Pack hunting dinosaurs

[Metallisuchus]

Thanks Sharptooth, at least somebody gets what I'm saying.

To get back to the original point, the only true debate was whether or not there was pack-hunting among Dromies (or any other dinosaurs for that matter). There was recent evidence mentioned that I was previously unaware of about Deinonychus fighting over the Tenontosaurus, rather than them hunting cooperatively (you know - that infamous find that really got people talking about pack-hunting in the first place), but according to somebody else, that second theory has been debunked. I believe Gwangi knew that this other guy allegedly "debunked" the Deinonychus fighting each other theory, and I'm pretty sure Gwangi left that bit of information out (I could be wrong - I just don't feel like going back in the thread to even bother).

Regardless, that's just one find. I do not know if there is truly evidence supporting Gwangi's claim of Deinonychus fighting each other, but if there is, that still doesn't mean there wasn't pack-hunting. That's pretty much the gist of the debate, and it's come to all of this, lol.

[Dinoguy2]

For the record, there's a little about sauropods being r-selected vs. k-selected here, with cites: http://scienceblogs.com/tetrapodzoology/2011/05/sauropod_viviparity_meme.php

[Metallisuchus]

I don't recall that part about Bakker. The idea of ANY dinosaur giving birth to live young always sounded silly to me, as there have been discoveries of eggs from various species for a long time now.

Recently, there was a claim that some marine reptile gave birth to live young (I forget which type, maybe some kind of Mosasaur?), and I even have a hard time believing that.

As it stands right now, I am believing in the sea-turtle method.

[ZoPteryx]

Recently, there was a claim that some marine reptile gave birth to live young (I forget which type, maybe some kind of Mosasaur?), and I even have a hard time believing that.

I believe it was plesiosaurs in the news most recently, maybe elasmosaurs more specifically.  Although mosasaurs are thought have given live birth as well.

[Arioch]

Recently, there was a claim that some marine reptile gave birth to live young (I forget which type, maybe some kind of Mosasaur?), and I even have a hard time believing that.

As it stands right now, I am believing in the sea-turtle method.

??

There is direct evidence of viviparity in Ichthyosaurs and mosasaurs. And not precisely recent.

[Metallisuchus]

Recently, there was a claim that some marine reptile gave birth to live young (I forget which type, maybe some kind of Mosasaur?), and I even have a hard time believing that.

As it stands right now, I am believing in the sea-turtle method.

??

There is direct evidence of viviparity in Ichthyosaurs and mosasaurs. And not precisely recent.

What I heard was a VERY recent announcement on some science website. It was announced as a brand new discovery, and I don't think I even read the whole thing. I don't know what could account for "direct evidence", but then again, I've never really read much on marine reptiles. I can only vaguely recollect the article, and dismissed it entirely (mostly due to lack of interest). So yeah, there ya go, Arioch. But now that I think about it, some sharks give birth to live young, right? So I guess marine reptiles doing so isn't so hard to believe.

So what is this "direct evidence" in a nutshell? (Not denying that there is, just asking)

Oh, and to avoid confusion - the "sea turtle method" reference was to sauropods, not marine reptiles.

[Gwangi]

I know how you're getting information, just as I do. But I'm not just going to accept every claim made by a paleontologist either. A lot of these new claims need to be investigated, just as the old ones were. There are always new claims, and most of them are discredited within 5 years. This is why I stick to a lot of older theories and evidence. Really, I am very Bakker-derivative in my view of paleontology. Anyway, I'm skeptical when it comes to certain things, though not so stubborn as to dismiss possibilities.

I don't expect anyone to accept every claim and that wouldn't even be possible with the range of opinions on the subject. Claims do need to be investigated, that is what science is all about. Even we in our limited capacity can investigate claims through research.

I had a simple idea that just popped into my head about the possibility of sauropods using the cuckoo bird method which was not based on any evidence other than the fact that a modern species of 'dinosaur' uses this method, and I use the term 'evidence' lightly. I never even implied I believed in this, I just thought about it.

It just seemed out of place in a discussion regarding the actual evidence for or against parental care is all. I realize it was just speculation.

There IS no debate regarding sauropods.

Sure there is, that is what we were doing a couple pages back. Even the professionals debate these things.

