Giant New Four-winged Maniraptoran

[Gwangi]

changyuraptor was almost certainly a glider, the extend of feathering on the legs would have been a major handicap otherwise

Are you sure it would have been a handicap? Many birds with long tails or long feathers on their legs (eagles, turkeys, peafowl etc) don't have a problem walking, and there is always the possibility that they would have been folded up. Feathers can't stop something from being able to walk; the feathers being dragged along the ground (if they were not folded up somehow) get damaged and tattered, but don't make much difference to the walking ability. It is only a problem if the leg feathers are important for survival which, if Changyupraptor was a ground animal, they would not. Maybe they were for display.

All the birds you mention are still excellent fliers and can simply take off at a moments notice, I doubt Changyuraptor could do that. Long tail feathers are really not a good analogy for feathers on the legs. Peafowl and turkeys can still move about fairly uninhibited with their tails more or less held up off the ground. Even the feathers on the legs of an eagle don't really compare to the long stiff feathers on Microraptor.

That is a good point. However, I was more referring to the fact that peafowl still drag their tails along the ground even though their tails get damaged, and don't really seem to 'care' about their feathers getting frayed and damaged. Changyuraptor would not have avoided walking if it damaged their feathers. Feathers can grow back, and being able to walk is more important than keeping their hindwings safe (especially if they were not used for flying and were instead used for  display or something.) The only way feathers on the hindlimbs would impair an animal's ability to walk would be if they were so stiff that they could not bend at all, which is a feature that even stiff flight feathers do not have.

Oh I'm sure Changyuraptor could walk and I agree with you on that. It seems to me that this is an animal that would have avoided extended periods on the ground. Push come to shove the feathers would get in the way I think if a predator was in pursuit, and I don't think it was as capable at flight as modern birds.

[HD-man]

Those could just be poorly preserved,

Probably not, given that both fossils preserve 1) a nearly complete set of hind limbs, & 2) other feather types near the upper legs, but nothing near the lower legs.

because one of those two species we know for sure did have them.

Which species & based on what fossils?

[Balaur]

Not all microraptorians had leg feathers. Tianyuraptor did not have the wing leg feathers.

[Yutyrannus]

because one of those two species we know for sure did have them.

Which species & based on what fossils?

Microraptor zhaoianus and based on most fossils of it.

Not all microraptorians had leg feathers. Tianyuraptor did not have the wing leg feathers.

That's true, but I still think at least some eudromaeosaurs had them.

[HD-man]

Microraptor zhaoianus and based on most fossils of it.

Sources? AFAIK, only 3 specimens have been described & only 1 of them preserve feathers. Yeah, I could be wrong, but you have to provide your sources & whatever evidence they have.

[Yutyrannus]

Microraptor zhaoianus and based on most fossils of it.

Sources? AFAIK, only 3 specimens have been described & only 1 of them preserve feathers. Yeah, I could be wrong, but you have to provide your sources & whatever evidence they have.

Well, if one of them has the feathers than all of them do, it's the same species.

Oh, and also:
http://upload.wikimedia.org/wikipedia/commons/a/af/Microraptor_gui_holotype.png
http://www.jsg.utexas.edu/news/files/02microraptor-fossil2-sm.jpg

[Balaur]

Microraptor zhaoianus and based on most fossils of it.

Sources? AFAIK, only 3 specimens have been described & only 1 of them preserve feathers. Yeah, I could be wrong, but you have to provide your sources & whatever evidence they have.

Well, if one of them has the feathers than all of them do, it's the same species.

Oh, and also:
http://upload.wikimedia.org/wikipedia/commons/a/af/Microraptor_gui_holotype.png
http://www.jsg.utexas.edu/news/files/02microraptor-fossil2-sm.jpg

You're talking about Microraptor gui. I don't think you're addressing Microrsptor zhaoinaus.

[Yutyrannus]

As far as I know M. gui was sunk into M. zhaoianus. Also, the second one is M. zhaoianus for sure.

"Subsequent studies (and more specimens of Microraptor) have shown that the features used to distinguish Cryptovolans are not unique, but are present to varying degrees across various specimens. In a review by Phil Senter and colleagues in 2004, the scientists suggested that all these features represented individual variation across various age groups of a single Microraptor species, making the name Cryptovolans pauli and Microraptor gui junior synonyms of Microraptor zhaoianus"

EDIT: Also, if M. gui is separate and it has the leg-wings as well that just proves my point even further.

