from the I-don't-remember-this-in-the-film dept.
Abstract: http://link.springer.com/article/10.1007%2Fs10336-014-1098-9
By re-examining a fossil of Scansoriopteryx (which means "climbing wing"), a sparrow-size creature from the Jurassic era, researchers believe that the commonly held belief that birds evolved from ground-dwelling theropod dinosaurs that gained the ability to fly is false. 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.
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 manoeuvres 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 theropod dinosaurs.
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The first ever example of a plant-eating dinosaur with feathers and scales has been discovered in Russia. Previously only flesh-eating dinosaurs were known to have had feathers so this new find indicates that all dinosaurs could have been feathered.
(Score: 3, Insightful) by Darth Turbogeek on Friday July 11 2014, @12:12AM
One fossil remains of the sole existing found example, in a science where guesswork is ofen used as real evidence is missing.
http://en.wikipedia.org/wiki/Scansoriopteryx [wikipedia.org]
So there is also doubt about it's age and location of find too. Yeeeeaaaaah sorry, but this is an interesting theory only and doesnt cast much doubt on anything. You really cant make any kind of statement of authority on this at all.
(Score: 2) by frojack on Friday July 11 2014, @12:41AM
Even one fossil is evidence. But I believe there are two: IVPP V12653 and CAGS02-IG-gausa-1/DM 607.
For instance, the images in the links, yours and the TFS, are remarkably different than something like a rat [biologycorner.com] or a squirrel [wordpress.com] skeleton. Yet they are significantly different to some of the bigger things we associate with early birds [fossilmuseum.net].
Like so much in nature, I wouldn't be surprised to find flight evolving in more than one place at slightly different times.
No, you are mistaken. I've always had this sig.
(Score: 1) by subs on Friday July 11 2014, @08:12AM
> Yet they are significantly different to some of the bigger things we associate with early birds.
Which is not really surprising considering pterosaurs aren't dinosaurs.
(Score: 2) by evilviper on Friday July 11 2014, @08:13AM
It's all intellectual masturbation until we have something more than a few random fossils to work from. Guessing what animal evolved from which other, based on visual clues, has proven quite inaccurate, time and time again, with completely unrelated animals developing nearly identical physical traits. It's only the advent of DNA sequencing that has injected some real, scientific rigour into the process, replacing the bald-ass guesswork.
DNA sequencing has been pushing further and further into the past. Getting close to 1million years now, and still going. One frozen chunk of dinosaur is all we need to settle the argument.
http://www.theguardian.com/science/2013/jul/07/prehistoric-horse-dna-genome-sequence [theguardian.com]
Until we've got some dino DNA, both sides are full of crap, and making claims with no decent evidence. In other words, both sides may be right, or (more likely) both sides may be completely wrong. For all anyone knows, birds could have evolved from some other species, that has completely eluded our observations of the (very sparse) fossil record thus far.
Hydrogen cyanide is a delicious and necessary part of the human diet.
(Score: 2) by GreatAuntAnesthesia on Friday July 11 2014, @11:32AM
> One frozen chunk of dinosaur is all we need
Good luck with that.
(Score: 2) by evilviper on Friday July 11 2014, @02:18PM
There were dinosaurs in Antarctica.
http://news.nationalgeographic.com/news/2004/03/0309_040309_polardinos.html [nationalgeographic.com]
Much of the continent has been frozen for tens of millions of years.
There hasn't been much effort to look for dinosaurs in the deep freeze. It's likely there are there, to be found. But no rush... DNA science needs quite a few more years.
Hydrogen cyanide is a delicious and necessary part of the human diet.
(Score: 3, Informative) by Immerman on Friday July 11 2014, @03:51PM
The question is if there were any dinosaur remains left by the time the deep-freeze set in. Remember that the dinosaurs pretty much died out 64 million years ago, long before Antarctica migrated to the south pole. Meaning that any remains would have to have survived with intact DNA for tens of millions of years before being frozen. Even if you somehow got a fresh whole dinosaur frozen in the ice it's still a dicey proposition - after all freezing mostly stops rot and other biological degradation, but only slows chemical degradation a little.
(Score: 2, Interesting) by ld a, b on Friday July 11 2014, @02:09PM
No guesswork needed. I still haven't read the article, but this fossil is either fake or misidentified.
There is no such thing as a non-dinosaurian archosaur that is the ancestor of birds because birds are used for the current definition of dinosauria. So any weird archosaur in between is by definition a dinosaur.
Leaving classification aside, dinosaurs including birds form a clear-cut group. The egg comes first. Pterosaurs are the closest archosaur group and they had reptile-like leathery eggs. All dinosaurs including birds have hard-shelled eggs sharing the exact same structure. The sex of a female T. Rex was identified because it shared the same bone structure modern female birds use to calcify eggs. Air sacs have been identified as basal saurischian traits as well. Then there are all the classical bone features which group them all up to the saurischia-ornithischia divide.
Birds had to branch off pretty early because they were a around from very early on. They can't be derived from the dinosaurs most people are familiar with. That much is true. The branch can be very early but it must include all of coleurosauria as they have been shown to have feathers while ornithischia were covered by scutes. You need to explain why a T. rex evolved from this birdo-saur monkey to end up looking mostly like a derived theropod.
If it looks like a dinosaur, walks like a dinosaur, breeds like a dinosaur, breathes like a dinosaur and quacks like a dinosaur...
10 little-endian boys went out to dine, a big-endian carp ate one, and then there were -246.