I never took a stance, not at all. I am not aware of ANY REAL evidence of them abandoning their young, nor nurturing them into adulthood. As I stated twice already, the only way I see them abandoning their young is by the cuckoo method (which I don't find likely), or the sea-turtle method (which is probably the most believable). Now you said there is a bit of evidence that some sauropods laid such an abundance of eggs that the sea-turtle method is very likely. If that's true, then I'm certainly on board with the sea-turtle theory. But an abundance of eggs isn't solid proof of this. It would just help support the notion.

No one said there was solid proof of anything we've discussed in this entire thread. I'm only looking at the best evidence we have regardless on how fragmentary that evidence is. When it comes to animals that have been extinct for 65 million years that is all we really can do. There are no absolutes in science, we just follow the evidence.

The discussion isn't just about evidence. As I said, most of what we call 'evidence' is only 'supporting evidence', not 'definitive evidence', and that paleontology NEEDS people to think outside the box - to think of possibilities whether there is a shred of evidence or not. If there is no evidence to support an idea, we can think of ways to search for evidence which may lead to factual knowledge. I feel like you're not getting this - as if you have this completely different idea of what I'm about.

I actually do get it believe it or not, we're pretty much on the same page here. The difference between us is on what exactly we're doing in this thread. While you're casually talking dinosaur I was under the impression that a debate was going on.

To get back to the original point, the only true debate was whether or not there was pack-hunting among Dromies (or any other dinosaurs for that matter). There was recent evidence mentioned that I was previously unaware of about Deinonychus fighting over the Tenontosaurus, rather than them hunting cooperatively (you know - that infamous find that really got people talking about pack-hunting in the first place), but according to somebody else, that second theory has been debunked. I believe Gwangi knew that this other guy allegedly "debunked" the Deinonychus fighting each other theory, and I'm pretty sure Gwangi left that bit of information out (I could be wrong - I just don't feel like going back in the thread to even bother).

Whatever evidence you're talking about that counters the paper I posted I am not aware of it. I would hope that if anything you would know that I'm all about the evidence. I wouldn't deliberately ignore evidence that I didn't like, that is the exact thing I'm speaking out against. If you have knowledge of this recent study please share it because this is the first I've heard of it. I would very much like to read about it and reevaluate my opinion on the subject accordingly.

Regardless, that's just one find. I do not know if there is truly evidence supporting Gwangi's claim of Deinonychus fighting each other, but if there is, that still doesn't mean there wasn't pack-hunting. That's pretty much the gist of the debate, and it's come to all of this, lol.

For the record the claim against pack hunting it not my claim. It is a claim from a scientist I happen to agree with. There is evidence for the claim otherwise the paper I posted would not have been written. Among the evidence is a Deinonychus toe claw imbedded in the tail of another Deinonychus which could show conflict amongst the individuals. Read the paper, it is all quite interesting.

[Gwangi]

What I heard was a VERY recent announcement on some science website. It was announced as a brand new discovery, and I don't think I even read the whole thing. I don't know what could account for "direct evidence", but then again, I've never really read much on marine reptiles. I can only vaguely recollect the article, and dismissed it entirely (mostly due to lack of interest). So yeah, there ya go, Arioch. But now that I think about it, some sharks give birth to live young, right? So I guess marine reptiles doing so isn't so hard to believe.

So what is this "direct evidence" in a nutshell? (Not denying that there is, just asking)

Oh, and to avoid confusion - the "sea turtle method" reference was to sauropods, not marine reptiles.

In the case of Ichthyosaurs there are fossils of them with developing young inside and even giving birth. There are also fossils of mosasaurs with developing young as well. There are modern reptiles that also give live birth.

[Metallisuchus]

I know how you're getting information, just as I do. But I'm not just going to accept every claim made by a paleontologist either. A lot of these new claims need to be investigated, just as the old ones were. There are always new claims, and most of them are discredited within 5 years. This is why I stick to a lot of older theories and evidence. Really, I am very Bakker-derivative in my view of paleontology. Anyway, I'm skeptical when it comes to certain things, though not so stubborn as to dismiss possibilities.

