Researchers declassify dinosaurs as being the great-great-grandparents of birds

Jul 09, 2014
A skeletal reconstruction of Scansoriopteryx with outlines to indicate the extent of the feathers. Credit: Stephen A. Czerkas

The re-examination of a sparrow-sized fossil from China challenges the commonly held belief that birds evolved from ground-dwelling theropod dinosaurs that gained the ability to fly. The birdlike fossil is actually not a dinosaur, as previously thought, but much rather the remains of a tiny tree-climbing animal that could glide, say American researchers Stephen Czerkas of the Dinosaur Museum in Blanding, Utah, and Alan Feduccia of the University of North Carolina. The study appears in Springer's Journal of Ornithology.

The fossil of the Scansoriopteryx (which means "climbing wing") was found in Inner Mongolia, and is part of an ongoing cooperative study with the Chinese Academy of Geological Sciences. It was previously classified as a coelurosaurian theropod dinosaur, from which many experts believe flying dinosaurs and later birds evolved. The research duo used advanced 3D microscopy, high resolution photography and low angle lighting to reveal structures not clearly visible before. These techniques made it possible to interpret the natural contours of the bones. Many ambiguous aspects of the fossil's pelvis, forelimbs, hind limbs, and tail were confirmed, while it was discovered that it had elongated tendons along its tail vertebrae similar to Velociraptor.

Czerkas and Feduccia say that Scansoriopteryx unequivocally lacks the fundamental structural skeletal features to classify it as a dinosaur. They also believe that dinosaurs are not the primitive ancestors of birds. The Scansoriopteryx should rather be seen as an early bird whose ancestors are to be found among tree-climbing archosaurs that lived in a time well before dinosaurs.

Through their investigations, the researchers found a combination of plesiomorphic or ancestral non-dinosaurian traits along with highly derived features. It has numerous unambiguous birdlike features such as elongated forelimbs, wing and hind limb feathers, wing membranes in front of its elbow, half-moon shaped wrist-like bones, bird-like perching feet, a tail with short anterior vertebrae, and claws that make tree climbing possible. The researchers specifically note the primitive elongated feathers on the forelimbs and hind limbs. This suggests that Scansoriopteryx is a basal or ancestral form of early birds that had mastered the basic aerodynamic maneuvers of parachuting or gliding from trees.

Their findings validate predictions first made in the early 1900's that the ancestors of birds were small, tree-dwelling archosaurs which enhanced their incipient ability to fly with feathers that enabled them to at least glide. This "trees down" view is in contrast with the "ground up" view embraced by many palaeontologists in recent decades that birds derived from terrestrial .

"The identification of Scansoriopteryx as a non-dinosaurian bird enables a reevaluation in the understanding of the relationship between dinosaurs and birds. Scientists finally have the key to unlock the doors that separate dinosaurs from birds," explained Czerkas.

Feduccia added, "Instead of regarding as deriving from , Scansoriopteryx reinstates the validity of regarding them as a separate class uniquely avian and non-dinosaurian."

Explore further: All teeth and claws? New study sheds light on dinosaur claw function

More information: Czerkas, S.A. & Feduccia, A. (2014). Jurassic archosaur is a non-dinosaurian bird, Journal of Ornithology. DOI: 10.1007/s10336-014-1098-9

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MMartyniuk
3.3 / 5 (7) Jul 09, 2014
Why do science news articles always include a quote from a token pseudoscientist when discussing a science paper, but never a quote from an actual scientist when discussing pseudoscience? It doesn't send out any alarm bells that it is always the same group of two or three researchers challenging the consensus? If this kind of blind credulity if reporting were done on a new article from climate deniers it would cause a major scandal.
RobertKarlStonjek
1.4 / 5 (5) Jul 09, 2014
Could birds be the ancestors of dinosaurs?

