip away at the long-held theory that were cold-blooded.

"It seems that these were anything but typical reptiles, and Koehler and colleagues' findings remove another false correlation from this picture."

Explore further: New evidence of ancient rock art across Southeast Asia

More information: DOI: 10.1038/nature11260

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chasehusky
3.2 / 5 (9) Jun 27, 2012
It's frustrating that writers commenting on research articles seem to have an aversion to actually linking to the article, let alone just providing a base citation.

M. Köhler, N. Marín-Moratalla, X Jordana, and R. Aanes, "Seasonal bone growth and physiology in endotherms shed light on dinosaur physiology", Nature, 2012. [doi:10.1038/nature11264]

http://www.nature...264.html
Phrog
3.2 / 5 (6) Jun 27, 2012
What i get from this story is that dinosaurs had a high enough temperature to have a high metabolic rate. No evidence presented of regulatory control system. Environmental temps at time of T Rex were warmer so behavior could regulate temp at higher value. I would like to see more evidence.
lonewolfmtnz
2 / 5 (8) Jun 27, 2012
Since when has rampant unsubstantiated speculation been consider as "science". Is it me, or has the quality of (alleged) 'reporting' on this site exponentially deteriorated?
Vendicar_Decarian
3.8 / 5 (10) Jun 27, 2012
The link is right there at the end of the article. After "more information: "

"Since when has rampant unsubstantiated speculation" - LoneTard

Growth rings found (non-speculation)

"Koehler and her team found the rings in all 41 warm-blooded animal species they studied, including antelopes, deer and giraffes.

The finding "eliminates the strongest argument that does exist for cold-bloodedness" in dinosaurs, she said."

No Comprehedie muchlie LoneTard?
Shakescene21
5 / 5 (4) Jun 27, 2012
Once it was recognized that birds are descended from dinosaurs, the dinosaurs-are-cold-blooded theory was headed toward extinction.
julianpenrod
1.2 / 5 (11) Jun 28, 2012
A good example of the state of the "science" so many praise for its reliability. The structure of cells and blood vessels, the presence of offensive trappings such as Deinonychus' claws, which would be most useful in rapid attacks, were supposed to already point to warm bloodedness. Indeed, it was taken as all but proved decades ago and "scientists" inserted the idea into their interpretation of new findings. Now, it's admitted that it's still far from proved!
More than that, note the reference to the bones of known endotherms never having been "properly assessed to see if they, too", exhibit growth rings. In other words. the "conclusion" that dinosaurs were clood blooded like reptiles was based on their having rings that no "scientist" knew for sure mammals and birds didn't also have!
How many times does it have to keep repeating before more realize "scientists" don't know what they're saying, their "proof" is only doggerel, and they can't be trusted in anything?
Vendicar_Decarian
4.2 / 5 (10) Jun 28, 2012
Poor Julian. It concludes that paleontologists are deciding if dinosaurs were warm or cold blooded based on a single line of evidence.

That presumption is entirely false.

"How many times does it have to keep repeating before more realize "scientists" don't know what they're saying, their "proof" is only doggerel, and they can't be trusted in anything?" - JulianTard

What this article is telling you, and what you are not intellectually equipped to absorb, is that there are many lines of evidence pointing to different conclusions, and that one line of evidence - a lack of growth rings in cold blooded animals compared to warm blooded animals, has been shown to be false, and hence can not be applied to the problem as it has been.

chasehusky
5 / 5 (2) Jun 28, 2012
The link is right there at the end of the article.