I don't expect anyone to accept every claim and that wouldn't even be possible with the range of opinions on the subject. Claims do need to be investigated, that is what science is all about. Even we in our limited capacity can investigate claims through research.

I had a simple idea that just popped into my head about the possibility of sauropods using the cuckoo bird method which was not based on any evidence other than the fact that a modern species of 'dinosaur' uses this method, and I use the term 'evidence' lightly. I never even implied I believed in this, I just thought about it.

It just seemed out of place in a discussion regarding the actual evidence for or against parental care is all. I realize it was just speculation.

There IS no debate regarding sauropods.

Sure there is, that is what we were doing a couple pages back. Even the professionals debate these things.

I never took a stance, not at all. I am not aware of ANY REAL evidence of them abandoning their young, nor nurturing them into adulthood. As I stated twice already, the only way I see them abandoning their young is by the cuckoo method (which I don't find likely), or the sea-turtle method (which is probably the most believable). Now you said there is a bit of evidence that some sauropods laid such an abundance of eggs that the sea-turtle method is very likely. If that's true, then I'm certainly on board with the sea-turtle theory. But an abundance of eggs isn't solid proof of this. It would just help support the notion.

No one said there was solid proof of anything we've discussed in this entire thread. I'm only looking at the best evidence we have regardless on how fragmentary that evidence is. When it comes to animals that have been extinct for 65 million years that is all we really can do. There are no absolutes in science, we just follow the evidence.

The discussion isn't just about evidence. As I said, most of what we call 'evidence' is only 'supporting evidence', not 'definitive evidence', and that paleontology NEEDS people to think outside the box - to think of possibilities whether there is a shred of evidence or not. If there is no evidence to support an idea, we can think of ways to search for evidence which may lead to factual knowledge. I feel like you're not getting this - as if you have this completely different idea of what I'm about.

I actually do get it believe it or not, we're pretty much on the same page here. The difference between us is on what exactly we're doing in this thread. While you're casually talking dinosaur I was under the impression that a debate was going on.

To get back to the original point, the only true debate was whether or not there was pack-hunting among Dromies (or any other dinosaurs for that matter). There was recent evidence mentioned that I was previously unaware of about Deinonychus fighting over the Tenontosaurus, rather than them hunting cooperatively (you know - that infamous find that really got people talking about pack-hunting in the first place), but according to somebody else, that second theory has been debunked. I believe Gwangi knew that this other guy allegedly "debunked" the Deinonychus fighting each other theory, and I'm pretty sure Gwangi left that bit of information out (I could be wrong - I just don't feel like going back in the thread to even bother).

Whatever evidence you're talking about that counters the paper I posted I am not aware of it. I would hope that if anything you would know that I'm all about the evidence. I wouldn't deliberately ignore evidence that I didn't like, that is the exact thing I'm speaking out against. If you have knowledge of this recent study please share it because this is the first I've heard of it. I would very much like to read about it and reevaluate my opinion on the subject accordingly.

Regardless, that's just one find. I do not know if there is truly evidence supporting Gwangi's claim of Deinonychus fighting each other, but if there is, that still doesn't mean there wasn't pack-hunting. That's pretty much the gist of the debate, and it's come to all of this, lol.

For the record the claim against pack hunting it not my claim. It is a claim from a scientist I happen to agree with. There is evidence for the claim otherwise the paper I posted would not have been written. Among the evidence is a Deinonychus toe claw imbedded in the tail of another Deinonychus which could show conflict amongst the individuals. Read the paper, it is all quite interesting.

Okay then, what is the debate on sauropods as parents? Where are we disagreeing on this subject?

The thing you posted on the Deinonychus paper... I looked around a bit myself and I came across what I believe is the same article you posted, and in that same article (if it is indeed the same), it references a rebuttal by another paleontologist. Did you just leave that part out? The actual rebuttal itself sadly wasn't given - it was just mentioned that there was another guy who disputes that claim (the one you believe in).

I will admit, you have shaken my foundation a bit, regarding pack-hunting, and that's scientifically healthy. We should never be so sure. But I still stand my ground that I believe some therapods have hunted in packs/pairs at least once in a while, even if they did fight over the carcass afterwards.