Sex chromosomes would determine the relationship, but where to find dino DNA?
verkle
1 / 5 (25) Jul 09, 2014
The whole pillars of evolutional theory are teetering. Actually have long ago collapsed. If it were true, there would be billions of fossils whom would provide links between the species we see. But there are basically none. Just individual species. No animal came from another species. There is no science that backs up that idea.
Vietvet
4.8 / 5 (17) Jul 09, 2014
The whole pillars of evolutional theory are teetering. Actually have long ago collapsed. If it were true, there would be billions of fossils whom would provide links between the species we see. But there are basically none. Just individual species. No animal came from another species. There is no science that backs up that idea.

There are a few dumb and ignorant trolls that comment here but your stupidity make them seem brilliant.
InterestedAmateur
4.8 / 5 (17) Jul 09, 2014
@verkle
Your God may need your constant babbling, we don't.
Captain Stumpy
3.6 / 5 (23) Jul 09, 2014
The whole pillars of evolutional theory are teetering
@verkle -aka Alchemist
no... that teetering you are seeing and feeling is the foundation of your religion which has been pulled out from under you by modern science
There is NO room for religion in science, and especially not a religion that tries to change the data to fit the faith (in my day, we called that Lying, or even FRAUD... I guess your religion is more flexible with stuff like that... that would mean that you don't have ten commandments)

JVK
1.1 / 5 (16) Jul 09, 2014
Their theories and classifications keep changing, unlike the biological fact that biodiversity is nutrient-dependent and pheromone-controlled in species from microbes to man.

For information that links biparental feeding to differences in morphological and behavioral phenotypes of white-throated sparrows, see http://www.pnas.o...abstract

Ecological variation is consistently linked via nutrient-dependent amino acid substitutions to ecological adaptations via conserved molecular mechanisms, not by mutation-initiated natural selection.

Stonjek writes: Sex chromosomes would determine the relationship, but where to find dino DNA?

You don't need dino DNA to determine how nutrient-dependent chromosomal rearrangements differentiation cell types, morphology, and behavior. You need to understand conserved molecular mechanisms.
Captain Stumpy
3.6 / 5 (25) Jul 09, 2014
Ecological variation is consistently linked via nutrient-dependent amino acid substitutions to ecological adaptations via conserved molecular mechanisms, not by mutation-initiated natural selection
@jk
so YOUR MODEL has nothing to do with natural selection then?
THANK YOU FOR CLARIFYING THAT, because you've said before that your model causes mutations
remember.. I asked
DOES your model make any changes to the nucleotide sequence of the genome of an organism, virus, or extrachromosomal genetic element?
This is a yes or no answer
THIS is the DEFINITION OF MUTATION- to which you answered
YES!
--Thanks for asking
YOUR WORDS, NOT MINE, mensa boy

