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"Squishy Joints" May Have Helped Dinosaurs Grow To Giant Sizes

samzenpus posted about a year ago | from the bigger-they-are dept.

Science 56

benonemusic writes "A new study in the journal PLOS ONE suggests that dinosaurs reached gigantic proportions relative to mammals because of differences in their cartilage, making their joints squishier and able to sustain greater amounts of force. Other factors contributed to dinosaurs' larger sizes, including their lighter, air-sac-filled skeletons, and some researchers point out that the sizes of some dinosaurs and mammals were approximately equal, so anatomical differences between cartilage in dinosaurs and mammals may not directly explain why some dinosaurs grew to larger sizes."

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Wrong question (4, Insightful)

Joce640k (829181) | about a year ago | (#45231999)

"anatomical differences between cartilage in dinosaurs and mammals may not directly explain why some dinosaurs grew to larger sizes."

Anatomical differences are never going to explain "why", they can only explain "how".

"Why" is easy to answer - survival of the biggest.

Re:Wrong question (-1, Offtopic)

Anonymous Coward | about a year ago | (#45232297)

Not necessarily. "Why" could just be a radioactive mutation that happened to turn a lizard into godzilla. Mark my words, Tokyo tower will fall by the 2020 Olympics due to mutant lizards. I'm sorry though, if that were to actually happen I would not feel one ounce of sadness, I would be laughing my ass off from the irony and once that's out of my system then I would presumably feel bad for the victims and donate money to the "aaah! kore wa goduzira desu" foundation.

Re:Wrong question (1)

flyneye (84093) | about a year ago | (#45232483)

"Why" is seldom a helpful modifier with which to begin an interrogatory . It only deals with motives. It invites only speculation or lies , dependent on circumstance.
It would be easier to simplify that there was merely a "need", be it for competition, be it from different gravity, be it for, fill in the blank.
Unless one is privy to the cirumstances in realtime as a witness, "why" is only a guess and has no real place in science.
Far more profitable are; who, where, when, how and what, producing a trove of data, once satisfied.

Re:Wrong question (0)

Anonymous Coward | about a year ago | (#45232873)

Are you high? You sound high..maybe get off /. now?

Re:Wrong question (1)

Anonymous Coward | about a year ago | (#45233017)

Why should he get off /. for being high? It is, after all, a thread about joints.

Re:Wrong question (1)

flyneye (84093) | about a year ago | (#45242975)

Some of our greatest minds in history, altered their states of consciousness.
Entheogenic pharmocopia was present in and responsible for most of mans religions, carving the face of society since the stone age.
Marijuana has been shown to deal with many ills, from cancer to Parkinsons disease to pain relief , it is not unimaginable that it helps Joint conditions too.
It is not unimaginable that dinosaurs feasted on cannabis and benefited to various degrees.
No doubt, what's that chumps problem? Give him some fiber or something.

L. Ron Hubbard (1)

tepples (727027) | about a year ago | (#45244281)

Entheogenic pharmocopia was present in and responsible for most of mans religions

Then what kind of drugs was L. Ron Hubbard on to come up with Sci-Fientology?

Re:L. Ron Hubbard (1)

flyneye (84093) | about a year ago | (#45244395)

Being from Wichita, Ks, L.ROn could never find any decent drugs, but thanks to questionable ancestry and a little help from his family, he roasted right along on his own hormones and brain chemistry.
Family ever drive you crazy? Make a profit! Be a prophet! http://rsidd.online.fr/profit/ [online.fr]
I give you " The Profit" by Kehlog Albran

Re:Wrong question (1)

flyneye (84093) | about a year ago | (#45242927)

Hmmm no challenge to my premise , but a preoccupation with altered states. ( high x2 , get off )
Wants to know if I am high, indicates detection through a sense he could not possibly possess, then quasi mumbles something about "getting off slashdot now" as if he expects I am to anesthetize the readership. This isn't possible. Many software companies would eat rats , if only to figure out how to deliver that feature.
  You are a silly anon cow wanting to graze on grass,
If you shaved your head, you'd look half an ass.

Re:Wrong question (2)

Capt.Albatross (1301561) | about a year ago | (#45232553)

"anatomical differences between cartilage in dinosaurs and mammals may not directly explain why some dinosaurs grew to larger sizes."

Anatomical differences are never going to explain "why", they can only explain "how".