[Metallisuchus]

What I heard was a VERY recent announcement on some science website. It was announced as a brand new discovery, and I don't think I even read the whole thing. I don't know what could account for "direct evidence", but then again, I've never really read much on marine reptiles. I can only vaguely recollect the article, and dismissed it entirely (mostly due to lack of interest). So yeah, there ya go, Arioch. But now that I think about it, some sharks give birth to live young, right? So I guess marine reptiles doing so isn't so hard to believe.

So what is this "direct evidence" in a nutshell? (Not denying that there is, just asking)

Oh, and to avoid confusion - the "sea turtle method" reference was to sauropods, not marine reptiles.

In the case of Ichthyosaurs there are fossils of them with developing young inside and even giving birth. There are also fossils of mosasaurs with developing young as well. There are modern reptiles that also give live birth.

Cool, thanks for the photo Gwangi.

[Sharptooth]

Yeah, that discovery show that, at least in that occasion, two or more Deinos fought viciously against eachother, like buzzards sometimes do even today.
But, and i have to say it, it doesn't necessarily means that some form of pack hunting wasn't present in the clade or even in D. Antihrropus; maybe those raptors did belong to two rival groups, maybe there was a famine and they became more vicious due to starvation... Oh well, you get my point.

About viviparity in sea reptiles, well, as Arioch said it's well documented for all the major groups (Ichtyos, Plesios and Mosasaurs); and i'd bet this means there was also some form of parental care, maybe like in whales...

[Gwangi]

Okay then, what is the debate on sauropods as parents? Where are we disagreeing on this subject?

Read back a few pages if you wish. It was several days ago at this point but I recall a discussion about parenting in dinosaurs. I said I didn't think sauropods took care of their young and you disagreed with me and even asked for the evidence. I gave you my best overview of the evidence and you came up with more ideas on why parental care was likely. Don't take that brief reiteration as an exact quote. Like I said, it was several days ago and my memory may be off. That is how the events unfolded as I currently see it without reading back a few pages. Please don't take offense if I've taken any of your statements out of context or misspoke about the events as they took place.

The thing you posted on the Deinonychus paper... I looked around a bit myself and I came across what I believe is the same article you posted, and in that same article (if it is indeed the same), it references a rebuttal by another paleontologist. Did you just leave that part out? The actual rebuttal itself sadly wasn't given - it was just mentioned that there was another guy who disputes that claim (the one you believe in).

It has been some time since I read that paper but if you're implying that that author himself acknowledged a challenge to this theory within the written paper I would not be surprised and don't see the relevance. I (and I'm sure he) is aware that there are paleontologists who disagree with his paper, there always are and that is a good thing. I didn't purposely leave anything out, I posted a paper that supported my argument and that it all. Like I said, if you have a recent paper supporting your notion of pack hunting that challenged the one I posted please share it as I would like to read it.

I will admit, you have shaken my foundation a bit, regarding pack-hunting, and that's scientifically healthy. We should never be so sure. But I still stand my ground that I believe some therapods have hunted in packs/pairs at least once in a while, even if they did fight over the carcass afterwards.

And I stand my ground that until good evidence is found for pack hunting I cannot allow myself to assume they did. I can fantasize about the possibility and speculate all I want but the evidence for now provides me with my view on the debate.

[Gwangi]

Yeah, that discovery show that, at least in that occasion, two or more Deinos fought viciously against eachother, like buzzards sometimes do even today.
But, and i have to say it, it doesn't necessarily means that some form of pack hunting wasn't present in the clade or even in D. Antihrropus; maybe those raptors did belong to two rival groups, maybe there was a famine and they became more vicious due to starvation... Oh well, you get my point.

Yes, maybe to all of those things. There are lots of maybes, any thought you can conceive of is a maybe. Maybe Deinonychus had an advanced culture and used telepathy to kill their prey? We don't know and we can speculate all day. If we want actual answers the fragmented fossil record and the scientific method will have to do for now. 

[DinoToyForum]

The recent news article about live birth was regarding the plesiosaur Polycotylus, a derived short-necked variety. Suffice to say, a certain forum admin was quoted in the BBC news article. I also blogged about it on my Plesiosaur Bites Blog. I won't go into details as it is waaaaay off topic.

