Dinosaur Posture Still Wrong, Says Study

An anonymous reader sends along a piece in Cosmos about new dissension to the current prevailing wisdom on dinosaur posture. The researchers admit that blood pressure presents an unresolved obstacle to their model of dinosaur heads held high. "The current depiction of the way giant sauropod dinosaurs held their necks is probably wrong, says a new study. 'For the last decade the reigning paradigm in palaeontology has been that the big sauropod dinosaurs held their necks out straight and their heads down low,' said co-author Matt Wedel, who researches biomechanics at the Western University of Health Sciences in Pomona, California. But 'our research [now] suggests that this view of sauropods is simply incorrect, based on everything we know about living animals,' he said." The researchers worried that some other team might beat them to publication, so obvious did they consider their methodology of looking at living animals to gain insight into the biomechanics of extinct ones.

Comments

AW...

[The Living Fractal]

Guess this means there was no Stuckupasaurus? You know, the snooty dinosaur who thought it was better than all the others and walked around holding its head high and looking down its nose at the others? ...ok, wow, THAT was lame.

I apologize.

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[TinBromide]

So they looked at a giraffe and decided that the giraffe may be a suitable long-necked living animal? Unfortunately TFS only says that the horizontal configuration is incorrect, and I can't get to the article to see how they posit that long-necked animals posture themselves. So, I'm suggesting that the long neck is held vertically as a way of gaining extra height for food reach, reaching the ground, and longer range vision without the increased bulk of longer legs, taller body, etc.

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[MozeeToby]

The with the vertical posture is blood pressure and the energy required to move blood to the head. Supposedly, just moving blood up the neck to the head would require have the dinosaurs energy and a heart 15 times bigger (as a ratio of body mass) than the hearts of other large animals.

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[Red Flayer]

So, I'm suggesting that the long neck is held vertically as a way of gaining extra height for food reach, reaching the ground, and longer range vision without the increased bulk of longer legs, taller body, etc.

Not only that, but I'd conjecture that the long neck must have evolved vertically. The musculature required to hold a long neck like that horizontal must be enormous, and hardly an efficient way of bearing weight. Plus, is it any coincidence that the large dinosaur neckbones look kind of like hip bones, the primary vertical weight-bearing bone in people?

And the BS about the massive tail counterbalancing a long neck... for that to work as an opposing force on the neck, with the body as a fulcrum... well... that would required the spine to be pretty rigid. I'm not sure how well that would work in practice.

On a side note, have you ever seen a giraffe try to reach the ground with their head? It's pretty amusing. It reminds me of myself, trying to pick up my kids crayons from the floor... it's a whole lot of effort (what? so I'm not in shape or flexible. That's normal here, right?)

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[TinBromide]

Since I couldn't get to the article (still can't), I was extrapolating the posture of living long necked animals. Off hand, I can't think of any long necked animals that don't keep it in a vertical configuration, it seems like it'd be a waste to have a long neck without the defensive/food advantages that go along with it. It'd be like bats evolving wings, but not having the pectoral muscles to flap them enough to fly.

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[Anonymous Coward]

Round is a shape, and we all love our women to be flexible.

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[whiledo]

Yes, it is rather awkward. Not the best video I've seen, but the best I could find on youtube. I've seen some where it's a much longer drawn out process.

When you see giraffes doing the neck-slapping thing, you can see how when their necks bend sideways, it's not a continuous curve but rather like a low-grade 3d render of one with vertices at each vertebra.

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[erroneus]

Oh for God's sake! I thought this was put to rest a long time ago. The most famously known sauropod, the brontosaurus (I know they changed the name! I like the old one! Apata-whatever? Please! Thanks to the name Brontosaurus, every time I hear the word bronchitis I think of dinosaurs) has been established to have lived mostly submerged in the water. I'd say that even passing knowledge of how doing exercises in a pool helps the elderly recuperate should go a long way to aid in understanding how a mostly submarine dinosaur's heart working to pump blood all over its body. Whales get big like they do and otherwise couldn't if it weren't for being in the water. Hippos do like that too.

The giraffe is certainly an animal that pushes certain limits, but its overall weight and height is nothing compared to what a brontosaur would have to maintain.

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[Captain Hook]

But having a 15 ft long neck which is held horizontal means you can browse a 30ft wide path without moving (or perhaps while moving slowly in one direction), the energy saving for being able to browse a large swath of ground without moving must be large when you weight a few tonnes.

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[Useful Wheat]

You need a larger imagination. You have successfully described flying squirrels. I think they fit the category nicely for bats with wings that cannot fly. Go over to wikipedia and look at them for yourself. http://en.wikipedia.org/wiki/Flying_squirrel

They also have flying possums, but they lack the name recognition (thanks Rocky and Bullwinkle!).

As an engineer, I have to design pumps to move fluid through pipes, and one of the biggest factors you have is the height at the destination of the fluid. Running this calculation right now, a mere 1 foot of height increase is roughly the same as pumping something an extra 20 feet. Now that might not seem like much, but add 10 feet of height to a line (such as a vein in a neck) and you are looking at 200 feet of pipe.

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[X0563511]

Sort of like an ostrich's wings?

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[lgw]

Giraffes don't have any extra vertebrae, so their necks are mostly rigid.

Drinking water must be a challenge for a giraffe, as he can't "swallow up"!

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[Anonymous Coward]

yeah but the blood system is a (usually) closed system so the blood pumping up is offset somewhat by the blood coming down. it's a CIRCULATORY system !

Blasted engineers, think ye know it all because you went to school for a while.

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[TinBromide]

But a flying squirrel has glide flaps, not wings. I have a pretty good imagionation, but have a hard time imagining a flying squirrel flapping its glide flaps hard enough to fly, there's a reason why plane wings are much longer side to side than they are horizontally: Drag. A flying squirrel has a surface that would turn it into a square which is sub optimal for flight, if you look at a bat's wing span, it trades robust arms (which flying squirrels have) for a gossamer wing membrane stretched over tiny bones. It seems like that a flying squirrel has a nice trade-off mix for ground/air combo, but a bat would be at a severe disadvantage on the ground if it couldn't take off. (yes, i know little birds would be worse off, but ground based birds run faster, swim (penguins) or have other methods of evading predators).

A bat without the pecs to effectively make use of its frail arms and fragile wing-skin would probably be the evolutionary equivalent of fast food.

So, you, like TFS (which is sort of what i was criticizing with my original post), only debunk, what's your theory as to why long necked dinosaurs had long necks?

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[TinBromide]

traded for fast running speed and overall size.

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[Anonymous Coward]

I thought it was the bracciosaurus that lived in the water?

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[Anonymous Coward]

But having a 15 ft long neck which is held horizontal means you can browse a 30ft wide path without moving (or perhaps while moving slowly in one direction), the energy saving for being able to browse a large swath of ground without moving must be large when you weight a few tonnes.

Ever held your arm out straight and put a large book on your palm & tried to keep from moving? The idea that solving for the blood pressure problem by having horizontal necks makes more sense than solving for the muscle fatigue problem by aligning the neck vertically is ludicrous.

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[Binestar]

http://www.unmuseum.org/dinobront.htm

Today, scientist's vision of the habits and habitat of the Apatosaurus are quite different than what Marsh and other early paleontologists had thought. Early analysis suggested that the animals must have been weak because their small heads could only chew the minimum amount of food necessary to fuel such a big body. So weak, in fact, that large sauropods were thought to be slow, unable to lift their bulky tails off the ground and only able to support their massive weight by living in shallow lakes and swamps where water floated their bulk.

Paleontologists like Bakker showed that this image was wrong. No Apatosaurus skeleton has been found in an ancient body of water and its feet were not at all suited for walking through marshy and muddy ground. In fact, Bakker notes in his book Dinosaur Heresies, an analysis of changes in geology over time suggest that large sauropods moved out of areas as they became wet: they didn't like swamps at all.

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[Golddess]

Try standing perfectly still for hours on end, not flexing your legs even one bit. Sure, circulation will still happen (it's not like the circulatory system is one single loop, it's more like a beltway with various on/off ramps to do your thing in the city, then get back on the beltway in a totally different location), but blood will pool in your legs and it can cause issues by stretching out your veins and you'll start to feel light-headed and might even pass out.

As a results, veins are basically one-way valves. By flexing your muscles, you constrict your veins, forcing the blood within to go in the only direction they allow (back towards the heart).

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[erroneus]

With the possible exception of the smaller sauropods, some of the random information I have gleaned in the past had revealed that the larger ones were swamp dwellers with a big chunk of skin draping their necks as revealed in some article that was, ironically enough, was mentioned here on slashdot. Must have been more than two years ago I think. The notion that they were actually hanging out in the water most of the time served to answer a lot of things like how they could actually get that big to begin with.

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[Anonymous Coward]

Except, this is not true. There is absolutely no evidence in evolutionary biology to justify the myth that long necks in giraffes exist to help them get higher food as a evolutionary advantage. In fact there is a lot of evidence to the contrary. It's surprisingly interesting stuff if you google it.

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[Anonymous Coward]

Not really, giraffe's have valves in their neck arteries -- hence you don't need insane amount of blood pressure from the heart (the valves keep the blood from falling down after being pushed up).

My guess is that these long-necked dinosaurs probably had valves in their arteries just as giraffes do today...

