2 questions...

[Sharptooth]

I see, i see... I admit that considering pterosaurs "dinosaurs" (in a very simplified way, of course) is fascinating, though...   

[Gwangi]

I see, i see... I admit that considering pterosaurs "dinosaurs" (in a very simplified way, of course) is fascinating, though...   

Dinosaurs are classified as such because they are united by a set of characteristics that other animals though related don't have. Chief among these would be features like the "S" shaped neck and upright gait/position of the legs. There are other features that unite dinosaurs together that are a bit more technical and I couldn't tell you off hand but pterosaurs lack these characteristics and so cannot be classified as dinosaurs without changing the definition of dinosaur but why do that? Pterosaurs are still dinosaur relatives and united with them because of characteristics that they both share, we already have a name for that classification. Even if you were to re-classify pterosaurs as dinosaurs you would still need a way to distinguish the two and would need yet another classification for that. Pterosaurs also don't fit into either of the two groups within Dinosauria so there isn't even a place to put them.

[Metallisuchus]

And what if... (not saying it's how i see it, bear in mind)... pterosaurs are just another type of dinosaurs as Bakker suggested in '86?

I don't think anyone takes that idea seriously anymore, if they ever did. You'd have to redefine the Dinosauria to be much broader...and a name for such a clade already exists.

I actually re-read that chapter recently. I was shocked - I don't remember that part, and I read his book a few times in the past (keeping in mind I was about 12 the first time). The notion kind of blew my mind, especially coming from him. By the time I was done, I felt as if he was just throwing the word 'dinosauria' around to include everything that descended from that particular genus (I forget which it is).

[Metallisuchus]

And what if... (not saying it's how i see it, bear in mind)... pterosaurs are just another type of dinosaurs as Bakker suggested in '86?

No. Absolutely not.  If a conversation is going to be taken seriously, I wouldn't recommend invoking Bakker hypotheses.  For every hit he had (keeping in mind, most of those were really other people's work that he was just much better at publicizing) there is a lot of way-out insanity in his 'theories'.

This article has a pretty succinct explanation of why it couldn't work (or why we would need to expand the meaning of 'dinosaur' to ridiculous extremes, I suppose):
http://blogs.smithsonianmag.com/dinosaur/2010/11/why-a-pterosaur-is-not-a-dinosaur/

Out of curiosity, what other theories of his were 'insane', as you put it? I do agree that Bakker seems to get credit for a lot of what his mentor (Ostrom) had already pioneered, but I wouldn't disregard Bakker as a paleontologist. Some of the greatest minds in paleontology (or science in general) had a lot of wacky theories, in retrospect. What was that saying about 'finding 1,000 ways NOT to do something'?

[SBell]

And what if... (not saying it's how i see it, bear in mind)... pterosaurs are just another type of dinosaurs as Bakker suggested in '86?

No. Absolutely not.  If a conversation is going to be taken seriously, I wouldn't recommend invoking Bakker hypotheses.  For every hit he had (keeping in mind, most of those were really other people's work that he was just much better at publicizing) there is a lot of way-out insanity in his 'theories'.

This article has a pretty succinct explanation of why it couldn't work (or why we would need to expand the meaning of 'dinosaur' to ridiculous extremes, I suppose):
http://blogs.smithsonianmag.com/dinosaur/2010/11/why-a-pterosaur-is-not-a-dinosaur/

Out of curiosity, what other theories of his were 'insane', as you put it? I do agree that Bakker seems to get credit for a lot of what his mentor (Ostrom) had already pioneered, but I wouldn't disregard Bakker as a paleontologist. Some of the greatest minds in paleontology (or science in general) had a lot of wacky theories, in retrospect. What was that saying about 'finding 1,000 ways NOT to do something'?

Perhaps I over-stated his wackiness. What I probably can't overstate is that 1) He stood on the shoulders of a giant (Ostrom) and mainstreamed warm-blooded dinosaurs and 2) Not manyy of his other hypotheses have ever really taken off--either within the public, or in the scientific community.  Such as a dinosaur 'family' that includes pterosaurs.

So in fact, he made important contributions. But in general, if someone wants to bring up a 'theory' of his as some sort of argument for scientific validity for an idea, it would be wise to check if there has ever been any further support.

And Stephen J Gould once said, in regard to science-mavericks being right because it happens sometimes (in general, a response given by someone with an outlandish hypothesis that has neither support nor evidence, but doesn't want to back down, and so claim that it's their genius that isn't being appreciated, or some such thing), "you not only have to be persecuted; you also have to be right".