[Gwangi]

The recent news article about live birth was regarding the plesiosaur Polycotylus, a derived short-necked variety. Suffice to say, a certain forum admin was quoted in the BBC news article. I also blogged about it on my Plesiosaur Bites Blog. I won't go into details as it is waaaaay off topic.

Probably more on topic than this thread was a couple days ago. Though I do suppose it has come back round again. Thanks for sharing that though, I wasn't aware of this.

[Sharptooth]

Yes, maybe to all of those things. There are lots of maybes, any thought you can conceive of is a maybe. Maybe Deinonychus had an advanced culture and used telepathy to kill their prey? We don't know and we can speculate all day. If we want actual answers the fragmented fossil record and the scientific method will have to do for now. 

Eh eh, guess you're right, sadly all we have for now are, as i always say, just glimpses of the ancient time...




... Maybe. 

[Metallisuchus]

Gwangi...

If you recall, I was the first one to mention the notion of the sea turtle method as the only way I can see them abandoning their young. I wasn't 'married' to my earlier idea of them being nurturing parents, I just said it's hard for me to imagine them just leaving their young behind to die unless the "sea turtle" theory is correct. I believe you (or somebody else) did provide a shred of evidence for this, so for now, I'm on board with that theory. So isn't there an agreement between us on that topic?

Okay, so the paper you posted was directly written by the researcher? My mistake then. What I read was an article ABOUT that paper, and in that article, it was mentioned that the particular paper/theory you speak of was "debunked". Debunked how? I do not know. The article didn't get into an specifics on that, unfortunately. I don't think we'll ever find evidence that Dromies DIDN'T hunt in packs - all we'll find is ways of discrediting evidence that they DID hunt in packs, if that makes sense...

Anyway, as I see it, we've reached our end for the debate unless something new is discovered. I'm rather enjoying the dinosaur figure aspect of this forum more than anything. And for the forum's sake, we should stick to the topics at hand more, lol.

[HD-man]

I hope you guys don't mind me posting in this thread given how old it is. It's just that, while some of my criticisms have already been mentioned here by others, I wanted to discuss them all at once.

1stly, some here have tried to define "pack hunting", but haven't actually done so (No offense meant; I'm just saying). Ellis et al. 1993 ( http://www.jstor.org/discover/10.2307/1312102?uid=3739952&uid=2&uid=4&uid=3739256&sid=21102524819193 ) neatly sorts out the various classes of social foraging. If you can't get past the paywall, the 1st 2 pages of Orellana & Rojas 2005 ( https://www.academia.edu/3513923/Possible_social_foraging_behavior_in_the_Red-backed_Hawk_Buteo_polyosoma_ ) sums them up. There's non-cooperative hunting (E.g. Mobbing), cooperative searching, pseudo-cooperative hunting, & true cooperative hunting (E.g. Pack hunting). & no, you don't have to hunt in a pack all the time to be a pack hunter (See the last 2 paragraphs: http://www.nytimes.com/1993/01/19/science/rabbits-beware-some-birds-of-prey-hunt-in-packs.html?pagewanted=all&src=pm ).

2ndly, some here have claimed that bird packs aren't comparable to wolf packs. However, based on what I've read, they are in terms of social structure & hunting tactics (E.g. See the Tudge quote for ground hornbills & this article for diurnal raptors: http://www.nytimes.com/1993/01/19/science/rabbits-beware-some-birds-of-prey-hunt-in-packs.html?pagewanted=all&src=pm ).

3rdly, some here have claimed that dromaeosaurids probably didn't have the intelligence for pack hunting. However, based on what I've read, they probably did (See the 1st Buchholtz quote). The same goes for other non-avian maniraptorans, but not for non-maniraptoran theropods (See the 2nd Buchholtz quote).

4thly, some here have cited Roach & Brinkman 2007 ( http://pds17.egloos.com/pds/201004/29/62/Theropod_Dinosaur.pdf ) when arguing against dromaeosaurids being pack hunters. However, many of the arguments made in said paper are very misleading/wrong ( http://jd-man.deviantart.com/journal/SD-Top-4-most-annoyingly-popular-dino-hypotheses-395469447 ). Li et al. 2007 shows how misleading/wrong 1 of those arguments is ("Roach and Brinkman...proposed that trackway data previously presented in support of gregarious nonavian theropods are perhaps better interpreted as coincidental instances of normally solitary individuals converging on a common point": http://cactus.dixie.edu/jharris/Dromaeopodus.pdf ).