You've PROVEN, IN YOUR OWN WORDS, that YOUR MODEL CANNOT BE RESPONSIBLE for natural selection!
zorro6204
4.7 / 5 (12) Jul 09, 2014
Really, this stinks. Presenting this article without noting that one of the researchers cited is a noted gadfly who stands outside accepted science on this point, and the other is a controversial amateur and model maker, is deeply misleading.
TulsaMikel
1.6 / 5 (5) Jul 10, 2014
Evolution at the point of finding links between species is difficult to find. I think it's sufficiently proven but a lot would disagree. I feel species evolution into new species happens at incredibly fast rates due to environmental events that prove to be cataclysmic to a species. The species has to adapt to survive and in doing so simple evolution has it's role but during this cataclysm the population if said species is effected increasing inbreeding thus increasing the chances of beneficial mutations and the change into a more successful species. Finding fossils in these small transition times will be difficult.
antigoracle
1.8 / 5 (5) Jul 10, 2014
So, which came first, the chicken, egg, or the dinosaur?
Francis Bacon
1.5 / 5 (2) Jul 10, 2014
What I find scandalous and stinky are the attitudes being displayed that minority opinions are "pseudoscience" and that opponents of "accepted science" (i.e. the most popular opinion) need to be singled out. Science was designed to make majority opinion worthless, personal backgrounds irrelevant. All that matters in real science is what can actually be demonstrated to be possible, and if possible, can it be demonstrated to actually take place in nature? Even many creationists accept natural selection and evolution of species, but in areas like this, nobody really knows what happened, and from attitudes I've seen displayed elsewhere, there are a lot of people who remind me of little kids in their excitement and desire at the thought of having a dinosaur for Christmas (dinner), etc. A number of the "scientific papers" I've seen have obviously been done by people with an ax to grind and a dream to save, and they are not at all the unbiased, objective reports they should be.
Francis Bacon
4.7 / 5 (3) Jul 10, 2014
verkle, you exaggerate or are ignorant of a number of studies in which the formation of new species has been observed. As to evolution going on without evidence of more than that, keep in mind that modern evolutionary thought began with Darwin's work, in which he admitted that there were major gaps in the evidence for changes beyond what had been observed in breeding and farming domestic crops and animals, and he proposed reasons why such evidences might never be found. He was also wrong about the nature of biological trait inheritance and the major factor in biological change. However, there is no other plausible "scientific" explanation for the existence and diversity of life on Earth than some form of gradual evolution, so there's no reason for the theory to teeter and fall now, after getting along so well without the usual requirements of a scientific theory so far.
JVK
1 / 5 (9) Jul 10, 2014
http://rspb.royal...abstract
"...supports the hypothesis that malaria resistance drove fixation of the Duffy-null allele in mainland sub-Saharan Africa."

Nutrient-dependent amino acid substitutions stabilize the organized genomes of species from microbes to man. Evolutionary theorists seem to have missed out on that fact and also the fact that the physiology of reproduction is controlled by the metabolism of nutrients to species-specific pheromones.

Ignoring those facts causes theorists to assume that mutations and natural selection for malaria resistance enable human biodiversity. Serious scientists know that malaria resistance arises in the context of the nutrient-dependent pheromone-controlled physiology of vitamin-D enhanced genomic stability.

Nutrients and pheromones also drove fixation of alleles associated with 1182 human hemoglobin variants and amino acid substitutions that differentiate all cell types of all individuals.
zorro6204
5 / 5 (5) Jul 10, 2014
" . . . attitudes being displayed that minority opinions are "pseudoscience" . . ."

Not the issue. Opinions outside the mainstream can be expressed. The issue is that the article made it sound like THIS was mainstream science. If they would have printed a comment from a reputable expert in this area, or said something like, these researchers have championed their ideas for years in the face of overwhelming doubts, and hope these new results . . . anything like that, fine. But they didn't, and that was misleading.
Anda
2.7 / 5 (3) Jul 11, 2014
Bullshit study. Period.
Captain Stumpy
2.9 / 5 (15) Jul 11, 2014
So, which came first, the chicken, egg, or the dinosaur?
@aunti-g
the egg
What I find scandalous and stinky are the attitudes being displayed that minority opinions are "pseudoscience" and that opponents of "accepted science" (i.e. the most popular opinion) need to be singled out
@FBacon
Specifically to what are you referring to?

Because someone like JK does not need anyone's sympathy, and he is the worst about having
the unbiased, objective reports they should be
he can't even get the biology/geneticist lexicon down, nor does he comprehend that his own model causes mutations, so his rants against mutation are technically against his own pheromone BS model, which, BTW is PART of evolution (an actual part of how evolution causes biodiversity, but a SMALL part, not THE part, as he claims)