[Metallisuchus]

I know he disputed dinosaurs like Parasaurolophus being an excellent swimmer, though I'm not sure if he was the first to do so. I can't help but love Bakker though.

[SBell]

I know he disputed dinosaurs like Parasaurolophus being an excellent swimmer, though I'm not sure if he was the first to do so. I can't help but love Bakker though.

Bakker did a lot of good things.  He often championed ideas that had merit, but were poorly understood or researched.  He certainly did a lot to make himself a public figure.  In part, because he came from a background as an evangelical minister, which made him an excellent spokesperson when he started discussing dino/science issues. It gave him the skills of oration in a field that was getting pretty stagnant at the time.

But from the paleontologists I've known, he is not regarded as...highly...as the public overall.  Unfortunately, he kind of likes/d the spotlight, and hence the occasionally silly ideas once in a while--ideas that get press, but don't do much for the science or his legacy.

[Gwangi]

I know he disputed dinosaurs like Parasaurolophus being an excellent swimmer, though I'm not sure if he was the first to do so. I can't help but love Bakker though.

He is easy to love, very charismatic and unlike many other academics able to generate interest in topics that would otherwise seem boring (though dinosaurs are seldom boring). I think he suffers from the same issues as Jack Horner, he is a media superstar where dinosaurs are concerned. He makes his living off of being different from everyone else and so he postulates these extreme theories that have little to back them up. Things like pack hunting Deinonychus (sorry), live birth for sauropods, pterosaurs being dinosaurs to name a few. He has done a lot of work to change how we view dinosaurs but most of it is certainly on the extreme end of things. He represents the other end of the spectrum from the old ways dinosaurs were portrayed. I think in his effort to change how we view dinosaurs he went a bit far out there. I love the guy too, he is the poster child for paleontology and some of his theories are sound. I just wonder if he has spent too much time in the limelight and not in the field (or lab).
On another note his theory regarding dinosaur extinction sounds like total BS to me. He theorizes (or used to) that disease killed off the dinosaurs (it is mentioned in JP) and I used to buy into it myself. I find it strange that he would think disease would wipe out an entire group of animals (save for birds somehow) when he considered them so adaptable and successful. Seems counter intuitive.

[Sharptooth]

I see, i see... I admit that considering pterosaurs "dinosaurs" (in a very simplified way, of course) is fascinating, though...   

Dinosaurs are classified as such because they are united by a set of characteristics that other animals though related don't have. Chief among these would be features like the "S" shaped neck and upright gait/position of the legs. There are other features that unite dinosaurs together that are a bit more technical and I couldn't tell you off hand but pterosaurs lack these characteristics and so cannot be classified as dinosaurs without changing the definition of dinosaur but why do that? Pterosaurs are still dinosaur relatives and united with them because of characteristics that they both share, we already have a name for that classification. Even if you were to re-classify pterosaurs as dinosaurs you would still need a way to distinguish the two and would need yet another classification for that. Pterosaurs also don't fit into either of the two groups within Dinosauria so there isn't even a place to put them.

I know this stuff, i was just playing with the alternatives 

About Bakker, of course he pulled out some wacky and probably wrong theories (like every other paleontologist, bear in mind), but at least he's way more sympathetic than Horner; recreating dinosaurs using modern bird embryos... Really, he helped paleontology A LOT in the past, but now it seems he's just "scraping the barrel" with this horrible (and utterly useless) project 

[Metallisuchus]

I know he disputed dinosaurs like Parasaurolophus being an excellent swimmer, though I'm not sure if he was the first to do so. I can't help but love Bakker though.

He is easy to love, very charismatic and unlike many other academics able to generate interest in topics that would otherwise seem boring (though dinosaurs are seldom boring). I think he suffers from the same issues as Jack Horner, he is a media superstar where dinosaurs are concerned. He makes his living off of being different from everyone else and so he postulates these extreme theories that have little to back them up. Things like pack hunting Deinonychus (sorry), live birth for sauropods, pterosaurs being dinosaurs to name a few. He has done a lot of work to change how we view dinosaurs but most of it is certainly on the extreme end of things. He represents the other end of the spectrum from the old ways dinosaurs were portrayed. I think in his effort to change how we view dinosaurs he went a bit far out there. I love the guy too, he is the poster child for paleontology and some of his theories are sound. I just wonder if he has spent too much time in the limelight and not in the field (or lab).
On another note his theory regarding dinosaur extinction sounds like total BS to me. He theorizes (or used to) that disease killed off the dinosaurs (it is mentioned in JP) and I used to buy into it myself. I find it strange that he would think disease would wipe out an entire group of animals (save for birds somehow) when he considered them so adaptable and successful. Seems counter intuitive.