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[jimbolauski]

High blood pressure is not the only delivery system possible a sauropod's neck muscles could be used to help move blood.

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[wildsurf]

When thinking about dinosaurs' long necks, it's helpful to consider the possibility that the atmosphere was much thicker back then. So fluids could be drawn much higher without introducing vacuum problems, and it also explains how such huge insects and proto-birds (e.g. pterodactyls) could have flown there. Interesting stuff.

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[Anonymous Coward]

Where's your source for the "submerged dinosaur" hypothesis being established? Are you sure it's accepted by the vast majority of paleontologists?

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[Just_Say_Duhhh]

Of course, it could be that the dinosaur's head position is a result of his current mood. In the morning, he's feeling good, head held high. After a full day of coding, debugging, and endless meetings with management, his head will be dragging on the ground. His blood pressure will be elevated, but not BECAUSE his head is dragging - they are both symptoms of overwork.

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[Sique]

Pterodactyls are no proto-birds, they aren't even directly related to birds. Flying has evolved several times in reptiles, and pterodactyls were just one strand of flying reptils.

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[Locke2005]

have you ever seen a giraffe try to reach the ground with their head? Almost as amusing as watching a deer run up a flight of stairs. However, since giraffes do that on a regular basis to drink water, you'd think they would be better at it.

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[maxume]

By here, do you mean America, or Earth?

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[Richy_T]

Do they take account of the fact that the blood comes back down again? You might need a heart that size if you are pumping the blood at atmospheric pressure but if you keep the pressure built up on the veinous side, you just need to provide a pressure differential and to overcome viscous resistance.

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[maxume]

I'm pretty sure gravity is the problem, not vacuum (just carry some decent amount of water up a flight of stairs if you doubt this).

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[Red Flayer]

I meant on Slashdot.

But America works just as well.

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[Useful Wheat]

I like Captain Hook's theory (the post above mine) with a slight modification. In addition to being useful for grazing a large area while remaining mostly still (cover a 30 foot circle while stationary) long necks are also used in the mating ritual. Physical attractiveness (in the eyes of the animal) is a powerful force. Particularly in birds, in which the male tends to be colorful (such as a male peacock) while the female tends to blend in with the environment.

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[CherniyVolk]

Several species of turtles have debatably "long" necks, and they are all maintained in a horizontal position. http://en.wikipedia.org/wiki/Roti_Island_Snake-necked_Turtle

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[Anonymous Coward]

When thinking about dinosaurs' long necks, it's helpful to consider the possibility that the atmosphere was much thicker

Apparently, the atmosphere contained at least 30% oxygen (source: some Discovery documentary). Since the dinosaurs developed in this environment they must have been able to use the additional oxygen to their advantage. A slower blood flow could have transferred a reasonable amount of oxygen in this case.

proto-birds (e.g. pterodactyls) could have flown there.

Pterosaurs did have hollow bones in the same way modern birds have and the maximum wingspan of 10 meters is not so large considering the largest know bird, Argentavis magnificens, could have had a wingspan of 7 meters. Pterosaurs probably also had a larger effective wing area than modern birds considering the structures of bats and the (human) ideas of using the body of an airplane as a lifting surface in the form of flying wing, for example. These lifting structures would not necessary have survived in the fossilization process.

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[init100]

Not really, giraffe's have valves in their neck arteries -- hence you don't need insane amount of blood pressure from the heart (the valves keep the blood from falling down after being pushed up).

Actually, most (all?) animals with a circulatory system have backflow prevention flaps in their veins. Having them in arteries is just a simple extension to this concept.

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[nyctopterus]

No, they didn't just look at giraffes--they looked at a wide variety of tetrapods, all of which hold their necks close to as they will go. It's seems that it's standard among land vertebrates, and isn't reflected in their vertebra.

The paper is here. ... and a blog maintained by the authors giving you context and further information is the ever-exciting Sauropod Vertebra Picture of the Week or SV-POW!

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[nyctopterus]

Most people who study the aerodynamics of pterosaurs don't think they would have had a problem flying in today's atmosphere. the thicker atmosphere stuff is definitely fringe science.

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[nyctopterus]

That is in a forthcoming paper according to their blog SV-POW! (Sauropod Vertebra Picture Of the Week.)

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[Mr. Slippery]

it's helpful to consider the possibility that the atmosphere was much thicker back then

Thicker? Quite possibly. But 370 atmospheres? That link is the best crank science since the Time Cube, man.

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[nyctopterus]

I can't did up the reference right now, but it turns out the eneregy requirements for maintaining the long neck outweigh the cost of simply walking to the food.

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[nyctopterus]

Note that they are aquatic. The extended neck posture found in virtually all terrestrial tetrapods probably has to do with getting a view above the ground, and being the most efficient posture. Neither of these things applies nearly so much under water,

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[Anonymous Coward]

Wasn't it a brontoburger that tipped over Fred Flinstones car at the drive-in restaraunt?

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[PitaBred]

So why are birds able to hold their wings out for hours or days on end? It is in no way comparable to your arm, because you arm and ligaments aren't built that way. It's entirely possible that the tissues of the sauropods supported their necks relatively effortlessly (what about a cow's massive head, held out horizontally?)

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[againjj]

The original paper (at http://www.app.pan.pl/article/item/app54-213.html) basically says that the "osteological neutral pose" (ONP) (basically the pose where the bones make maximal contact with each other) is not necessarily the pose most commonly held. Apparently, the first and only good study of neck and tail position concluded that the then currently accepted pose was unlikely and that ONP was probable, and then every one else simply accepted that without further study.

The authors went looking at current animal poses and concluded two things. First, in modern animals, ONP is not always the pose held by default, and in fact assuming ONP as default in sauropods has some difficult-to-explain ramifications (though a vertical default does as well). Second, even if ONP is the default pose, there is generally much movement away from that pose for various activities in modern, like drinking and running, and so it is likely that sauropods had that too.

The authors also, of course, hedge their bets and say that their ideas may be totally off if there is something they aren't aware of, like specialized tendon structure for the neck or other such things.

In short: the authors say that the conclusion that sauropods have horizontal necks was based on assumptions that are unsound.

Oh, and TFA:

BRISBANE: The current depiction of the way giant sauropod dinosaurs held their necks is probably wrong, says a new study.

"For the last decade the reigning paradigm in palaeontology has been that the big sauropod dinosaurs held their necks out straight and their heads down low," said co-author Matt Wedel, who researches biomechanics at the Western University of Health Sciences in Pomona, California.

But "our research [now] suggests that this view of sauropods is simply incorrect, based on everything we know about living animals," he said.

Unrealistic posture

According to the report in the report in the journal Acta Palaeontologica Polonica, sauropods held their necks up in the same way as many living vertebrates, in a swan-like 's' curve, rather than in the horizontal pose commonly shown in everything from museum reconstructions to plastic toys.

For many decades, scientists supposed that sauropods had long necks so they could browse high in the treetops and depicted them, like giraffes, with their heads held high. But a 1999 Science paper led to a shift in the way sauropods were shown.

The authors of that paper argued that the habitual pose of an animal's neck could be easily found by lining up the vertebrae in maximum contact, which gave a horizontal pose for most sauropods. Estimates of blood pressure also suggested that it would have been very difficult for sauropods to pump their blood up to such a height.

Blood pressure problem

"The problem is, living animals don't hold their necks in that posture," Wedel said. After stumbling across a paper from the 1980s that showed that most land animals held their necks vertically, Wedel's team looked for clues to sauropod posture in X-rays of living animals.

They found that reptiles and amphibians held their necks mostly horizontally, while mammals and birds (which are more closely related to dinosaurs and share their upright leg structures) all held their necks vertically.

Studying the neck movements of living creatures also suggested that sauropods had a greater range of movement than previously thought.

While scientists had assumed that the dinosaur neck vertebrae overlapped each other by around 50%, that's not true for living creatures like ostriches and giraffes, which can extend their necks till the vertebrae hardly overlap at all.

Their method was so simple that the team was worried someone else would publish the findings before they could. "We did get a bit paranoid... it just seemed so obvious that if you want to know what extinct animals did, you shoul

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[TinBromide]

wings provide lift and they're balancing the up force on the wings against the down force of the body with massive pecs.

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[Anonymous Coward]

"Not only that, but I'd conjecture that the long neck must have evolved vertically. The musculature required to hold a long neck like that horizontal must be enormous, and hardly an efficient way of bearing weight."

Sauropod dinosaurs had a large nuchal ligament running from their shoulders along the top of the neck. IT doesn't usually preserve, but rare specimens have it, and the notch that it sits in is visible on the dorsal side of the vertebrae. It would have supported much of the weight, somewhat like the cable of a suspension bridge (but a one-sided structure). The bones are also remarkably light weight, with substantial internal gas-filled cavities (pneumatic bones) -- rather like the bones of birds. The structure would have been *much* lighter overall than a mammalian equivalent.

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[TinBromide]

As an explanation of my above post, the wings are supporting the body due to the lifting force applied to the wings balancing out the gravity of the torso. The joints lock into place and prevent the wings from forming too much of a V shape. If you've ever broken apart a whole chicken, you'd feel the resistance put in place when you try to put the wings at more than 90 degrees perpendicular from the body. Its the same reason why you can't reach stick your arms straight out from the body at 90 degrees perpendicular to the body (similar to the pose in leonardo da vinci's man-in-circle sketch), and bring them much further back without twisting, the bones prevent it. (I know you can touch your hands behind your back, but that's not the positions birds fly in)

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[shadowofwind]

Most people who study the aerodynamics of pterosaurs don't think they would have had a problem flying in today's atmosphere. the thicker atmosphere stuff is definitely fringe science.

