Another Oldest Bird

[ZoPteryx]

Meet Aurornis xui, a bird older than Archaeopteryx, according to some anyway.

http://news.yahoo.com/blogs/sideshow/fossil-remains-may-contain-world-first-bird-specimen-204043494.html

http://en.wikipedia.org/wiki/Aurornis





And just for fun, there's also a new basal therizinosaur on the block:
http://en.wikipedia.org/wiki/Jianchangosaurus

[Splonkadumpocus]

The phylogenetic analysis for Aurornis also found Anchiornis, Balaur, Rahonavis, and Xiaotingia to be birds.

[tyrantqueen]

That's a very ugly piece of artwork...

[Patrx]

That's a very ugly piece of artwork...

Quite so, and from such a lovely fossil, no less. Poor thing looks like it's been given eyebrows.

[Pachyrhinosaurus]

The phylogenetic analysis for Aurornis also found Anchiornis, Balaur, Rahonavis, and Xiaotingia to be birds.

If balaur is now a bird, then does that mean that the other dromaeosaurs were birds as well?

[Hermes888]

I thought Archeopteryx was no longer considered the first bird? The line distinguishing what makes a dinosaur considered a bird or not is blurring so much nowadays, and I love it!

[Splonkadumpocus]

The phylogenetic analysis for Aurornis also found Anchiornis, Balaur, Rahonavis, and Xiaotingia to be birds.

If balaur is now a bird, then does that mean that the other dromaeosaurs were birds as well?

Dromaeosauridae is still together, basal to a Troodontidae+Avialae clade. Balaur wound up outside Dromaeosauridae as an avialan.

[Dinoguy2]

I thought Archeopteryx was no longer considered the first bird? The line distinguishing what makes a dinosaur considered a bird or not is blurring so much nowadays, and I love it!

One big issue is figuring out just what "bird" even means. Traditionally the clade Archaeopteryx + modern birds was referred to as "birds", but now the consensus seems to be that Avialae (everything closer to modern birds than to troodontids and dromaeosaurids) are "birds".

So just a few years ago, when Epidexipteryx was considered an avialan, it was not considered the oldest "bird" because it was still more primitive than Archaeopteryx. Nowadays Epidexipteryx is thought to be a primitive maniraptoran so it's still not a bird, but things like Anchiornis and Aurornis are now considered birds despite being more primitive than Archaeopteryx.  I personally like the new definition of bird better than the old one, since it made Archie the oldest bird by default forever, which seems like rigging the game to me. At least now we have the possibility/excitement of making discoveries of older "birds" other than Archie.

It didn't help that the media picked up on the whole "Archaeopteryx is not a bird" thing. That was based on one really kinda poorly done study that found Archie closer to dromaeosaurs than to modern birds, making it not a "bird" under the new definition of bird (it would still have been a bird under the old definition, along with dromaeosaurs). A new study very quickly showed why that study was wrong, and most studies since then have continued to show it was wrong, but the media didn't pick up on the correction until now.

That's why there are now so many headlines like "Archaeopteryx restored to its position as a bird" despite the fact that that happened years ago, and it's status as non-bird lasted only a few months as far as science is concerned.

[Dinoguy2]

(sorry, double-post)

[ZoPteryx]

That's a very ugly piece of artwork...

Quite so, and from such a lovely fossil, no less. Poor thing looks like it's been given eyebrows.

I agree, here's something it bit more soothing.

The phylogenetic analysis for Aurornis also found Anchiornis, Balaur, Rahonavis, and Xiaotingia to be birds.

Well, three of those have always been a little controversial, but Balaur surprises me.  What sort of bird would it be anyway, a gigantic flightless enantiornith?!  Still, their analysis apparently had something like over 700 characters, pretty compelling, even if Balaur isn't known from material as complete as the others.

[Hermes888]

Thanks Dinoguy2. Is there a good place to get up-to-date and reliable information in paleontology news?

[Dinoguy2]

That's a very ugly piece of artwork...

Quite so, and from such a lovely fossil, no less. Poor thing looks like it's been given eyebrows.

I agree, here's something it bit more soothing.

The phylogenetic analysis for Aurornis also found Anchiornis, Balaur, Rahonavis, and Xiaotingia to be birds.

Well, three of those have always been a little controversial, but Balaur surprises me.  What sort of bird would it be anyway, a gigantic flightless enantiornith?!  Still, their analysis apparently had something like over 700 characters, pretty compelling, even if Balaur isn't known from material as complete as the others.

According to the analysis, it's the sister group to avebrevicaudans. But given that the tail and skull isn't known, it could be a big short-tailed flightless bird (like Patagopteryx), a big long-tailed flightless herbivorous bird similar to Jeholornis with a longer tail, or a big carnivorous flightless winged animal like dromaeosaurs and troodonts, only slightly more advanced. Given the claws, I'd guess the latter. The "dromaeosaur" body plan seems common for basal flightless birds due to convergence from the same basic ancestors, similar to the way modern flightless birds tend to end up looking the same despite descending from multiple different flying ancestors.

[Splonkadumpocus]

With regards to Balaur, large flightless birds do tend to evolve on islands. Note especially the dodo, elephant bird, kiwi, and moa.

[Dinoguy2]

With regards to Balaur, large flightless birds do tend to evolve on islands. Note especially the dodo, elephant bird, kiwi, and moa.

True, though it should be noted that the flight capability of non ornithothoracine birds is questionable. At best, Balaur might better be called a glide less bird than a flightless bird.