We just can't avoid the notion of pack-hunting can we? Lol. But it's not like it was an original Bakker idea. I think he was just really taking what Ostrom did, and trying to take it as far as he could - trying to really prove that his teacher was right. And yeah, Bakker is the rock star of paleontology, but the guy has done so much to change the old view of dinosaurs. Extinction to me is still an open book. I think it was a combination of things, and dinosaurs were becoming scarce towards the end of the Cretaceous anyway.

I touched on this before - but science needs 'wacky theories' just to shake things up. It's funny, but I think Bakker even says this in his book. He's also not insecure like most scientists - he loves to prove himself wrong just so he can find out what's right. At one point, he believed dinosaurs were an unnatural group but he was happy to disprove that eventually.

[Horridus]

At one point, he believed dinosaurs were an unnatural group but he was happy to disprove that eventually.

For a while, this was actually the mainstream view - the Dinosauria was thought to unite two archosaur groups, the Saurischia and Ornithischia, that weren't actually that closely related. This view was shown to be false, so we actually ended up going back to a Victorian idea about dinosaurs!

[Metallisuchus]

At one point, he believed dinosaurs were an unnatural group but he was happy to disprove that eventually.

For a while, this was actually the mainstream view - the Dinosauria was thought to unite two archosaur groups, the Saurischia and Ornithischia, that weren't actually that closely related. This view was shown to be false, so we actually ended up going back to a Victorian idea about dinosaurs!

I didn't quite know that this was a mainstream view, but I remember wondering this myself when I was a kid (to a much simpler degree, of course).

[Gwangi]

We just can't avoid the notion of pack-hunting can we? Lol. But it's not like it was an original Bakker idea. I think he was just really taking what Ostrom did, and trying to take it as far as he could - trying to really prove that his teacher was right.

Sometimes things can be taken too far.

And yeah, Bakker is the rock star of paleontology, but the guy has done so much to change the old view of dinosaurs.

Changing the view of dinosaurs from the old view is alright but not if the alternative view is equally as extreme as the old. I think Bakker might be guilty of doing that.

Extinction to me is still an open book. I think it was a combination of things, and dinosaurs were becoming scarce towards the end of the Cretaceous anyway.

Some studies suggest they were becoming scarce and some show they were doing fine. I don't know enough about that issue to take a stance one way or the other. I do think however that an asteroid impact or something equally as devastating is the only thing that could have killed off all the non-avian dinosaurs. I don't believe something like disease or climate change could kill off so successful a group without some sort of catalyst. Their extinction could have been due to a combination of things but without that asteroid I feel fairly confident that dinosaurs would still rule the planet and we probably wouldn't be here.

[stoneage]

We just can't avoid the notion of pack-hunting can we? Lol. But it's not like it was an original Bakker idea. I think he was just really taking what Ostrom did, and trying to take it as far as he could - trying to really prove that his teacher was right.

Sometimes things can be taken too far.

And yeah, Bakker is the rock star of paleontology, but the guy has done so much to change the old view of dinosaurs.

Changing the view of dinosaurs from the old view is alright but not if the alternative view is equally as extreme as the old. I think Bakker might be guilty of doing that.

Extinction to me is still an open book. I think it was a combination of things, and dinosaurs were becoming scarce towards the end of the Cretaceous anyway.

Some studies suggest they were becoming scarce and some show they were doing fine. I don't know enough about that issue to take a stance one way or the other. I do think however that an asteroid impact or something equally as devastating is the only thing that could have killed off all the non-avian dinosaurs. I don't believe something like disease or climate change could kill off so successful a group without some sort of catalyst. Their extinction could have been due to a combination of things but without that asteroid I feel fairly confident that dinosaurs would still rule the planet and we probably wouldn't be here.

Bakker said all of the dinosaurs died from Diarrhea, before the asteroid hit.

[stoneage]

 SORRY

[stoneage]

 Sorry

[Metallisuchus]

We just can't avoid the notion of pack-hunting can we? Lol. But it's not like it was an original Bakker idea. I think he was just really taking what Ostrom did, and trying to take it as far as he could - trying to really prove that his teacher was right.

Sometimes things can be taken too far.

And yeah, Bakker is the rock star of paleontology, but the guy has done so much to change the old view of dinosaurs.

Changing the view of dinosaurs from the old view is alright but not if the alternative view is equally as extreme as the old. I think Bakker might be guilty of doing that.