The link/DOI information wasn't included at the end of the physorg article when I originally posted my comment.
julianpenrod
1.8 / 5 (5) Jun 28, 2012
Again, a technique of New World Order non argument. Vendicar Decarian quotes my objection as that "paleontologists" "conluded" that dinosaurs are warm or cold blooded "based on a single line of evidence".
In fact, I pointed out two lines of evidence said to prove dinsoaurs were warm blooded! What I was pointing out was the artticle's own admission that endotherms "were never propely assessed" to see if they also have bone growth rings! And, yet, on the basis of, as the article admits, not knowing if endotherms had groewth rings, they insisted dinosaurs had a reptilian trait and so probably were ectotherms! They were making a judgment based on information the article admits they didn't have!
And note how many readily give Vendicar Decarian five stars for a patent act of character assassination, yet never gave me the same for pointing out that "scientists" were coming to "conclusions" based on information they didn't have.
Shamuss
3 / 5 (4) Jun 28, 2012
ofcourse they were warm-blooded, the earth is only 5000 years old and jesus and his followers would have found cold-blooded dinosaur-horses too slow to ride in the winter time..
Vendicar_Decarian
3.4 / 5 (5) Jun 28, 2012
Louisiana Private Schools Teach Loch Ness Monster Is Real In Effort To Disprove Evolution Theory

This is what free Market education produces.

From the Text being used:

"Are dinosaurs alive today? Scientists are becoming more convinced of their existence. Have you heard of the `Loch Ness Monster' in Scotland? `Nessie,' for short has been recorded on sonar from a small submarine, described by eyewitnesses, and photographed by others. Nessie appears to be a plesiosaur."

TheGhostofOtto1923
4.2 / 5 (15) Jun 28, 2012
In other words. the "conclusion" that dinosaurs were clood blooded like reptiles was based on their having rings that no "scientist" knew for sure mammals and birds didn't also have!
How many times does it have to keep repeating before more realize "scientists" don't know what they're saying, their "proof" is only doggerel, and they can't be trusted in anything?
This is called progress. As VD instantiates with the above excerpt, religionists are not making progress. At all.

Every new thing that scientists learn is one less thing that religionists can claim they know. Generally speaking. You guys lose ground every day whether you are willing to admit it or not.

Refusal to admit it is a hallmark of faith.
TheGhostofOtto1923
4.2 / 5 (15) Jun 28, 2012
It could be that warm blood/cold blood is just a recurring option for many species like fur or hibernation or saber tooth, employed to suit conditions and enhance survival. Like this goat:
http://phys.org/n...tml#nRlv
julianpenrod
1 / 5 (4) Jun 28, 2012
A New World Order non argument technique by TheGhostofOtto1923, the lie. The article itself states that "scientists" claimed growth rings were characteristic only of ectotherms without checking endotherms to verify that. That is a blatant violation of the rules of "science", to make a statement without proof. Yet TheGhostofOtto1923 declares that that is "progress", not knowing about growth rings in endotherms then learning about it. New World Order quislings have no sincerity, no honor. They have no problem whitewashing when "scientists" violate the rules of "science" for their own purposes.
davhaywood
5 / 5 (3) Jul 01, 2012
Has anybody caught the beautiful irony in Julian's incredulity toward science and scientific progress while sending us messages on his PC? Julian, I suggest you renounce any and all scientifically-derived commodities you enjoy, then you may credibly argue with us. I assume you'll be delivering your replies to us in person, on foot. That is, if you can survive the journey. Here is a nice training program: http://www.oregon...ontrail/

Julian prides himself on his logic and knowledge, while he is clearly a dualist, which has long been discredited in the philosophy of mind. Who has their head in the sand, now, Julian?
davhaywood
4.5 / 5 (2) Jul 01, 2012
To sum up, do scientists make mistakes? Of course. Do they have a monopoly on knowledge, of course not. This is why science has a self-correcting mechanism built into its structure. Though, I will say science has been the most productive source of knowledge yet. The only institutions and people who have the hubris to believe they hold the definitive truth are individuals like yourself, Julian, who believe that what exists in their head or in an ancient book are the fountainhead of knowledge.

You seem like an intelligent person, Julian. Likely more intelligent than many of the people who you argue with. You are familiar with logic and physics it seems, and you are quite literate and erudite. It truly is a shame you've let that be wasted on self-aggrandizement and delusion.

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