Fringe my foot! The reduced UV rays is the only way to explain how some people in the Old Testament lived past 200.

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[Minwee]

I'm pretty sure gravity is the problem

Well that's simple, just change the gravitational constant of the universe.

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[shess]

I can't did up the reference right now, but it turns out the eneregy requirements for maintaining the long neck outweigh the cost of simply walking to the food.

Meaning dinosaurs did not have long necks. QED.

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[rtb61]

Of course if you had any dinosaurs left you could check to see whether major arteries were enclosed in musculature which assisted pumping the blood. Of course this evolutionary trait would be restricted only to major sauropods due to the inherent energy waste where it is not required and then perhaps only in the neck.

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[Brian Gordon]

The lift on the wings and weight of the body just makes it more remarkable that they're able to fly for long periods of time because those forces conspire to make that V shape and the bird has to fight it. And that resistance isn't from effortless (and painful) locking of bones, it's from strong muscles and ligaments.

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[Anonymous Coward]

Read his link, it's very interesting, and well sourced. Basically the gist of it comes down to the atmosphere being thicker to the order of having a density about 2/3 that of water. therefore you have birds that get net gain bouyancy, Velociraptors using tails as propulsion, etc. very interesting theory and it should be interesting to see how it survives review.

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[Brian Gordon]

Eh, I think his point is that any work done to offset gravity is done by gravity to get back down. What comes up must come down. You're right though because there's a lot of energy lost to friction and your muscles have to contribute a lot.

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[Sulphur]

If a few veins or arteries had peristalsis (distributed pumping), then the pressure difference could be less perhaps?

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[fractoid]

Ever held your arm out straight and put a large book on your palm & tried to keep from moving?

Reptile muscles work differently to mammalian muscles, I believe. That's why reptiles can hold awkward poses for hours at a time, while mammals tend to keep moving. Also, there's a difference between slow and fast muscles - you don't have any trouble holding your head balanced on top of your neck for 12 hours at a time, which actually takes quite a lot of strength. Contrariwise, your arm will contain mostly fast muscle fibres (unless you're a yoga or tai chi master) because it requires more strength on a much lower duty cycle.

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[Randle_Revar]

I was wondering if some would post the paper. Do you read Tet Zoo also?

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[PitaBred]

And if the neck is braced against the strong legs of the dinosaur (think a suspension bridge), how is that any different? Seriously... it's not that hard to imagine looking at a dinosaur skeleton

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[tompaulco]

it's helpful to consider the possibility that the atmosphere was much thicker
Not to mention that the Earth was around 6X10^13 less massive, perhaps even more, depending on how much meteorite dust rained down back then. It seems likely that there was more meteorite dust falling back then.
Of course, being closer in relation to the amphibians, perhaps they were able to absorb oxygen through their skin. Or perhaps, as I read in at least one dinosaur book back in the 70's, they had multiple hearts.

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[Anonymous Coward]

Bakker published in the 1970's. I think that they did not do a literature search before publishing. No PHD for you!

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[SleepingWaterBear]

Come on. Someone mod this up. If slashdot doesn't reward obscure references to single lines of Star Trek dialog, who will?

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[Anonymous Coward]

Ever held your arm out straight and put a large book on your palm & tried to keep from moving? The idea that solving for the blood pressure problem by having horizontal necks makes more sense than solving for the muscle fatigue problem by aligning the neck vertically is ludicrous.

I certainly have held my arm out straight with nothing on it and experienced less fatigue, since that is what my arm is intended to be able to do. Do you think any creature would last very long in the world if their neck couldn't support their head? Animals aren't weak - they spend all their time moving. Just because we get fat and squishy eating Cheetos and reading Slashdot doesn't mean you should believe animals are the same way.

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[TheLink]

But you do need enough pressure to actually move the blood _up_. Unless you're saying the dinosaurs lowered their heads to allow blood movement, then only stick their heads up when necessary.

A theory of mine is that long necked dinosaurs had auxiliary hearts in their necks - so the chest heart only needs to pump part of the way up, the neck heart(s) takes care of the other part. To me that would make more sense than a single massive chest heart with enough pressure to pump all the way. But since soft tissue isn't well preserved/fossilized, it's going to be hard to get evidence. As it is there are very few fossilized dinosaur hearts found, and I doubt anybody is looking for heart like stuff in the neck area.

Some dinosaurs already had auxiliary brains - nerve impulses take rather long to travel all the way from the tail to the head. So why not extra hearts?

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[Anonymous Coward]

I think they hold them in a moebious string to minimize height when not eating. problem solved.

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[rxan]

Thing is that not all sauropods held their necks in this way. Diplodocus held their necks pretty much horizontally, using their long tails as a counterbalance. Brachiosaurus/Brontosaurus held their necks more vertically, and did not have as long of a tail as the diplodocus. As the spines of humans has shown, we don't exactly line up the way we were meant to. Perhaps this is the same for the dinosaurs.

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[Cowmonaut]

How's this for a defense advantage: long tails. Caveat: I first heard the idea from Jurassic Park (the second book), but it isn't an unreasonable theory. I wish we could be more accurate with our muscle models. All we have is the frames to go by. Do the same thing with an automobile and you'll probably never guess what the car really looks like.

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[JasonKChapman]

The odd thing is that everyone assumes the long blood vessels to be fixed-diameter pipes. If the musculature included a kind of esophageal motion that helped to squeeze the blood upward, the heart wouldn't need to do as much work.

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[tabrnaker]

Nah, the heart isn't the only muscle that contributes to blood pumping. Those huge leg muscles help pump with every single movement.

Then, in some bizarre never before seen biological feat, the scientists will discover that the blood also gets moving by thermal differences between the head and the body. Going for $20, any takers?

Scientists will also forget their stupidity and realize that dinosaurs don't constantly hold the same posture. After all, how much blood do you need in your head when your brain is in your ass? Amazingly, they'll discover that if a dinosaur starts to get pins and needles in their head, they just have to lower their head to chew on some low lying foliage and their blood supply to their peanut brains gets restocked.

Remember folks, you saw it here first!

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[tabrnaker]

yoga and tai chi don't use muscle contraction for movement, they use muscle expansion, hence the reason why you can 'hold' positions for long periods of time.

Please don't try to argue unless you can be in handstand and carry on a conversation effortlessly for over a minute. Because if you can't, you have no internal knowledge of mechanics and posture.

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[4D6963]

Do you even know how barometers work? They work by putting mercury in a tube, inverting that tube into a bath of mercury so that mercury flows freely in and out of the tube and interfaces with the atmosphere. As you go up in the tube the pressure for the mercury gradually decreases, to the point that 76 millimetres above the surface the pressure drops to 0, so the mercury can't go any higher. You can do the same with a column of water over 10 meters high too. Anyways the point is, if the atmospheric density is 370 times higher as speculated in GP's link, then instead of stopping at 76 millimetres the mercury would now be able to go as high as 28 metres (not that I'm saying it would have been this dense). Please tell me you see how that relates to blood going up vertically in veins in the neck of gigantic animals.

By the way the really sad part is that you were modded anything else than Funny. I guess people in IT don't have such a good recollection of high school physics.

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[4D6963]

Well I must say it does indeed sound like quite a hell of a value, but other than that fact, can you elaborate on why it makes it crank science?

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[maxume]

Forgive me for responding based on reality, rather than nonsense.

Anyway, even in the nonsense-verse, the pressure required to pump blood up 15 feet is quite likely to exceed the difference in atmospheric pressure over those 15 feet (the important part here is that only the delta can help push the blood up, the air at the top is pushing down...); animals don't maintain a vacuum in their brains and diffuse oxygen up a column of liquid, so a barometer is pretty much a useless analogy.

In our present day atmosphere, 15 feet of altitude provides a pressure difference of less than 1 mmHG (and that is starting at sea level, start higher and you will get less of a drop), about 1% of the pressure required to circulate blood through our puny human bodies. I used this widget to make that calculation:

http://hyperphysics.phy-astr.gsu.edu/hbase/Kinetic/barfor.html

That's using 760 mmHg as ground pressure, 30 degC as a temperature (using a lower temperature doesn't change it much), and 15 feet as an altitude.

I'm pretty sure the formula is an approximation, so just plugging in huge numbers won't be real accurate, but plugging in a pressure of 282,000 mmHg (that's 370 atmospheres) does give 150mmHg of difference, enough to have a real impact, even for a huge creature. A 15 foot neck means that the blood pressure needs to be able to push, roughly, a 15 foot column of water, which is equivalent to about 350 mmHg. So an ultra-thick (probably to the point of absurdity) atmosphere could certainly help, but that is all it is going to do, the creatures are still going to face an interesting problem.

Re:TFA Is slashdotted

[4D6963]

I think the problem is not the aerodynamics but the power it would take for the animal to fly (at least according to this page)

Re:TFA Is slashdotted

[nyctopterus]

His estimates for the mass of Quetzalcoatlus is ridiculousness high, close to ten times it's mass estimated by a variety of other methods (including volume models, among others). You can pretty much chuck out his results based on that.