Well that "2nd view"... I think the biggest mistake there - is overestimating their intelligence which was done more-so in pop culture than in actual science. Other than that, what I notice has changed since then is that some dinosaurs are seen as even MORE bird-like than they were back then. In other words, the "3rd view" is more extreme in some ways, and less extreme in other ways.

Extinction to me is still an open book. I think it was a combination of things, and dinosaurs were becoming scarce towards the end of the Cretaceous anyway.

Some studies suggest they were becoming scarce and some show they were doing fine. I don't know enough about that issue to take a stance one way or the other. I do think however that an asteroid impact or something equally as devastating is the only thing that could have killed off all the non-avian dinosaurs. I don't believe something like disease or climate change could kill off so successful a group without some sort of catalyst. Their extinction could have been due to a combination of things but without that asteroid I feel fairly confident that dinosaurs would still rule the planet and we probably wouldn't be here.

Bakker's method regarding dinosaur scarcity isn't THAT reliable anyway, so I'm very open to the fact that it might be misleading. He explains it in his book, and I can see how he came to that conclusion, but he's a little TOO confident in that method, in my opinion. I agree with what you're saying here. I don't feel the asteroid was the only reason they went extinct. I think there would have been a bottle-necking in their population and eventually, a re-population if that meteor never struck. Catalyst is a great word here - it was a contributing cause, not the ONLY cause. To me, what makes it such a mystery is that...

A) Birds survived
B) Crocodiles survived (off-topic: these two facts contribute to why I think you can't simply assume dinosaurs behaved and lived the same way these 2 types of animals did)
C) Marine reptiles died out
D) Pterosaurs died out
E) Mammals survived



Why did certain groups survive and others went extinct?

[Gwangi]

Bakker's method regarding dinosaur scarcity isn't THAT reliable anyway, so I'm very open to the fact that it might be misleading. He explains it in his book, and I can see how he came to that conclusion, but he's a little TOO confident in that method, in my opinion. I agree with what you're saying here. I don't feel the asteroid was the only reason they went extinct. I think there would have been a bottle-necking in their population and eventually, a re-population if that meteor never struck. Catalyst is a great word here - it was a contributing cause, not the ONLY cause. To me, what makes it such a mystery is that...

A) Birds survived
B) Crocodiles survived (off-topic: these two facts contribute to why I think you can't simply assume dinosaurs behaved and lived the same way these 2 types of animals did)
C) Marine reptiles died out
D) Pterosaurs died out
E) Mammals survived



Why did certain groups survive and others went extinct?

Well if you look at the numbers you'll see that even those animals that did survive did so barely. Something like 95% of birds and 90% of mammals also went extinct (someone correct me if my percentages are wrong). Heck, some entire groups of birds like Enantiornithes died out completely and they were the most abundant and diverse group of birds during the Mesozoic. I think if you look at the animals that died out and compare them to those that didn't you'll notice a trend. It would seem small terrestrial animals made it through (birds and mammals) while anything much larger than those died out. Most dinosaurs were large, even most small dinosaurs were as big as the largest mammals of the time. Birds could also fly so that likely helped. Pterosaurus do seem to have been on their way out already, maybe due to competition with birds. Crocodiles and other freshwater dwelling reptiles (turtles) made it. So while large terrestrial animals and marine animals died out, freshwater and small terrestrial animals made it through. That certainly doesn't sound like a disease was at work because what disease would kill all the dinosaurs (aside from birds for some reason) and also kill off unrelated marine reptiles and ammonites? The asteroid theory is a good one and in my mind damn near conclusive. As conclusive as the dinosaur-bird connection for me. Then there is also the volcanic eruptions going on in India at the time as well which may have played a part. But dinosaurs were going extinct and evolving for 160 million years, I see no reason that they would have suddenly went extinct without something as powerful as an asteroid impact.

EDIT: I still think it is safe to look at birds and crocodiles in understanding dinosaur behavior. I don't think behavior really played a role in dinosaur extinction. I think size and habitat were the clinchers. Dinosaurs may have behaved just like large birds or crocodiles but weren't spared simply due to their size, inability to fly or thrive in the same habitats.

[stoneage]

There are no dead dinosaurs in the Iridium sediments laid down by the asteroid impact.  They were already gone.

http://blog.hmns.org/?p=5373

[CityRaptor]

Assuming that the fossil record is complete. I don't think so.
We should also  take local trends into account. While there seems to be some decrease in NA Dinosaurs, those in Asia became more diverse at the same time.