5thly, some here have claimed that there's no evidence of dromaeosaurids being pack hunters. However, based on what I've read, there is: For 1, there are the dromaeosaurid bonebeds; I'm specifically referring to the "Four Raptor" site, which is more suggestive of a cooperative pack than an uncooperative mob; See Ostrom 1969 for the technical version ( http://peabody.yale.edu/sites/default/files/documents/scientific-publications/ypmB30_1969.pdf ) & Bakker's "Four Raptor" article for the popular version ( http://blog.hmns.org/2010/03/raptors-group-hunters-or-cannibals/ ); For another, there are the multiple shed teeth of dromaeosaurids found amongst the remains of their victims; I'm specifically referring to the Deinonychus/Tenontosaurus sites, which are even more suggestive; See Maxwell & Ostrom 1995 for the technical version ( http://www.jstor.org/stable/4523664 ) & Maxwell's 1999 article for the popular version ( http://www.naturalhistorymag.com/htmlsite/master.html?http://www.naturalhistorymag.com/htmlsite/1299/1299_feature.html ); For yet another, there are the dromaeosaurid trackways, which are the most suggestive of all; I'm specifically referring to the Dromaeopodus trackways in which "it is clear that the animals were not hunting at the time" ( http://scienceblogs.com/laelaps/2007/10/30/at-long-last-dromeosaur-tracks/ ); To quote Bakker, "Predators don't usually hang out in groups if they don't hunt together. Tigers are like this — they mostly hunt alone, and you don't see bunches of tigers lying around together. But lions are social predators. They hunt and raise their young and sleep and snore together" ( http://www.amazon.com/Raptor-Pack-Step-into-Reading-Step-5/dp/0375823034 ); The "raise their young...together" part is especially important b/c, to quote Orellana/Rojas, "cooperative hunting...is generally related to cooperative breeding"; Li et al. 2007 seems to agree ("The discovery of six parallel, closely spaced D. shandongensis trackways provides compelling, independent evidence for at least occasional..."pack" or family group...behavior in the track-making animals, comparable to what has been demonstrated in other dinosaurs": http://cactus.dixie.edu/jharris/Dromaeopodus.pdf ).

6thly, I'm not saying that all dromaeosaurids were definitely pack hunters, just that some eudromaeosaurs were probably pack hunters. I also concede that, among pack-hunting eudromaeosaurs, pair hunting was probably much more common than 3+ member hunting.

Lastly, while ants are technically true cooperative hunters by definition (See the 1st page of Ellis et al. 1993), their true cooperative hunting is different from that of vertebrates in that it's innate (as opposed to learned), & is thus considered a lower order of behavior than that of pack-hunting vertebrates (See the Stevens quote). If you want, you can do what I do & refer to true cooperative invertebrates as "swarm hunters" in reference to their "swarm intelligence".

Many thanks in advance for hearing me out. I hope I was able to help.

Quoting Tudge ( http://www.amazon.com/Bird-Natural-History-Birds-Where/dp/B007K4GP1W ):

The sociality that is encouraged by the diet tends to spill over into all aspects of life. So it is that hornbills are fruit eaters and also, as we will see in Chapter 7, are outstandingly social breeders, with various kinds of social arrangements. But also among hornbills we see an interesting twist—where the innate sociality has in turn become adapted to a quite different kind of feeding. For among the biggest of all hornbills, and in various ways distinct from the rest, are the two species of ground-hornbills from Africa. Ground-hornbills are not mere fruit eaters: they are formidable predators. The beak is like an icepick. They can hack their way into a tortoise. The Northern species is among the biggest of all avian predators. The ancestors of ground-hornbills were presumably fruit eaters, and that, perhaps, is how they first evolved their sociality. Now, as predators, they hunt in packs. Typically they chase some hapless creature like a hare into a bush and then some act as beaters while others lie in wait and deliver the coup de grace. The packs are usually family groups. They can be seen as strategic predators like wolves or perhaps as problem families, terrorizing the neighborhood.