Re:TFA Is slashdotted

[4D6963]

True, I noticed that after some more reading.

Re:TFA Is slashdotted

[jc42]

A number of researchers have reported evidence that both the oxygen and CO2 levels were higher than now in the Cretaceous atmosphere. Nothing like a factor of 370, of course, more like 20% or 40% higher. And, of course, other researchers point out that this should be considered just an "interesting hypothesis" until more supporting evidence is found. The idea is generally accepted as probably true, but the numbers' precision isn't great, so further research is needed.

Two orders of magnitude is definitely stretching the idea into "crank science" territory.

Re:TFA Is slashdotted

[4D6963]

It sounds like you're confusing proportions with atmospheric density. But yeah, two orders of magnitude is a bit much, and no peer-reviewed paper anywhere to give it some credence. It is nonetheless an interesting idea indeed.

Re:TFA Is slashdotted

[jc42]

A theory of mine is that long necked dinosaurs had auxiliary hearts in their necks ...

Possible, but we might not recognize them even in fossilized soft tissues. Such a "heart" could easily evolve from an artery that passes between (or through) muscles. Then the normal flexing of the neck, combined with one-way valves in the arteries, would function to life the blood upward. Once such a configuration exists, the usual selection process could slowly make it more effective. But the result could still look just like an artery passing through musculature, with little obvious evidence that the muscles are modified to assist in the pumping in addition to their original function.

It's too bad that a few of the big ones didn't get another 65 million years to evolve. We could have some good data on the topic by now.

Re:TFA Is slashdotted

[jc42]

Well, we do have plenty of long-necked dinosaurs in our world today. But the biggest (ostriches, geese, etc.) aren't nearly big enough to tell us much about the truly huge ones that were around 70 or 90 million years ago. Even an ostrich's neck doesn't need much assistance in lifting blood to the head. They're also in a different suborder, unfortunately.

Re:TFA Is slashdotted

[Anonymous Coward]

You clearly have no clue how pumps work. Pumps move fluid, creating a pressure differential. If the inflow isn't in some way sealed from the outflow (via valves, gaskets, etc.) the fluid will won't go anywhere. So the pressure of the blood that "comes back down" is immaterial.

Also, even if you raise the average pressure in the system, the pressure difference between top and bottom is the same!

Re:TFA Is slashdotted

[againjj]

No. I found the link though another post.

Has anyone considered that maybe the dinosaurs

[antifoidulus]

were just really emo?

Re:Has anyone considered that maybe the dinosaurs

[Red Flayer]

Huh? Why would a dinosaur be emo?

It's not like my lawn in sleepytime, where I get to be a Viking but my lawn is emo because it cuts itself.

I'm sure there's something to your joke, but I just don't get it... can you explain?

Re:Has anyone considered that maybe the dinosaurs

[Jake Griffin]

the big sauropod dinosaurs held...their heads down low

Wait for it... wait for it... there ya go! You get it now!

Re:Has anyone considered that maybe the dinosaurs

[skine]

So the dinosaurs listened to the Rites of Spring and Embrace, were greatly influenced by Husker Du and the DC hardcore scene?

Or were they second wave Emo, listening to Braid, Cap'n Jazz, Sunny Day Real Estate and Texas is the Reason while treating Fugazi and the Pixies like gods?

It's too bad there was no third wave of emo. There were some pretty good bands starting out in the early aughts, too.

Re:Has anyone considered that maybe the dinosaurs

[Anonymous Coward]

Don't give up the day job.

Re:Has anyone considered that maybe the dinosaurs

[Red Flayer]

Thanks. I didn't know emo kids held their heads low. I don't understand a lot of the newfangled slang in my dotage.

Re:Has anyone considered that maybe the dinosaurs

[Anonymous Coward]

I think the joke is that if the dinosaur were emo it would slouch, ie. have bad posture.

Two Things

[eldavojohn]

Why are we arguing over which position was the default when it's entirely possible that they utilized both positions. Down low for traveling to avoid blood pressure problems and up high for brief states of alert or reaching high food sources? With the flexibility of the vertebrae, I would assume the animal would use it however it most suited them for the time being.

The other thing is how much do we know about the tissues and proteins that made up muscles and blood in Sauropods? Is it possible that they were much stronger or their blood had different properties making it capable of overcoming the blood pressure problem?

I've seen exhibits that portray them both ways. You just might have to accept that you're never going to know for sure ...

... until you CLONE THEM!

*starts humming the Jurrasic Park theme song with a creepy grin on his face*

Re:Two Things

[The Living Fractal]

I suspect that the real case here is that some of today's scientists are holding their heads rather higher than they need to be in this 'race' to publication.

Re:Two Things

[MaXintosh]

Clone them, or get some better impressions of soft tissue. I expect we'll eventually get some, given our history of finding such neat things, but I'm not holding my breath because it's like finding a needle in a haystack.
Er, well, actually more like finding a rock among a planet full of other rocks.

Re:Two Things

[Red Flayer]

Down low for traveling to avoid blood pressure problems and up high for brief states of alert or reaching high food sources?

That was the status quo that the authors of this piece are disputing. Down low is default, up high as needed.

Re: their blood and blood pressure... liquid is liquid. Gravity is gravity. Pressure required to overcome gravity is just that. If you're suggesting that their tissues were so significantly different that they could withstand ridiculously high pressures, then fine... but I doubt it would be a property of the blood so much as a property of their vasculature and heart.

... until you CLONE THEM!

Oh yeah? What if they are equally capable of either, and how they hold their heads is learned behavior? What has your cloning done for us then?!

Re:Two Things

[spyfrog]

Well, then cloning have given us a cool dinosaur that we could use both to fix our lawns and to trim our trees! Multipurpose dino.

Re:Two Things

[Belial6]

Understand that I am posing this as a real theory, but since we don't have a lot of the soft tissue, there is no way of knowing that the they didn't have more than one 'heart'. If their was a secondary, heart, or even many small pumps, there would be no need for extremely high blood pressure, one giant heart.

Re:Two Things

[OctaviusIII]

Oh, if only... last I heard an atmospheric analysis of the dinosaur's era showed a significantly higher oxygen content than our own atmosphere, meaning any clone would probably be unable to breathe properly. And, since our sauropod problem deals with blood, something tells me the atmosphere would wreck the posture experiment. Damn shame, too, although at least we won't get anybody wondering what a t-rex was like and cloning one of it.

Re:Two Things

[Red Flayer]

Well, I've read about this theory before, and while it is certainly possible, I think it's unlikely...

No other vertebrates are observed to have multiple hearts. IIRC, the giraffe does have a mechanism to deal with the BP in the head (I think they can block off blood flow or something), and maybe a valve system would provide what's necessary...

What if the major artery in the neck was capable of waves of constriction to force blood upwards, like milking a cow in reverse?

As you say, lots of possibilities since we don't have the soft tissue.

Re:Two Things

[Chris Mattern]

I spent the last half hour looking for Jurassic Park 4 because of you. Now, I am disappointed because it was most likely canceled with the death of Michael Crichton.

Jurassic Park 4: Dinosaurmageddon!

Re:Two Things

[techess]

I agree until we get a better idea of the soft tissue we won't really know.

Giraffes have a very cool way of improving their circulation without just throwing a bigger heart at the solution:
http://news.softpedia.com/news/Some-Weird-Giraffe-Issues-80555.shtml

"To pump the blood high to the brain, the heart of the giraffe is very large: up to 11 kg (25 pounds). The heart pushes 60 liters of blood per minute. The muscles of the neck arteries are relaxed with each heart beat, helping the propulsion of the blood to the brain. In the neck veins, special valves impede the blood to flow back too rapidly, meanwhile preventing the emergence of a syncope (fainting due to sudden lowering of the blood pressure). At the base of the feet, where pressure is low, there is a system of capillary vessels like in humans, impeding the appearance of edemas. Like humans, the giraffe is one of the few vertebrates which is taller than longer, and NASA studied blood circulation in giraffes for creating an anti-gravity garment for astronauts."

Also horses while not having an extremely long neck also deal with circulation problems by more than throwing in a bigger heart.
http://en.wikipedia.org/wiki/Circulatory_system_of_the_horse
The frog
Each hoof contains a structural component known as the "frog," which covers the deeper structure of the hoof known as the digital cushion, a vessel-filled tissue. When the horse places weight on a leg, the ground pushes upward on the frog, compressing it and the underlying digital cushion. This results in squeezing blood out of the digital cushion, which then helps to pump it back up the leg, helping the heart to work against gravity.

Nature has done some amazing and unique things with soft tissue to get around limitations. It would be so interesting to find out how dinosaurs worked and what their bodies were really like.

Re:Two Things

[lgw]

Giraffe's have a rete mirabile to avoid the head exploding when lowered. This sort of structure has evolved seperately in several unrelated species, so it's quite reasonable that the long-necked dinos had them. The dinos probably didn't need a large blood supply to the brain, the way a mammal does, so the requirements might not be so bad.

Re:Two Things

[bb5ch39t]

gravity is gravity

You are assuming that G is constant over time and space. Some avant-garde scientists are beginning to wonder if this is true.

Re:Two Things

[MindlessAutomata]

Just ask Bozo the Clown, Ph.D.