[Yutyrannus]

And...
http://farm4.static.flickr.com/3446/3954522095_97049f64fa.jpg
http://1.bp.blogspot.com/-UZf-m_UgB0U/TnNOfj2bSqI/AAAAAAAABX8/xqnq4D5joWM/s1600/anchiornis_robert_clark.png
http://upload.wikimedia.org/wikipedia/commons/1/15/Vog1h.jpg

EDIT: And more:
http://images.nationalgeographic.com/wpf/media-live/photos/000/816/cache/four-winged-dino-fossil_81670_600x450.jpg
http://a57.foxnews.com/global.fncstatic.com/static/managed/img/Scitech/876/493/four-winged-bird-foot.jpg?ve=1&tl=1

Do you need any more evidence than that ?

[HD-man]

Well, if one of them has the feathers than all of them do, it's the same species.

Your missing the point (which isn't about whether M. zhaoianus had feathers, but whether it had hind limb primaries): The 1 feathered specimen of M. zhaoianus preserves 1) a nearly complete set of hind limbs, & 2) other feather types near the upper legs, but nothing near the lower legs.

As far as I know M. gui was sunk into M. zhaoianus.

According to some, yes, but not to most (E.g. See "Description": http://www.ivpp.ac.cn/qt/papers/201403/P020140313585351282162.pdf ).

Also, the second one is M. zhaoianus for sure.

Not really. Last I checked, it's been referred to either M. gui or no particular species ( http://www.nature.com/ncomms/2013/130918/ncomms3489/fig_tab/ncomms3489_F5.html ).

EDIT: Also, if M. gui is separate and it has the leg-wings as well that just proves my point even further.

How do you figure that? Correct me if I'm wrong, but I'm guessing that you're arguing that every species in the Microraptor genus had hind limb primaries based on M. gui. If that's the case, then your argument makes no sense (No offense). That's like arguing that every species in the Panthera genus had a mane based on P. leo.

[Yutyrannus]

Well, if one of them has the feathers than all of them do, it's the same species.

Your missing the point (which isn't about whether M. zhaoianus had feathers, but whether it had hind limb primaries): The 1 feathered specimen of M. zhaoianus preserves 1) a nearly complete set of hind limbs, & 2) other feather types near the upper legs, but nothing near the lower legs.

No, I'm saying that if one individual of the species has leg wings, then the entire species does. It's just common sense, like how all male lions have manes.

How do you figure that? Correct me if I'm wrong, but I'm guessing that you're arguing that every species in the Microraptor genus had hind limb primaries based on M. gui. If that's the case, then your argument makes no sense (No offense). That's like arguing that every species in the Panthera genus had a mane based on P. leo.

I'm trying to say that leg-wings were a common trait throughout paravians, not that just Microraptor had them. As I posted already, Microraptor zhaoianus, M. gui, Anchiornis, Archaeopteryx, Changyuraptor, as well as some early birds had them. This indicates that it is a common trait throughout paraves, I'm not saying that all paraves had them just that many did.

[Balaur]

Species can vary wildly. I am not sure if all Microraptor species had leg wings, but I wouldn't be surprised if it didn't. That one specimen could be a male, and females lacks leg wings, or is a subspecies.

[Yutyrannus]

True, it could. Although since the leg-wings seem to aid in gliding, it wouldn't make much sense that females lack them. Besides I'm not trying to prove that all Microraptor had them, but that many paraves (even ones that don't glide) likely had them.

Again, I post these:
http://upload.wikimedia.org/wikipedia/commons/a/af/Microraptor_gui_holotype.png
http://www.jsg.utexas.edu/news/files/02microraptor-fossil2-sm.jpg
http://farm4.static.flickr.com/3446/3954522095_97049f64fa.jpg
http://1.bp.blogspot.com/-UZf-m_UgB0U/TnNOfj2bSqI/AAAAAAAABX8/xqnq4D5joWM/s1600/anchiornis_robert_clark.png
http://upload.wikimedia.org/wikipedia/commons/1/15/Vog1h.jpg
http://images.nationalgeographic.com/wpf/media-live/photos/000/816/cache/four-winged-dino-fossil_81670_600x450.jpg
http://a57.foxnews.com/global.fncstatic.com/static/managed/img/Scitech/876/493/four-winged-bird-foot.jpg?ve=1&tl=1

[HD-man]

I'm trying to say that leg-wings were a common trait throughout paravians, not that just Microraptor had them. As I posted already, Microraptor zhaoianus, M. gui, Anchiornis, Archaeopteryx, Changyuraptor, as well as some early birds had them. This indicates that it is a common trait throughout paraves, I'm not saying that all paraves had them just that many did.