[Gwangi]

That's a very ugly piece of artwork...

It sure is. Just look at those feet! Shameful that this passed as acceptable.

I love the discovery of any new feathered dinosaur (bird or otherwise) but this argument over the first true bird is really pointless. What is or is not a bird is arbitrary and any scientist that knows evolution also knows that things are not as black and white as "this is a bird" and "this is not a bird".

[amargasaurus cazaui]

I hoped i might interject a question here if I could perhaps. I am not much of a whiz at the early birdlike dinosaurs and theropods so much . I am more a basal ceratopsian and sauropod guy so I hoped you guys could enlighten me, a bit. I am not baiting an argument but actually truly do not understand...what are the issues with the animal as it was drawn? I ask this not to provoke argument, but rather because I myself would like to learn and understand better....Patrx or perhaps Zopteryx, anyone that can give some ideas why the drawing is so bad please? I really appreciate the insight and ideas in advance, thanks.

[tyrantqueen]

I hoped i might interject a question here if I could perhaps. I am not much of a whiz at the early birdlike dinosaurs and theropods so much . I am more a basal ceratopsian and sauropod guy so I hoped you guys could enlighten me, a bit. I am not baiting an argument but actually truly do not understand...what are the issues with the animal as it was drawn? I ask this not to provoke argument, but rather because I myself would like to learn and understand better....Patrx or perhaps Zopteryx, anyone that can give some ideas why the drawing is so bad please? I really appreciate the insight and ideas in advance, thanks.

I'll interject here, since I was the one who made the statement originally.

It could just be a matter of taste (art is subjective after all) However, to me, the posture of the legs looks very odd, like they are made of spaghetti, and very unnaturally bent. I should be able to see tendons in the lower part of the legs, but I can't. The feathers and body covering doesn't seem to "flow" with the body, they look pasted on.

TL;DR: It looks like a bad cgi model, and not a natural animal.

If you like the model, that's fine too

[Dinoguy2]

I hoped i might interject a question here if I could perhaps. I am not much of a whiz at the early birdlike dinosaurs and theropods so much . I am more a basal ceratopsian and sauropod guy so I hoped you guys could enlighten me, a bit. I am not baiting an argument but actually truly do not understand...what are the issues with the animal as it was drawn? I ask this not to provoke argument, but rather because I myself would like to learn and understand better....Patrx or perhaps Zopteryx, anyone that can give some ideas why the drawing is so bad please? I really appreciate the insight and ideas in advance, thanks.

To add on, a big problem with the feet is that it appears to be standing on tip-toe with no pad under the back of the toes to support its weight (as all birds have and we know theropods had based on footprints).

It also suffers from a systematic problem that still lurks in paleoart and is especially a problem for CGI models--drawing or rendering the body first *without* feathers and then adding feathers after. WHY? The underlying anatomy is invisible and irrelevant once you add realistic level of feathering, so it's a waste of time and effort. It's worse in CG models because feathers do not sit on the body like hair does, but most rendering programs only use hair. It obvious this thing is covered in fur. That body covering does not look like feathers. Theo nes that do look like feathers and were obviously rendered individually just stick out at almost random sharp angles, especially on the legs, and there is no transition--it's like the leg feathers sprout from the bone with no coverts or contour feathers.

Imagine doing a CG model of a chicken. Would you start by modeling this:


And then add white fur and random sticky-out feathers on the wing? Heck no. It would look awful. You'd start by rendering the whole profile WITH FEATHERS, like this:



And then add a little texture, as they did above.

Most CG modellers have yet to figure this out, and it doesn't help that they seem to be totally ignorant of bird anatomy. It's unfortunate that artists who are used to drawing dinosaurs, when switching to "modern" versions, make them "dinosaurs with feathers" instead of "feathered dinosaurs." There's a HUGE difference.

(end of rant )

[wings]

Though not often you see much features under the feathers. Sometimes it depends on the lighting and the amount that's been "puffed out".

These two not so much...





... a bit more puffed out...



...while this one; quite a bit more...



On the first two you can clearly see the protrusion of the wrists and some of the lower arm as seen on the second photo (see how the curvature of the body changed around the "shoulder" region(s) as indicated by the way the shadow is cast and how the light hits the area) however you don't see this on the last two photos. Area like the hips (like the tips of the iliac blades) is often covered by the primaries and secondaries so even if there are landmarks when the feather is not puffed out; you just won't see it even if it could be visible when not covered up. Since not all theropods have the ability to fold up their arms all the way so these "areas" could still be possibly be exposed when the feather is "sleeked down". Without knowing the underlying structures it would be difficult (it's not impossible but just a little tricky) to produce a convincing "sleeked down" version (or you can constantly stick with the puffed out version...).   

[amargasaurus cazaui]

My point was not so much that I liked or wanted to defend the painting as accurate at all TQ, but rather why it was not accurate and what those issues are, so I could understand them better and learn from .
     So the point being made with the feet would be they should be flat and placed similar to the method of stance a tyrannosaurus would employ..with heel and toes being placed to the ground in one motion?
     Very educational about the feathers for sure. After reading the comments and looking more closely at the legs I see how the larger feathers look odd , in how they are attached and aligned along the legs. Were the ba legs supposed to have held a wing as well and is this the artists attempt to portray a feature not generally seen in modern birds, or is there a more modern paralell that could have been drawn from to make them appear more....realistic?
  Thanks dinoguy and Wings and TQ for your thoughts, I knew the way it was standing just looked "odd" but I could not put my finger on it .