Re:Two Things

[LWATCDR]

"The other thing is how much do we know about the tissues and proteins that made up muscles and blood in Sauropods? Is it possible that they were much stronger or their blood had different properties making it capable of overcoming the blood pressure problem?"
Umm have we found any animal that has blood or tissues that would solve that issue? Reptile, Bird, or Mammal?
That seems like a huge leap with out some type of evidence of it existing in nature.

Re:Two Things

[Accursed]

I've always kind of wondered if they mostly stuck to rivers and lakes, and used their long necks to reach out and graze trees/shrubs/what have you along the banks.

Re:Two Things

[maxume]

So just use a prototype Mars dome for the zoo.

Re:Two Things

[BJ_Covert_Action]

I would be very wary of cloning any and all dinosaurs if I were you. Unless, of course, you passed your Velociraptor Math Test already....

Re:Two Things

[Anonymous Coward]

The argument is about "habitual" position. Which is, the position defaulted to when not asleep or feeding. That turns out to be, for most tetrapods, elevated to close to the maximum extent. This is interesting, because most literature recently has concentrated on the neutral vertebra articulation as guide to habitual life position. This paper argues, with x-rays to back it up, that this assumption is false. The blog SV-POW! has more information.

Re:Two Things

[Reziac]

I had the same thought -- maybe they just swung their heads down periodically (grazing posture) and that acted as a blood pump. Maybe they had valve structures in the big arteries that prevented blood from flowing back down their necks. Who knows? But holding a neck that heavy out straight in front requires an awful lot of ass end to balance the weight, *plus* extremely strong shoulder structure.

As to modern critters -- Giraffes are as big as some of the midrange dinos, and don't seem to have a huge problem with blood pressure, yet their heads are held aloft...

Re:Two Things

[ddimas]

The questions posed by this article are old news. Bakker settled this back in the early 70's. The maximal contact idea is dependent on the precise configuration of the junction of the nechk and body. In any case, I suspect that it is wrong. The area of maximal contact probably served as a limiting device to keep the things from dragging thier heads in the dirt and stomping themselves to death. The normal pose is more likely to be shown by the configuration of ligament rods and bone scars from the aforesaid ligaments.

Re:Two Things

[Tokerat]

THAT's two-things-ism!!!

Re:Two Things

[Anonymous Coward]

Giraffe's have a rete mirabile to avoid the head exploding when lowered. This sort of structure has evolved seperately in several unrelated species, so it's quite reasonable that the long-necked dinos had them. The dinos probably didn't need a large blood supply to the brain, the way a mammal does, so the requirements might not be so bad.

Does this imply that at some point in their evolutionary history, there was a branch of giraffes whose heads exploded when they lowered them?

Oh, come on

[Daniel Dvorkin]

It was only 6000 years ago -- didn't anyone get any pictures?

Re:Oh, come on

[The Living Fractal]

See the reply to my thread by the AC, and you might have an idea of where the phones were at the time... Ouch.

Re:Oh, come on

[Junior J. Junior III]

Sadly, God Almighty did not inspire man to invent the camera until about 150 years ago, and by that time all the Dinosaurs had been eradicated for being unrepentant sinners, as they so righteously deserved.

Re:Oh, come on

[Anonymous Coward]

Duh!!!

  That was before the world was invented.

  Sigh!

Re:Oh, come on

[smoker2]

God Almighty did not inspire man to invent the camera until about 150 years ago

Wrong.

That's Why They're Extinct?

[Anonymous Coward]

I better get new ergonomic chair for work and for home.

Listen to your mother.

[Anonymous Coward]

Sit up straight! Eat your palm trees! Don't ROAR at your sister! Ignore those tiny furry mousey creatures...they are of no consequenc and won't amount to anything!

Re:Listen to your mother.

[je ne sais quoi]

...I don't care if the neighbors are evolving into birds, we're not doing it. If they were evolving to jump off a cliff, would you do it too? And for the last time, that giant bright spot in the sky the last few days is not an asteroid that will kill us all. I swear, kids these days and their wacky imaginations.

Re:Listen to your mother.

[kurzweilfreak]

NOT DA MAMA!

Re:Listen to your mother.

[Anonymous Coward]

No wonder the mice were furious.

Re:I'm horny

[The Living Fractal]

...brings a whole new meaning to "multi-touch"... and, no.

geese

[Red Flayer]

Well, that was a quick slashdotting. Hopefully they'll be back up soon.

Re: modern pseudo-analogues -- based upon the geese I raised as a kid, I never could quite grok the 'head-held-low' posture. Geese only hold their heads low to screw or to attack. It seems very inefficient for a large creature to hold that much weight horizontally away from the body (remember those physics lessons re: levers and distance from the fulcrum?).

Dinosaurs are awesome, as most five-year-olds will tell you. Armchair paleontology is fun too. And since we slashdotters are so fond of pretending expertise on subjects we know little about, and TFA seems to be slashdotted, I'm looking forward to a very amusing (but maybe not quite so enlightening) discussion.

Re:geese

[Anonymous Coward]

Depends on your definition of "inefficient." It's certainly more efficient than being killed because their head was so low that they didn't see the predator about to eat them.

Re:geese

[Red Flayer]

I think you misread. The inefficient way of bearing the weight is to hold the head low away from the body. The efficient way is high up, so that the skeletal structure can bear a lot of the weight.

Re:geese

[eldavojohn]

Re: modern pseudo-analogues -- based upon the geese I raised as a kid, I never could quite grok the 'head-held-low' posture. Geese only hold their heads low to screw or to attack.

I think it's dangerous to try to compare a two legged winged creature to a four legged creature but from the article:

They found that reptiles and amphibians held their necks mostly horizontally, while mammals and birds (which are more closely related to dinosaurs and share their upright leg structures) all held their necks vertically.

Studying the neck movements of living creatures also suggested that sauropods had a greater range of movement than previously thought.

While scientists had assumed that the dinosaur neck vertebrae overlapped each other by around 50%, that's not true for living creatures like ostriches and giraffes, which can extend their necks till the vertebrae hardly overlap at all.

And in regards to efficiency of the way they hold their neck:

It seems very inefficient for a large creature to hold that much weight horizontally away from the body (remember those physics lessons re: levers and distance from the fulcrum?).

(As the article notes) it's probably a lot harder to have the blood pressure to pump blood all the way up that column to the head. Blood pressure is one of the things they can't explain about their model. The article says, "Estimates of blood pressure also suggested that it would have been very difficult for sauropods to pump their blood up to such a height."

Dinosaurs are awesome, as most five-year-olds will tell you. Armchair paleontology is fun too. And since we slashdotters are so fond of pretending expertise on subjects we know little about, and TFA seems to be slashdotted, I'm looking forward to a very amusing (but maybe not quite so enlightening) discussion.

After reading it, the article's not as great as you think. There's plenty of pictures on Wikipedia of the animals depicted both ways.

Re:geese

[omfglearntoplay]

I was thinking the same thing about wasted energy for the horizontal position, but then I thought about their tails. Do their tails go vertical also to save engergy? I can just see those huge dinosaurs now, tail held straight up like a house cat. Heh.

But really, I can't see them staying horizontal for long with their heads... even if the head weighed only a few pounds that would make it so much more energy wasted.

Re:geese

[Kozz]

(As the article notes) it's probably a lot harder to have the blood pressure to pump blood all the way up that column to the head. Blood pressure is one of the things they can't explain about their model. The article says, "Estimates of blood pressure also suggested that it would have been very difficult for sauropods to pump their blood up to such a height."

I propose the Stegosaurus Corollary: the long-necked dinosaurs had another heart halfway up the length of their neck!

Re:geese

[Red Flayer]

I think it's dangerous to try to compare a two legged winged creature to a four legged creature

Yes, I know it's dangerous, which is why I only make that comparison in a hardened secret laboratory. Last time I tried it, the explosion nearly blew through the 2nd-level blast enclosure.

Seriously, though, modern birds may be the closes living relatives to dinosaurs. And while I'd very strongly suspect that the long neck of geese evolved independently of the long necks of sauropods, it may be relevant.

(As the article notes) it's probably a lot harder to have the blood pressure to pump blood all the way up that column to the head.

Yes, this is an ongoing issue, and one of the primary reasons the position du jour has been lowered-head. But there is a ton we don't know about dino biology, and it is quite possible there are alternate means of pumping blood up the column (such as smooth-muscled vasculature that could help pump, especially in concert with valves like those in giraffes and other animals used to cut off blood flow temporarily. Or perhaps blood demands are low, and periodic lowering of the head could supply enough oxygen et al for survival. It's all conjecture... but it still makes me wonder if the net energy demands of maintaining a horizontal position would be greater than the demands of pumping blood and keeping the vertebrae vertical.

After reading it, the article's not as great as you think.

Hey, I never made a value judgment on the quality of the article. :) I just meant that typically the article being available for perusal guides the discussion somewhat... without TFA, the discussion tends to be more freeform and devolve into inanity quicker. Not that there's anything wrong with that.

Re:geese

[Anonymous Coward]

(As the article notes) it's probably a lot harder to have the blood pressure to pump blood all the way up that column to the head. Blood pressure is one of the things they can't explain about their model. The article says, "Estimates of blood pressure also suggested that it would have been very difficult for sauropods to pump their blood up to such a height."