Quoting Buchholtz ( http://www.amazon.com/Complete-Dinosaur-Second-Life-Past/dp/0253357012 ):

Endocasts of small coelurosaurs (Russell 1969, 1972; Colbert and Russell 1969; Kundrát 2007) display a strikingly different anatomical pattern (Fig. 10.6). They retain details of brain anatomy and roofing bone sutures on their surfaces, suggesting that the brain filled the braincase nearly completely. Brain flexures are minimal and olfactory bulbs are small, indicating that smell was not a dominant sense. Cerebral hemispheres are separable, convex, and expanded laterally and/or posteriorly (Kundrát 2007), suggesting an active intelligence. The large optic lobes are visible either dorsally or displaced laterally by the large cerebrum, as in living birds. Russell (1969) associated the large optic lobes with large eyes and binocular vision, and it is likely that sight was the dominant sense. Kundrát (2007) described an expanded cerebellum with presumptive cerebellar folia among the avianlike characters of the oviraptorid theropod Conchoraptor, inferring excellent balance and coordination.
Encephalization quotients of small coelurosaurs vary with predictions of body mass and percentage of braincase fill, but even conservatively, they are far higher than those of any other dinosaur group, overlapping those of living birds (Hopson 1977; Kundrát 2007). Larsson et al. (2000) estimated cerebral volumes by superimposing ellipsoids on endocasts with surficial indications of cerebral extent. Their data suggest at least three stages of increase of relative cerebral size to total brain size over a period of only 40 million years: of coelurosaurs over allosaurs, of Archaeopteryx over coelurosaurs, and of ornithurine birds over Archaeopteryx. The high encephalization values of small coelurosaurs indicate an active, complex, and social lifestyle that agrees well with their frequent interpretation as pack hunters.

Quoting Buchholtz ( http://www.amazon.com/Complete-Dinosaur-Second-Life-Past/dp/0253357012 ):

Brain anatomy in theropods is relatively well known and falls into two distinct anatomical groups, suggesting different dominant sensory modalities and lifestyles. Allosaurids and large coelurosaurs retain primitive endocast shape and distinct cerebral and pontine flexures (Fig. 10.2). The optic tectum is obscured and must have been small. The cerebral hemispheres are not separable and show only modest convexity. The prediction of extremely large olfactory bulbs in Tyrannosaurus rex (Brochu 2000) has been scaled downward, but it still seems likely that smell was a dominant sense (Rogers 1998, 1999; Stokstad 2005; Saveliev and Alifanov 2007). Rogers (1998, 1999) described the vestibular apparatus of Allosaurus fragilis, which more closely resembles that of crocodylians than that of lizards, turtles, or birds. He used semicircular canal orientation to suggest that Allosaurus held its head at or very slightly (≤10 degrees) inclined to the horizontal. Burish et al. (2004) included endocranial casts of Tyrannosaurus, Allosaurus, and Carcharodontosaurus in an analysis of relative telencephalic (~cerebral) size and behavior in birds. Their data indicate values for theropods at or below the range of living reptiles, and predict low social complexity.

Quoting Stevens ( http://www.nytimes.com/1993/01/19/science/rabbits-beware-some-birds-of-prey-hunt-in-packs.html?pagewanted=all&src=pm ):

On the other hand, raptor teamwork appears to signify a higher order of behavior than the cooperative hunting of spiders and ants, in whom it is genetically preprogrammed.
Dr. Ellis has spent months observing the behavior of golden eagles, and he says, "It's hard for me to imagine that they hadn't learned from their mistakes early on and were profiting from that learning, which means they're intelligent rather than practicing something innate." All of this, he says, is grist for further investigation -- a daunting task, given the difficulty of studying raptors.

[Dinoguy2]

Lastly, some here have asked whether ants are pack hunters. Yes, they are,

This is the problem, the definition of pack hunting. If you define it so broadly as it includes the behavior of ants, then basically everything living is a pack hunter and the term becomes meaningless.

Most people restrict pack hunting to highly social, human-like coordinated efforts as seen in some predatory mammals and a couple of bird species.