Agreed - this is sloppy reporting (mainly in the /. summary but also in the original). I think what they are trying to say is that this particular joint design, which evolved in smaller reptiles, later proved to be helpful in the evolution of giant dinosaurs - i.e., it was a sort of exaptation (formerly known as pre-adaption) in the sense that while this design's posited suitability for carrying large loads wasn't necessary when it evolved (the mammalian design was equally capable for animals of that size), it became a decider as evolutionary forces favored gigantism.

Re:Wrong question (1)

Sockatume (732728) | about a year ago | (#45232693)

Using "why" (implicitly "why can") rather than "how" is a very standard usage, both when asking these kinds of questions and answering them. I doubt anyone would actually read it in the anthropomorphising sense unless they were trying to win some sort of pedantry contest.

Re:Wrong question (3, Funny)

xevioso (598654) | about a year ago | (#45236683)

I agree. No one says to a 6 year old when they ask "Why is the sky blue" ...

"Do you mean why as in motives or did you actually mean how it is that the sky is blue? Please clarify."

because if you ask that, then they will say, "Why"

and then you are screwed.

Re:Wrong question (0)

Anonymous Coward | about a year ago | (#45243875)

But this why the sky is blue question cannot be answered fully. You can either go to the level of perception for your brain of blue or just a specific wavelength or the processes which produce it, basically immensely complicated question if you answer it fully which nobody 100% can explain. Of course ignorant people find explanation very easy.

Explaining sky color to a kindergarten student (1)

tepples (727027) | about a year ago | (#45244991)

Like the ripples in a pond, light is made of waves. Red light is long waves. (Make a gesture.) And blue light is short waves. (Make a gesture with more tightly spaced wiggles.) You remember the rainbow, right? The farther down the rainbow, the longer the waves. Now the sky lets the long red and yellow waves go straight from the sun to the ground, but the shorter blue and violet waves bounce around in all different directions. So when you look at the sky, you see the blue light that bounced off that part of the sky. Sunsets are red because sunlight has to go through so much sky that most of the violet, blue, and even green are scattered out before it gets to your eyes.

You'll learn the rest in school.

Re:Explaining sky color to a kindergarten student (1)

Sockatume (732728) | about a year ago | (#45258699)

So what you're saying is that the sky is blue because air is coloured a very pale shade of blue.

Re:Explaining sky color to a kindergarten student (1)

tepples (727027) | about a year ago | (#45260247)

Yes, and I've prepared the listener for further explanation of where the air gets that shade once the listener learns more about optics later in school.

Re:Wrong question (0)

Anonymous Coward | about a year ago | (#45232705)

"Why" is easy to answer - survival of the biggest.

Moar meat.

Re:Wrong question (3, Insightful)

Sockatume (732728) | about a year ago | (#45232709)

Given that "survival of the fittest" is an unguided process, isn't that also "how" rather than "why"?

Re:Wrong question (1)

Delarth799 (1839672) | about a year ago | (#45233817)

Survival of the biggest until that asteroid came along

Re:Wrong question (0)

Anonymous Coward | about a year ago | (#45235849)

The dinosaurs grew to such large sizes because the oxygen content and barometric pressure were much higher

Re:Wrong question (1)

Jeremiah Cornelius (137) | about a year ago | (#45235861)

Squishy joints in the morning
Squishy joints at night
Squishy joints, before squishy joints
And then squishy more...

Re:Wrong question (1)

reub2000 (705806) | about a year ago | (#45240085)

Well why where they so large? Where they endothermic, and the large body mass helped them conserve heat?

Re:Wrong question (1)

Darinbob (1142669) | about a year ago | (#45241031)

Ah yes, the Lehman-Brothersaurus, too big to become extinct.

They smoked squishy joints too. (5, Funny)

Anonymous Coward | about a year ago | (#45232003)

The huge joints that dinosaurs would have rolled would be quite squishy and sticky. They lit them at volcanoes of course. Which eventually led the the dinosaurs becoming too lazy and destructive(the joints would start forest fires) to serve their alien overlords so they were killed off.

Re:They smoked squishy joints too. (1)

Anonymous Coward | about a year ago | (#45232441)

The huge joints that dinosaurs would have rolled would be quite squishy and sticky. They lit them at volcanoes of course. Which eventually led the the dinosaurs becoming too lazy and destructive(the joints would start forest fires) to serve their alien overlords so they were killed off.