not really clear about where you were going with that... so I will await further clarification.
Francis Bacon
1 / 5 (3) Jul 13, 2014
"...made it sound like THIS was mainstream science. If they would have printed a comment from a reputable expert ..."
More "might makes right" talk. I will grant that for the sake of clear reporting, it should be noted that this is the work of the minority side in a long controversy, but "mainstream science" doesn't mean "the majority opinion" and just because Dr. Feduccia is in the minority doesn't make him any less a "reputable expert" than anyone else, let alone a "pseudoscientist." I see a lot of hate and disrespect going on, but nobody has actually said word one that might count as a scientific criticism.
Quoting the guidelines: Try not to post comments such as... "this is wrong". Be civil... avoiding name calling. Do not make comments that are...obscene, profane...or degrade others. Avoid... religious discussions. Do not engage with trolls...
@Captain Stumpy: No, I was referring to comments regarding the article.
zorro6204
5 / 5 (5) Jul 13, 2014
Yeah but, this isn't just a minority opinion, it's so far out on the bell curve you can't measure it, these guys are basically alone, and they've been alone for years. Anyway, as I said, the point is not whether the article is "right" or "wrong", I'm complaining about the way it was presented, not the content. You don't allow an article on a website like this to present the views of someone who claims he's found howling at the moon cures cancer without explaining that almost all scientists working in the area strongly disagree. Or you shouldn't.
DoieaS
3.9 / 5 (18) Jul 13, 2014
Researchers declassify dinosaurs as being the great-great-grandparents of birds
Isn't it quite evident? How the heavy weight monstrosities like the dinosaurs could serve as an ancestors of lightweight birds? Not to say under the situation, when the first flying birds already existed beside the dinosaurs separately?
What I find scandalous and stinky are the attitudes being displayed that minority opinions are "pseudoscience" and that opponents of "accepted science" (i.e. the most popular opinion) need to be singled out. Science was designed to make majority opinion worthless, personal backgrounds irrelevant.
The answer is easy: the science has evolved into industry designed to drain the money of tax payers as effectively, as it goes..
DoieaS
3.9 / 5 (18) Jul 13, 2014
The whole problem with contemporary paleontology is actually quite simple - the lightweight flying birds with porous skeleton are notoriously known to form the fossils with difficulty. But the contemporary paleontologists believe in evolution, so that when they weren't able to find a reliable fossil of bird ancestor, they simply developed a theory, in which the well known fossils of dinosaurs served as such an ancestor. Such a theory is a product of collective bias, impatience and blind belief in (adaptive power of) evolution.
zorro6204
4.5 / 5 (8) Jul 13, 2014
"How the heavy weight monstrosities like the dinosaurs could serve as an ancestors of lightweight birds?"

Obviously you know little about evolution. Do a little research into what happened after the non-flying dinosaurs were dead. Both the birds and mammals tried to take over those abandoned niches, growing from tiny survivors to monstrous animals, like Elasmotherium a huge type of rhino, or Titanis, a 9 foot tall bird that looks very much like a dinosaur, albeit without the extended tail to balance. Big can get small and vice versa very quickly.
jim_bowers_10
not rated yet Jul 13, 2014
I've been saying that birds evolved from dinosaurs for as long as I can remember. It's rather logical. You have a pre-dinosaur bird like creature that populates an island or isolated continent - then evolves to fill all the ecological niches. Bird begets dinosaur which could easily reevolve back into bird.
strangetruther
1 / 5 (3) Jul 14, 2014
"Francis Bacon" is so right. There are hoards of individuals like MMartyniuk and zorro6204 who aren't qualified research scientists themselves, but who are itching to veto those who are, or any who follow the principles I, or for example "Francis bacon" adhere to.

Few dinobird palaeontologists paid to do the work, have enough of the required skills at the heart of the science to even pretend to do it honestly - which is why we get playground style - and Very pseudoscientific - name-calling. But Feduccia does a far better job than you might expect. Check out http://www.amazon...08AV7HXO , or in the UK http://www.amazon...08AV7HXO , for the full in-depth view from someone who's opened a book or two on scientific principle, and understands the hard science behind it all. Czerkas is far better than most, too.