You equate "true cooperative hunting" with "pack hunting" but I and most biologists would disagree there. The word "pack" carries the meaning of a social order, relative social stability, hierarchy, etc. outside of a given hunt (i.e. a wolf pack). True cooperative hunting does not necessarily include all these things. It is entirely possible for dromaeosaurs to have been true cooperative hunters but not lived in packs. A pack is something you live in your whole life, basically, not something that forms for a hunt. That's called a group.

Something supporters of dromaeosaur cooperative hunting of any kind need to ask themselves is, not does the evidence support this, but does the evidence support this, BY FAR, beyond any of the alternate possible explanations. If the answer is no, then we need to agree that

1. Dromaeosaur cooperative hunting is definitely one possible interpretation of the evidence.
2. Because we're doing science, not science fiction, we can't say one way or the other that it ever actually happened, given current evidence.
3. It may not be possible to ever ay it actually happened without a time machine.
4. It's also not possible to say it NEVER actually happened, but so what? his is science, not "that would be awesome" wishful thinking. We're here to figure out ways to disprove hypotheses, not figure out what is physically or biologically plausible.

[HD-man]

Lastly, some here have asked whether ants are pack hunters. Yes, they are,

This is the problem, the definition of pack hunting. If you define it so broadly as it includes the behavior of ants, then basically everything living is a pack hunter and the term becomes meaningless.

Correct me if I'm wrong, but from the looks of it, you didn't read the definition of "pack-hunting" or the explanation of how ants & vertebrates differ, both of which were included in my previous post. For future reference, I've included both below, the former in the Orellana/Rojas quote & the latter in the 1st Stevens quote. & again, you don't have to hunt in a pack all the time to be a pack hunter (See the 2nd Stevens quote). Even wolves don't hunt in packs all the time ("In summer, when wolves hunt singly or in small groups, caching appears to be an important behavior...that helps secure excess food left from large prey or reduce loss to scavengers and maggots": http://www.amazon.com/Wolves-Behavior-Conservation-David-Mech/dp/0226516970/ref=sr_1_1?s=books&ie=UTF8&qid=1375750380&sr=1-1 ).

Quoting Orellana/Rojas  (See the 1st 2 pages: http://www.ibiologia.unam.mx/links/neo/revista/Volumenes%2016-17/16-2/ON%20(16)%20271-276.pdf ):

Cooper- ative hunting, in contrast, is characterized by a clear division of labor which enhances success of prey capture; prey are shared according to some social order (e.g., dominance, hierarchy)...and coordinating signals may be used (Bed- narz 1988a, Ellis et al. 1993, Coulson & Coul- son 1995). Cooperative hunting is executed by pairs, family groups, or sibling groups, and is generally related to cooperative breeding (Bednarz 1988a, 1988b). Because of the diffi- culty of obtaining quantitative data on free- ranging birds, the occurrence of social forag- ing in diurnal raptors could be underesti- mated (Ellis et al. 1993).

Quoting Stevens ( http://www.nytimes.com/1993/01/19/science/rabbits-beware-some-birds-of-prey-hunt-in-packs.html?pagewanted=all&src=pm ):

On the other hand, raptor teamwork appears to signify a higher order of behavior than the cooperative hunting of spiders and ants, in whom it is genetically preprogrammed.

Dr. Ellis has spent months observing the behavior of golden eagles, and he says, "It's hard for me to imagine that they hadn't learned from their mistakes early on and were profiting from that learning, which means they're intelligent rather than practicing something innate." All of this, he says, is grist for further investigation -- a daunting task, given the difficulty of studying raptors.

Quoting Stevens ( http://www.nytimes.com/1993/01/19/science/rabbits-beware-some-birds-of-prey-hunt-in-packs.html?pagewanted=all&src=pm ):

Raptors may use coordinated tactics only when solitary hunting does not provide enough food or is too difficult. Harris's hawks, for instance, use them only in winter, when a shortage of smaller quarry like small birds forces them to go after bigger game like jack rabbits, which are several times the size of a hawk.

Dr. Ellis and his colleagues speculate that when raptors hunt alone, they will not even try to capture prey that they know can be captured only through teamwork; it is not worth the expenditure of energy. But bigger game or the quicker capture resulting from group efforts can make the expenditure worthwhile.