This is a cartoon I would pay to watch.

Re:They smoked squishy joints too. (0)

Anonymous Coward | about a year ago | (#45232495)

Well, I want some of what they're smokin'...oh, yeah, I guess I have some.....

Re:They smoked squishy joints too. (4, Funny)

drainbramage (588291) | about a year ago | (#45232989)

And that, Ladies and Gentlemen, is why they called it the Stoned Age.

Re:They smoked squishy joints too. (1)

Alsee (515537) | about a year ago | (#45236925)

It also explains why Fred and Barney were always cooking up colossally dumb ideas.

-

whoa man (1)

thoughtspace (1444717) | about a year ago | (#45232151)

... and the trees were purple and sky was bending through a tiny worm hole there we were all lead to utopia

Um... (0)

Covalent (1001277) | about a year ago | (#45232173)

Dinosaurs and mammals were about the same size? Didn't you just get done telling us that dinosaurs were much larger than mammals just 2 sentences ago?

Sheesh. What journal was this published in again? The Bible?

Re:Um... (2)

jabuzz (182671) | about a year ago | (#45232513)

No some, possibly even most dinosaurs are the same size as mammals. A small number of species of dinosaurs grew to be bigger than the largest land based mammals.

It's all bogus anyway as the largest known animal to ever exist is a mammal, namely the Blue Whale.

http://en.wikipedia.org/wiki/Blue_whale [wikipedia.org]

Re:Um... (1)

reub2000 (705806) | about a year ago | (#45240101)

The blue whale also doesn't have to support it's weight on it's limbs.

"scientists" (-1)

Anonymous Coward | about a year ago | (#45232211)

More ****ing dumb*** scientists who assume it is a certain way and only that way. That's right I talking to all you ***gots out there that think you know everything. You don't. How about starting with the fact that we don't know anything about the muscle tissue itself. It could have been a 1/4 of the weight and twitched 10 times faster. Not possible to these fuc**** though because they saw a computer animation once. To them it has to be like human, horse, etc. tissue, nothing else is possible in their world. Go **** yourselves. The same goes for the climate asshats out there, if it doesn't fit their pre-contrived model then it's not possible, not a factor, and will not be discussed again because it will make them look bad. FU

Re:"scientists" (0)

Anonymous Coward | about a year ago | (#45233957)

Judging from published research the problem nowadays is that the top priority for most scientists is no longer finding out the truth. Their priority is getting more funding.

So if you have some idea, instead trying to find out the truth immediately and doing a proper rigorous study/research, you try to spread out the process. So you go "let's see if it could have been this" try to get $$$ to fund that research, then later "think of another possibility", or "we should also test this as well" and get $$$ for that, and so on.

Basically I suspect the Feynmans, Einsteins etc of today are using their brains to extract more $$$ rather than extract more truths and insights from the universe.

Either that or most scientists nowadays are really that stupid and incompetent... You can see so many papers that are obviously flawed- have plenty of holes or have poor reasoning.

Then there's stuff like the recent "dolphin" one on Slashdot - the guy mentions dolphins but doesn't even find out how dolphins actually do what they do. So why does he bring dolphins up? The real reason is probably because dolphins = more visibility/marketability = more likely to get $$$.

"I was thinking to myself that dolphins should not be able to see fish with their sonar in these bubble clouds unless they are doing something very clever that manmade sonar cannot," co-author Timothy Leighton of the University of Southampton's engineering faculty told Agence France-Presse. "I sat and thought: 'If I was a dolphin what kind of pulse would I send out in order to see these fish in bubble clouds?' and then I decided on a pulse that was a positive and negative pulse."

By experimenting with different forms of acoustic signals, he found that a large pulse followed by a small one could reflect sound waves in such a way as to allow fish and bubbles to be easily distinguished. "We built a sonar that did this and took it out to sea and it worked beautifully," Leighton says, though he adds that he isn't sure this is how dolphins detect their prey.

Critical thinking missing (4, Interesting)

abhisri (960175) | about a year ago | (#45232241)

Evolutionary paths.

Insects on average are smaller than most mammals. Mammals too come in all sizes.