I'm confused as to why they could not have had sub-hearts in their necks or a "distributed heart" where the neck muscles contracted around the arteries in a wave like motion to move blood up.

Slashdotted......

[cycler]

.....already.

I thought sites would have learned by now........

Oh maybe not :)

/C

Re:Slashdotted......

[X0563511]

Most of the time the site doesn't submit itself for slashdotting.

Someone sees it, goes 'neat' and pushed the button.

Maybe that posturing was due to head pressure

[davidsyes]

or high blood pressure or maybe they had thicknened cell walls up there...

Re:Maybe that posturing was due to head pressure

[Anonymous Coward]

maybe they had thicknened cell walls up there...

I'm no paleontologist, but I think they've already established that dinosaurs weren't plants, ergo no cell walls.

Re:Maybe that posturing was due to head pressure

[Anonymous Coward]

Well maybe they were bacteria.

Re:Maybe that posturing was due to head pressure

[DaveV1.0]

Or they had more than one heart.
Or a heart with more chambers in series

Re:Maybe that posturing was due to head pressure

[davidsyes]

Whatever it was, it must've been QUITE... manifold... hehehe

Straighten up and fly right!

[awb131]

That's going to kill my karma, but I thought it was funny.

Informed speculation

[MaXintosh]

This is all informed speculation - interesting, and it generates a testable hypothesis, but hardly revealing. There's a hundred different ways to go on the issue until they find impressions of soft tissue. The authors (of the paper, not TFA) hedge their bets heavily by saying that IF sauropods are directly comparable to extant taxa... a bet I wouldn't take myself, since sauropods seemed to form a morphoniche we don't see _appreciably_ filled in extant groups (obvious exception excluded).

For people who want their science undiluted, here's the paper: http://www.app.pan.pl/article/item/app54-213.html
Head and neck posture in sauropod dinosaurs inferred from extant animals
Michael P. Taylor, Mathew J. Wedel, and Darren Naish
Acta Palaeontologica Polonica 54 (2), 2009: 213-220

Re:Informed speculation

[Red Flayer]

This is all informed speculation

Aren't all theories?

since sauropods seemed to form a morphoniche we don't see _appreciably_ filled in extant groups

Please, stop making up words. We don't seen any morphoniche filled, because there is simply no such thing.

Thanks for the link, BTW, but the rest of your post is garbage.

Re:Informed speculation

[Anonymous Coward]

Please, get a clue.

http://ww2.coastal.edu/richard/VertZoo/CHAPTER%209.pdf

Re:Informed speculation

[MaXintosh]

Please, stop making up words. We don't seen any morphoniche filled, because there is simply no such thing.

http://www.blackwellpublishing.com/ridley/a-z/Morphospace.asp
And, for a word pedant, you seemed to have used the word 'Theory' incorrectly.
The nearby gradstudent seemed to understand me just fine. So.

Re:Informed speculation

[Red Flayer]

Oh please.

You googled "morphoniche" and came up with a single result?

And if you actually follow the link, the word doesn't even appear in the pdf document?

You, sir, are either lacking in sincerity or intelligence.

Re:Informed speculation

[Red Flayer]

I see. So suddenly, "morphoniche" is equivalent to "morphospace".

'Niche' is a generally-used term, which means something quite different -- it refers to a "place" in an ecology, as I'm sure you are aware.

Morphospace refers to a possible forms of an organism. Morphospace is a function of the organism, not of the ecology.

Since the organism in question does not currently exist in living form, it is a tautology that therefore the morphospace is unfilled.

So now, in addition to my assumption that you've made up words to sound like you know what you're talking about, you seem to be confused as to what the actual words mean.

The nearby gradstudent seemed to understand me just fine. So.

I understood what you were trying to say. That was not the issue I had. The issue is that you don't really know what you're talking about, and tried to use big words to compensate.

As for usage of the word theory... no, I meant it as defined. I did not mean hypothesis, although a hypothesis would also fit that criteria.

Re:Informed speculation

[Anonymous Coward]

It's a perfectly cromulent word. Its meaning is quite clear from both the spelling and the context. Jargon has to come from somewhere, and just because you refuse to understand it doesn't mean it's not useful. This is english we're talking about. There's no such thing as not having a word for something.

Re:Informed speculation

[Red Flayer]

The problem is that "niche" and "morphology" are two perfectly good words in current use, and his meshing of the two doesn't work because the roots describe different systems.

This is very similar to when non-techies refer to the CPU as the "hard drive". People without knowledge in a field, using real words from that field incorrectly, confuse the issue.

In this example, "niche" is the role an organism fills in an ecology; this is a function of the ecology. Morphology is the form or structure of an organism. This is a function of the organism. There is no "morphoniche" -- that assumes that there must be a place for a morphology in a given ecosystem; this is not a true assumption. Ecosystems are defined by functionality, not by morphology of the organisms (and yes, while morphology definitely impacts the niche an organism is capable of fulfilling, they are still terms that can't really be combined without distorting them ridiculously).

Finally, there is a different word he should have used, which is morphospace. This is the actual term used by people who know what they are talking about, and it refers to the possible forms and structures of an organism. He should have stated that we do not have an extant examples of organisms which have similar morphospaces as the giant sauropods.

Re:Informed speculation

[MaXintosh]

That was not the issue I had. The issue is that you don't really know what you're talking about, and tried to use big words to compensate.

Alas. You've caught me. I'm a naÃve fool who wraps myself in complex verbiage to cover my deep lack of understanding. I will now withdraw in disgrace.
Have a cup of coffee. Calm down.

Theories aren't speculation. Theories are well tested, well vetted informational organizational systems that generate (typically) multiple hypotheses. This is speculation, in the same way that my looking at flying squirrels can inform me about bats (in that maybe it can, but it's not a perfect relationship and the relationship needs demonstrated). The legitimacy of their conclusions based on their data is questionable. The authors even disclaimed themselves based on that, so it can't just be me who thought that.

Niche is not just used in an ecological context. There's an "Ecological Niche," but I've heard people talk about "Behavioural Niches," "Morphological Niche," I've even seen people talk about "Genetic Niches," to name just a few examples. Sometimes, the person is linking ecology in to whatever else they're talking about. Other times, they're just talking about an organisms set of values in a field of possible values. It depends on context. You see it in journals, and I've yet to see someone write an angry rebuttal that `so-and-so et al. doesn't understand the term niche` over it. If the idea was communicated, well that is the goal, isn't it?.

The wrong turn

[oldhack]

"...But 'our research [now] suggests that this view of sauropods is simply incorrect, based on everything we know about living animals,' he said."

Maybe they should have based it on what they know about dead animals, eh? Cuz all them dinos are dead, ain't it. I don't think these "researchers" are mucho bright.

yeah...

[Anonymous Coward]

looks like the web servers posture is all wrong.

until you CLONE THEM! - Nope

[Finallyjoined!!!]

Until there's a suitable time machine to enable you to go back and look for yourself.

Re:until you CLONE THEM! - Nope

[dzfoo]

By qualifying it as a "suitable" time machine, are you implying that we currently have time machines, albeit unsuitable to study dinosaurs?

        -dZ.

Re:until you CLONE THEM! - Nope

[the_humeister]

I don't know about yours, but my time machine only goes back to 4004 B.C.

Re:until you CLONE THEM! - Nope

[Finallyjoined!!!]

Nope, I qualify it as "suitable", if the control panel (or facsimile thereof) matches the pattern of my favourite shooting jacket :-)
Good point though :-P

Re:until you CLONE THEM! - Nope

[gnick]

Mine goes pretty well as far as you need it to.

The problem is that it only moves forward in time... And only at 1x...

Re:until you CLONE THEM! - Nope

[lgw]

A mirror is a time machine, for studying things in the past. To study dinosaurs, we'd need a really big mirror, really far away. We don't have a suitable one.

Re:until you CLONE THEM! - Nope

[morgan_greywolf]

"Suitable" time machine == capable of reaching speeds of 88.5 MPH and 121 Jigawatts of power.

Re:until you CLONE THEM! - Nope

[bb5ch39t]

mine seems to be going 1.1x and accelerating. Didn't a day used to be 24 hours? I'd swear it seems more like about 18 anymore.

Re:until you CLONE THEM! - Nope

[thedonger]

I don't know about yours, but my time machine only goes back to 4004 B.C.

Bummer...You got the "Old Testament" model.

Re:until you CLONE THEM! - Nope

[skine]

But does the Jurassic Park theme song flow better into the Back to the Future theme song, or the Doctor Who theme song?

Re:until you CLONE THEM! - Nope

[Zenaku]

You are off by half a mile per hour on the speed, and a factor of 100 on the power. Please travel back 30 years and prevent your geek card from ever being issued.

Re:until you CLONE THEM! - Nope

[Shimmer]

That's an interesting idea. Think about where the photons from the dinosaur age are now: 150 million light years from Earth, spread out in every direction. Gathering those photons so we can look at them now would be quite the achievement.

Re:until you CLONE THEM! - Nope

[Paolo DF]

also, it is Jigowatts :-)

Re:until you CLONE THEM! - Nope

[ppanon]

Yeah, there's newer Intel design models that go back to 80486 BC.

Re:until you CLONE THEM! - Nope

[Hurricane78]

It is gravity/speed-regulated. Just get near a black hole, or get really fast, and it will automatically speed up everything around you (but not you), from your point of view.