Martuniuk has no research experience, has done none of the computing you need, & has never designed a scientific experiment of his own. And as for zorro6204?
JVK
1 / 5 (4) Jul 14, 2014
http://www.scienc...abstract

Journal article excerpt: "We take this to mean that the widely assumed role of the distal histidine in compound I formation—acting first as a base catalyst (to deprotonate peroxide) and then as an acid catalyst (to protonate the peroxide oxygen and release water)—needs to be reassessed.'

My comment: When physicists clearly admit to the fact that their assumptions need to be reassessed, it is more difficult for me to understand why evolutionary theorists continue to assume what they were taught to believe about mutation-initiated natural selection is an accurate representation of anything currently known about biophysically-constrained ecological adaptations manifested in biodiversity via conserved molecular mechanisms.
Captain Stumpy
5 / 5 (4) Jul 14, 2014
When physicists clearly admit to the fact that their assumptions need to be reassessed, it is more difficult for me to understand why evolutionary theorists continue to assume what they were taught to believe about mutation-initiated natural selection is an accurate representation of anything currently known
@jk
well, lets see... PHYSICISTS will clearly admit nothing till you can comprehend the lexicon of your own field, which proves that your model creates mutations, per your own words. To which you can ADD the fact that MUTATION initiated natural selection is SUPPORTED by your own model.remember.. I asked
DOES your model make any changes to the nucleotide sequence of the genome of an organism, virus, or extrachromosomal genetic element?
This is a yes or no answer
THIS is the DEFINITION OF MUTATION- to which you answered
YES!--Thanks for asking
YOUR WORDS, NOT MINE
so if you can't ADMIT your own model causes mutations, why should ANYONE else admit anything to you?
Francis Bacon
1 / 5 (2) Jul 14, 2014
@zorro6204: You're still not getting it. Even if there were only 1 person advocating something for a long time despite strenuous opposition from everyone else, that doesn't mean it is bad science. As I said, I'll grant that the title is misleading, making it sound like "scientists" in general are involved rather than a small minority. I'm not sure it's as small as you think, considering there are two or three very influential people on the other side who've had their names on most every significant paper espousing that Birds Are Dinosaurs and I know there are other ornithologists who are not swayed by the paleontologists' arguments and analyses. Certainly far more people want to believe that birds are dinosaurs, but how many have done extensive studies of both birds and dinosaur fossils? At any rate, even if a scientists were opposed by every other scientist in the field, that wouldn't mean his work was comparable to someone claiming "he's found howling at the moon cures cancer."
Francis Bacon
4 / 5 (2) Jul 14, 2014
@DoieaS
You'd best learn more about the facts and the theory before you wade into the discussion. Not all dinosaurs were "heavy weight monstrosities." There were some, such as Compsognathus, which were quite small and light. It also doesn't matter so much if birds lived alongside dinosaurs -- evolution doesn't require one population to go extinct or evolve _en masse_ to evolve a new form.
I believe that science should concern itself with things that can be observed repeatedly by independent, skeptical observers (at least), and if necessary or relevant, clearly demonstrated, or experimentally confirmed under controlled conditions, and these things will also have potential for practical applications. That's how science began, and its that sort of work which has produced all the modern wonders of technology and medicine.
uhoh7
3 / 5 (4) Jul 15, 2014
This article teaches me I cannot trust Phys.org to engage in the slightest vetting of what they put in their headlines. Instead I must personally vet everything if I want to take it all seriously. Time to find another science news site which avoids complete drivel like this article.
DoieaS
1 / 5 (1) Jul 15, 2014
The furcula, or wishbone is a forked bone present in most modern birds and not seen in any other extant animal group. That they've been found in several theropod dinosaur groups is one of the key pieces of evidence that birds are directly descended from theropod dinosaurs
Dr_toad
not rated yet Jul 15, 2014
Zeph, here you're right, but I downvote you everywhere and anywhere I find your miserable scat.