& I'm trying to say that, as indicated by the fossil evidence, not all microraptorines (let alone all dromaeosaurids) had hind limb PRIMARIES. That's all I've been trying to say.

BTW, of all the paravians you've listed, only M. gui & Changyuraptor are known to have had hind limb PRIMARIES. The others had other feather types on their hind limbs, but not PRIMARIES.

[Yutyrannus]

I'm trying to say that leg-wings were a common trait throughout paravians, not that just Microraptor had them. As I posted already, Microraptor zhaoianus, M. gui, Anchiornis, Archaeopteryx, Changyuraptor, as well as some early birds had them. This indicates that it is a common trait throughout paraves, I'm not saying that all paraves had them just that many did.

& I'm trying to say that, as indicated by the fossil evidence, not all microraptorines (let alone all dromaeosaurids) had hind limb PRIMARIES. That's all I've been trying to say.

BTW, of all the paravians you've listed, only M. gui & Changyuraptor are known to have had hind limb PRIMARIES. The others had other feather types on their hind limbs, but not PRIMARIES.

All of the one's I listed have them (except maybe Archaeopteryx, it's hard to tell from the picture ). Anchiornis, Microraptor gui, whatever that other Microraptor species is, Changyuraptor have hind limb primaries. And again I have to repeat myself, I'm not trying to say that all microraptorines had them, just that MANY or MOST paravians had them. There is no reason not to think so, only to think that not ALL of them did which is not what I'm trying to say. Now do you get what I'm trying to say?

EDIT: And by the way, very few species have evidence against having these "leg-wings", so until there is evidence otherwise it should be assumed that they had them.

[stargatedalek]

Species can vary wildly. I am not sure if all Microraptor species had leg wings, but I wouldn't be surprised if it didn't. That one specimen could be a male, and females lacks leg wings, or is a subspecies.

they serve a use in locomotion, there is no chance that this sort of feature could be gender dimorphic

[Yutyrannus]

Species can vary wildly. I am not sure if all Microraptor species had leg wings, but I wouldn't be surprised if it didn't. That one specimen could be a male, and females lacks leg wings, or is a subspecies.

they serve a use in locomotion, there is no chance that this sort of feature could be gender dimorphic

Well, there is a change, but it's highly unlikely.

[HD-man]

All of the one's I listed have them (except maybe Archaeopteryx, it's hard to tell from the picture ). Anchiornis, Microraptor gui, whatever that other Microraptor species is, Changyuraptor have hind limb primaries.

M. gui & Changyuraptor are known to have had hind limb primaries, but the others aren't. I've already covered the 1 feathered specimen of M. zhaoianus (which, again, preserves [1] a nearly complete set of hind limbs, & [2] smaller/weaker feather types near the upper legs, but NOTHING near the lower legs). As indicated by the Yong quote, the others (E.g. Archaeopteryx, Anchiornis, etc) are known to have had smaller/weaker feather types on their hind limbs, but not primaries.

Quoting Yong ( http://phenomena.nationalgeographic.com/2013/03/14/the-rise-and-fall-of-four-winged-birds/ ):

Habib thinks that the long asymmetric leg feathers of Microraptor probably did play some role in gliding or flying, but the smaller plumes of other baggy-legged species "might have merely been there because of a developmental quirk". If some genes are producing large feathers on the front limbs, "it might not take much to tweak a set onto the hind limbs too," he says.

[stargatedalek]

Species can vary wildly. I am not sure if all Microraptor species had leg wings, but I wouldn't be surprised if it didn't. That one specimen could be a male, and females lacks leg wings, or is a subspecies.

they serve a use in locomotion, there is no chance that this sort of feature could be gender dimorphic

Well, there is a change, but it's highly unlikely.

extremely unlikely, it would completely reshape the way animal behavior is understood


@ I used parenthesis on "primary" for a reason, that being by primary I was referring to "large feathers that look like wings" not necessarily asymmetrical feathers

[Balaur]

Species can vary wildly. I am not sure if all Microraptor species had leg wings, but I wouldn't be surprised if it didn't. That one specimen could be a male, and females lacks leg wings, or is a subspecies.

they serve a use in locomotion, there is no chance that this sort of feature could be gender dimorphic

Well, there is a change, but it's highly unlikely.

extremely unlikely, it would completely reshape the way animal behavior is understood


@ I used parenthesis on "primary" for a reason, that being by primary I was referring to "large feathers that look like wings" not necessarily asymmetrical feathers

It was just a thought of mine. Should have thought more about it at the time, as now I see it is very likely implausible.