Einstein RULES! ^^

Re:until you CLONE THEM! - Nope

[Hurricane78]

Yeah. Because from what we know, it's physically impossible. (Except if something, like a big crunch compresses space really fast.)

Re:until you CLONE THEM! - Nope

[Hurricane78]

That's just the muffled audio of your old video cassette, which misses the heights of the sounds. ^^

Occams razor tells me

[Anonymous Coward]

The long necked dinosaurs simply tied their long necks into a knot whenever they needed to raise their heads for feeding and observations.

They had a symbiotic relationship with the horned dinosaurs who were needed for untieing the knots.

Coiled up on top

[hoggoth]

Come on people, CLEARLY the large long-necked dinosaurs kept their necks curled back and their heads resting on top of their backs.

Re:Coiled up on top

[morgan_greywolf]

Come on people, CLEARLY the large long-necked dinosaurs kept their necks curled back and their heads resting on top of their backs.

+5 Insightful

Re:Coiled up on top

[Tokerat]

While I doubt that they just left it there, it must have been great for itches.

Comment removed

[account_deleted]

Comment removed based on user account deletion

Re:I'm horny

[mrdoogee]

There's an app for that!

WTF

[dword]

dissension to the current prevailing wisdom on dinosaur posture

Why do these people write like you need a translation guide with you when you want to understand them?

Re:WTF

[Anonymous Coward]

Because they feel smarter that way.

Re:WTF

[P1h3r1e3d13]

Because their audience is fluent.
No sense in explaining every piece of anatomy in layman's terms when you're talking to paleontologists who already have specific words for them.

...Unless you meant the sentence you quoted, which isn't really sophistry. What do you want? "Disagreement" instead of "dissension?"

Re:WTF

[Anonymous Coward]

No translation guide needed, just that you went to school, and maybe have read a book in your life. If you really don't understand those 9 words, then smarten up, ignoramus. They're precise words chosen to convey nuance in meaning. But so sorry, you need a robust vocabulary to communicate at that level. If you didn't foster one in yourself, that's why you are feeling confused and worthless. I mean, that's why you ARE confused and worthless. So read. It makes you able to understand things, i.e. not dumb any more.

GOBBLES!

[SoundGuyNoise]

They all walked around like Gobbles the Turkey?

Matt Wedel must have missed Jurassic Park...

[G3ckoG33k]

"'For the last decade the reigning paradigm in palaeontology has been that the big sauropod dinosaurs held their necks out straight and their heads down low,' said co-author Matt Wedel"

What?! Matt Wedel must have missed Jurassic Park... In that movie, the brachiosaurs had their necks high as swans. What is he talking about?! That notion he is babbling about was killed 40 years ago...

As for the blood pressure, giraffes have the same problem. The water column. They solved it using finely meshed blood vessels. Oh, big wonder we don't fossils of those, yet...

Crap.

Re:Matt Wedel must have missed Jurassic Park...

[nyctopterus]

You've missed the last ten years of science on sauropod neck posture, obviously. That anyone could let such an alarming gap form in their knowledge is alarming!

Gravity...

[greywire]

I read an article once that claimed a solution to the issue of the blood pressure with such a long neck and other issues of size with the dinosaurs, and also why they became extinct, and if that werent enough it also explains why the earth *is* only 5000 years old and dating methods are wrong.

You wanna know what it was?

The universal constants like the speed of light, gravity, etc are changing over time! For instance, gravity is increasing, so back then the gravity was much less so there was no problem. As it increased, they died off for obvious reasons. And since the speed of light is changing, that effects our dating methods, etc.

It certainly was an interesting read...

Re:Gravity...

[twidarkling]

That sounds borderline psychotic. Considering scientists are doing experiments for hundreds of years and using those, expecting certain results, shouldn't the results not match what was expected, if those constants are changing? I mean, if the earth *is* only 5000 years old, a couple hundred years would be a significant enough chunk of time to figure it out.

Re:Gravity...

[drinkypoo]

You're assuming that the constants continue to change at a fixed rate.

No, I don't buy it either.

Re:Gravity...

[greywire]

It is psychotic. Because they say they don't believe in the science, but then try to come off sounding educated and using science to disprove the science.

What's really sad is all the people out there who believe them and never do any research themselves to see their pseudo science doesn't jive.

Re:Gravity...

[greywire]

You're assuming that the constants continue to change at a fixed rate.

No, I don't buy it either.

Though I will say that it seems as though the rate of ignorance in a population definitely is a constant, and that constant definitely is changing over time (unfortunately it seems to be increasing)

Re:Gravity...

[twidarkling]

Actually, no, I wasn't.

No matter how you run it, the fact that the Greeks were able to measure the circumfrence of the world thousands of years ago, to a high degree of accuracy, considering they used a couple sticks and math, if the constants of things like light were changing, that would mean they would necessarily needed different numbers in the same equations, or different equations with the same numbers, whether it was accelerating, decelerating, or changing at a fixed rate. But since the equations still work with our constants, the numbers have to still be the same. The illogicality of the arguement is just making my head hurt.

Re:Gravity...

[twidarkling]

Any chance you could point me in the direction of this? I'm actually interested in this now, if only for a good chuckle.

Re:Gravity...

[greywire]

I couldnt find it but I did find this equally offensive resource: http://www.parentcompany.com/handy_dandy/hder.htm

Enjoy.

Re:Gravity...

[Anonymous Coward]

Though I will say that it seems as though the rate of ignorance in a population definitely is a constant, and that constant definitely is changing over time

Then it's not a constant. (aka. I don't think that word means what you think it means).

Re:I'm horny

[greyline]

You're really a dude, admit it.

Giraffes

[White Flame]

Head-held-high seems to work fine for giraffes, though I'll be the first to admit that I don't know the rate of occurrence of heart problems in that species.

Re:I'm horny

[Anonymous Coward]

You're really a... i fucked your dead great grandmother!

Resurrected LINK

[Il128]

http://74.125.95.132/search?strip=1&q=cache:http%3A%2F%2Fwww.cosmosmagazine.com%2Fnews%2F2786%2Fdinosaur-posture-revised-again

Mod Parent +5 funny

[dtolman]

armchair science and movie science merged together to fight actual science. Who will win???

There is a theory

[G00F]

I recall reading about a theory where the moon impacted with earth, and earth gained it's core and the moon didn't have enough energy to escape, and ended up trap in orbit. Best I can find is Giant impact hypothesis, but I think it was a variation of this.

Something like that could explain mass extinction, and forcing more change with creating tides, seasons, etc. Not to mention, taking a mostly iron core could change gravity enough here where larger animals have a harder time. And look around at other planets, how many have a liquid cores, strong magnetic field, and active tectonic plates. I recall neither Mars or Venus, and so far they are the most like earth out of all other celestial bodies we have found.

Re:There is a theory

[dtolman]

I'm sorry, but reading this completely unrelated tangent, the only thing I could think of was:

Oh yeah, the important thing was that I had an onion on my belt, which was the style at the time.
They didn't have any white onions, because of the war. The only thing you can get was those big yellow ones...

Re:There is a theory

[aXis100]

I think a planet size object hitting the Earth is less of a "mass extinction and making it hard for large animals" event and more of a "completely liquifying the Earth and turning everything that was on it into molten lava goo" event.

Re:There is a theory

[ddimas]

Yes, it happened ~4-5 billion years ago. The Moon is the leftover debris from that event. The Earth itself did not form a solid crust for several million years afterwards, there is considerable evidence that the Earth lost it's entire atmosphere at that time. The present atmosphere is a combination of volcanic outgassing and cometary impacts. Any life that existed before that impact was completely destoyed.

two words: Octave Levenspiel

[Anonymous Coward]

Prof. Levenspiel has argued that atmospheric pressure was quite different during the days of the dinosaurs. Check it out:
http://levenspiel.com/octave/dinosaurs.htm

Dinosaur posture is bad

[Arslan ibn Da'ud]

because the dinosaurs didn't have a WiiFit!

ok i'll go back to my corner now.

Reproductive adaptation?

[Anonymous Coward]

I think they evolved so the sauropod babes could finally escape the 'Tyrannosaurus Punch' that was all the rage at the time

Re:I'm horny

[Dekker3D]

i know, gramps. you've told me a thousand times already.

Wrong format

[Anonymous Coward]

I got the pictures, but they're in some carved_in_stone format that my browser doesn't recognize. I'm looking for a converter...

assumption

[KingPin27]

FWIW This is simply assuming that all dinosaurs had their hearts in the right places ---
Doesn't anyone recall the Star Trek Movie where Kirk kicks the alien in the shin and it doubles over in pain cus he just happened to kick him in the nads?
As much as we know about dinosaurs it's quite possible that their hearts may have been elsewhere in their anatomy more better suited to pumping blood to places that needed it. But for the lack of an existing capillary diagram for a dino I might as well as just be speaking out my hat.

Re:It's fixed.

[chromas]

all that time has not been enough to fill in a footprint in the mud?

System Restore.

Re:I'm horny

[Tetsujin]

You're really a dude, admit it.

There was never any claim to the contrary, was there?

Or they might be wrong about environment

[Locke2005]

If they spent all their time in the water, they would not have needed a lot of musculature to support their neck and head. Why would a long neck be an evolutionary advantage in the first place? Either it helps for a) reaching food, b) being able to breathe while under water, or c) scoring with the opposite sex. For any of these, a more vertical neck posture would work better.

Generation gap

[Locke2005]

Perhaps it was only the teenage giant sauropod dinosaurs that had bad posture? Of course, these are the ones we would be studying, since they would have wound up in tar pits a lot more often. You know those reckless teens!

(Note to self: great idea for new cartoon series: teenage giant sauropod dinosaurs. Name each one after famous Impressionist artists. Have running joke about confusing Monet with Manet.)

Land dwellers?

[Anonymous Coward]

More likely they spent most of their life in the water where you would only see a bit of their head.

Giraffes Don't weigh 30 tons

[Anonymous Coward]

It's not that this isn't right, but it's daft to say "giraffes are OK so the diplodicus must have been fine with it too".

Blood pressure.

[Ungrounded Lightning]

(As the article notes) it's probably a lot harder to have the blood pressure to pump blood all the way up that column to the head. Blood pressure is one of the things they can't explain about their model. The article says, "Estimates of blood pressure also suggested that it would have been very difficult for sauropods to pump their blood up to such a height."

Presuming you do it all with the heart.

But it's similarly hard for a human to pump the blood back up from his/her feet. And if we stand still the blood WILL pool down there, the veins expand, and damage take place over a while. And if we don't flex our legs but stand still for a long time, enough blood will pool down there that we'll pass out. (This happens to people in the military when standing at attention for a long time when they're new to it and don't know the trick of flexing the legs occasionally.)

The way it works is similar to how some trees use wind power to pump sap up to the upper branches: With valves and swaying. We have valves in the leg veins. The intermittent squeezing of the muscles around the veins which go through them and/or stretching of the veins as the leg bends makes the vein/valve system act like a distributed heart, pumping the blood up past the next valve, then the one after that, etc.

Why shouldn't the long-necked dinosaurs have a similar mechanism for neck arteries? (If not actual additional heart-like devices partway up the neck - perhaps as an additional function of a gizzard?) These would be made of soft tissue and typically wouldn't make it into the fossil record.

Dinosaur Kama Sutra?

[Anonymous Coward]

Oh Cosmos...not Cosmo

And here I thought this was an article about postures in a dinosaur Kama Sutra.

Re:OMG!! Global Thinning!

[maxume]

Topical and timely:

http://www.scientificamerican.com/article.cfm?id=how-planets-lose-their-atmospheres

Regarding the life cycle

[Anonymous Coward]

Mine goes pretty well as far as you need it to.

Actually, the normal life cycle doesn't go as far as I need it to. There's an impediment called 'death' that keeps me from reaching the year when 'death from old age' has been eradicated.

What We Know

[DynaSoar]

Animals have valves in their veins to help regulate blood flow and pressure.

Present day long necked animals called giraffes can quickly raise their head from ground to high up or lower it as quickly without passing out or having a stroke, thanks to that regulatory device.

As a species, paleozoologists react to a threat (like publication precedence) by jumping from one precariously perched presumption to its complete opposite, all the while flying in the face of data from present day animals despite claims this was their basis for the jump.

Pray for the answer

[Anonymous Coward]

Religious people should just pray and when God tells them the answer, they can write it down in their blogs.

What? You say different people heard different answers?

Don't you realize!

[soldoutactivist]

That the Earth's gravity was less powerful back in the time of the dinosaurs?! That's how the necks could be so long! For reals, guys!

Sticking their neck out

[jandersen]

From the article it appears that the discussion only allows for two postures: either straight, vertical or straight, horizontal, both of which present some significant obstacles. The vertical model would require a huge heart, but the horizontal model would require some way of holding up a string of vertebrae against gravity, which would require either huge muscles or other things that would need to be supported by some skeletal structures that are missing, AFAIK. The model they suggest, I think, is something more like a swan's neck, which wouldn't be as tall (thus not requiring so high a blood pressure) and wouldn't require the extremely massive muscles, while still being as flexible as they seem to have been.

Author's response to points raised in the comments

[Mirk]

I am the Mike Taylor that is the lead author of this study. As pointed out by MaXintosh, the paper itself is freely available from the open-access journal Acta Palaeontologica Polonica, and we urge everyone who's interested to read it for themselves: we kept it short and made efforts to keep it comprehensible to intelligent non-specialists. It's at http://www.app.pan.pl/article/item/app54-213.html

Also, if the article pointed to here is Slashdotted, there is A LOT of other media coverage out there, including a TV interview, seven radio interviews, at least 25 online news sources and at least 14 blogs. Handily, we've linked them all from a page on our own blog, which you can find at http://svpow.wordpress.com/papers-by-sv-powsketeers/taylor-et-al-2009-on-neck-posture/

And maybe best, that blog -- Sauropod Vertebra Picture of the Week -- now has a sequence of seven posts explaining the research in more detail: these too are linked from the page I mentioned, and I think many Slashdotters will find them interesting.

To respond to a couple of specific points that have been raised in the comments here:

1. TinBromide though we compared only with giraffes, but in fact we compared with LOTS of animals, including birds, crocs, lizards, turtles, mammals and amphibians. The result were compellingly uniform. Similarly, MaXintosh wrote that "the authors (of the paper, not TFA) hedge their bets heavily by saying that IF sauropods are directly comparable to extant taxa". Well, sort of: we did rather nail our colours to the mast when we wrote "Can the habitual posture of extant amniotes be expected to apply to sauropods? Phylogenetic bracketing strongly supports this hypothesis as the neck posture described by Vidal et al. (1986) is found in both Aves and Crocodylia, the nearest extant outgroups of Sauropoda, as well as in the increasingly remote outgroups Squamata, Testudines and Lissamphibia."

2. eldavojohn asked "Why are we arguing over which position was the default when it's entirely possible that they utilized both positions" and noted that "There's plenty of pictures on Wikipedia [wikipedia.org] of the animals depicted both ways." It's true, of course, that animals can and do adopt different postures at different times: we make the point in the paper that sauropods had to be able to get their heads down low in order to drink, and could therefore pass through all intermediate postures. What we're talking about here is HABITUAL posture -- they way they spent their time when not actively doing something different. Geese can reach the ground, but they don't spend their lives that way.

3. A few people mentioned the problem of pumping blood up a high neck to the brain. We can't say too much about this at the moment as we're working on a paper on this subject and don't want to scoop ourselves. However, we do have good reason to think that the blood-pressure problem is not so severe as it's been depicted in Roger Seymour's work (going back as far as 1976, so we're well aware of it!) Sorry if that sounds evasive: hopefully we'll have a more convincing response for you within a year or so.

4. Finally, we want to be clear that we don't think our paper ends the debate. If anything, it re-opens it, as horizontal-to-dropping sauropod necks have been orthodox for the last decade or so. There's more work to do (but we're on the case!)

That's all for now -- hope it helps. If you have any more questions, you're welcome to ask, and we'll do our best to answer. The best place to do is probably over on Sauropod Vertebra Picture of the Week, as I and my co-authors each check that several times a day. http://svpow.wordpress.com/

Rating the Dinosaurs

[ciderVisor]

Rating the Dinosaurs, by Velcro (an old internet humour piece - not my work)

Brontosaurus

Huge beast. Ate only plants, but could crush a '93 Cabriolet with a single step of its titanic brontosaurus feet. Name means "Thunder Lizard" which is about as cool as you can get. Its only real drawback is that it didn't really exist.B+

Apatosaurus

This is what they're calling brontosauruses these days. Apparently they had some problem with the wrong skull on the wrong body--duh--and once they figured it out they had to change the name to "apatosaurus," which means "Deceptive Lizard." Personally I think they should have looked up the Latin for "Stupid Scientist." D

Dimetrodon

Looks like a gecko with a mohawk. Big sail on its back that they think attracted mates or conserved body heat. Actually, that's what scientists say about anything on an animal they don't understand. They could find evidence of an iguanadon with a ZZ Top beard and they'd say "the beard was probably to conserve body heat or attract mates." Which, come to think of it, is probably what ZZ Top uses them for. Anyhow, C

Tyrannosaurus Rex

Cool animal. Name means "Tyrant Lizard King." Cool. I wish my name meant "Tyrant Lizard King." Anyhow, we all know what makes this such a great dinosaur--it could completely eat you. Plus the little tiny forearms make it look like some demented nightmare beast from the fertile mind of Tim Burton. A+

Velociraptor

These guys got a lot of press from "Jurassic Park," but let's face it, they're pretty lacking. They couldn't even manage to eat two little kids, one of whom had only minutes before been turned into a toaster pastry. Sure, they got the hunter, but he was coming up with cute last words when he should have been running like a bunny. And then all three of them got totally worked by a baby Tyrannosaurus! Lame! D!

Stegosaurus

Two words: spiked tail. "Oh, so you're sneaking up behind me to eat my delicious body meats? WHAM! "Spikes! In the head! For you!" Plus it had I-am-an-industrial-monster plates on its back, which while probably for conserving body heat or attracting mates, were impressive-looking. A

Re:Rating the Dinosaurs

[whitroth]

About the brontosaurus vs. apatasaurus: it isn't bad enough that the brontosaurus has been extinct for 65M years, now they want to make the *name* extinct.

Besides, who wants apitty-patty-saurus? Give us back our Thunder Lizard!

        mark, chairman of the Committee to Save the Brontosaurus