Analysis of air trapped in amber fossil shows that oxygen ratio in that period was higher, which may have permitted evolutionary path of such giant creatures.
http://minerals.cr.usgs.gov/gips/na/amber.html [usgs.gov]

Squishy joints? Considering how cause and effect get frequently confused, it seems more likely that the joints may have became "squishy" in order to support the larger size permitted by the oxygen-rich high-metabolism environment, not necessarily actually the cause.

Re:Critical thinking missing (3, Informative)

Joce640k (829181) | about a year ago | (#45232411)

Insects don't have lungs or a circulatory system. Their size is limited by how fast oxygen can diffuse through their internal goo.

Re:Critical thinking missing (0)

Anonymous Coward | about a year ago | (#45233005)

But they grew much larger before more complex animals took over the ecological niche of large creatures

Re:Critical thinking missing (1)

samoanbiscuit (1273176) | about a year ago | (#45243439)

Keep in mind that hundreds of millions of years of extinctions and adaptive radiations have taken place between then and now. It's not only a question of whether insects can exist at the larger sizes they once grew to, but also whether they'd be competitive enough to take back their former ecological niches from the current incumbents. To use a tech analogy, it's like asking whether a flip phone can dominate the premium phone market in 2014, because they once dominated it in 2005.

Judging from the range and distribution of insects alive in the present, it seems that for most insects, small size and rapid reproduction are the way to go for them. Their body plan, with it's less efficient circulatory system, and less complex brains, seem to put them at a disadvantage if they began to grow larger. Remember that there are a vast array of mammals and birds that specialize specifically in preying on insects.

Re:Critical thinking missing (1)

GodfatherofSoul (174979) | about a year ago | (#45234959)

But, is that correlation or causality? Do oxygen rates really need to be that much higher to grow that large. Sherpas get by with the same biology, just way more hemoglobin (?) in their blood to exploit lower oxygen levels at altitude. And, your body would quickly adjust as well.

Or were the oxygen levels just an artifact of the arms race of trees trying to outgrow the herbivores? I have no clue, just speculating.

Re:Critical thinking missing (1)

quantaman (517394) | about a year ago | (#45241449)

We're not operating at the fringes of the size limit so our biology can adapt more easily.

A more relevant question might be what limits an Elephant's size. Would a slightly larger elephant have trouble extracting enough oxygen from the atmosphere to survive?

Re:Critical thinking missing (0)

Anonymous Coward | about a year ago | (#45235275)

"Analysis of air trapped in amber fossil shows that oxygen ratio in that period was higher, which may have permitted evolutionary path of such giant creatures.
http://minerals.cr.usgs.gov/gips/na/amber.html [usgs.gov] "

And science backs the Bible yet again. Pre Flood/Noah higher oxygen in the air. After the Flood the oxygen levels decreased. Don't believe? Good place to start. http://www.creationworldview.org/

Re:Critical thinking missing (0)

Anonymous Coward | about a year ago | (#45236849)

some facts missing too

Dinosaurs (and Birds) evolved at the end of the Permian, when atmospheric SO2 was high and O2 was low. they have a "double" lung circulation system, much more efficient than mammals' and reptiles' lungs.

so they prospered in the Triassic and Jurassic, and when O2 levels raise they made the best of it.

Re:Critical thinking missing (1)

quantaman (517394) | about a year ago | (#45241395)

I'm still waiting for the scientifically accurate remake of Jurassic Park where the dinosaurs are all lying on the ground gasping for air.

Because Gravity was lower - See Expanding Earth (0, Funny)

Anonymous Coward | about a year ago | (#45232327)

Some of the best, brightest but ignored scientists in the world already know. The sun constantly bombards us with new energy which is converted into other materials. Over millions of years, this results in an increasing mass of the earth and and expanding earth. When Dinos were around, the earth was significantly smaller, and that's why not only Dinos but Trees were significantly larger back then. Gravity was lighter. Just look what happens to an Astronaut in zero gravity. They usually gain a couple of centimetres on their return. Imagine if the earth suddenly only gave us half the gravity. We'd all gradually get larger even in our own lifetime.

Re:Because Gravity was lower - See Expanding Earth (0)

Anonymous Coward | about a year ago | (#45232565)

"Some of the best, brightest but ignored idiots in the world already insist they know."

FTFY.

Easy Food Helped Dinosaurs Grow to Huge Size (1)

BoRegardless (721219) | about a year ago | (#45232991)

Come on now. There had to be one hell of a lot of easily obtained food in massive fields of easily reached, easily mouthed leaves and stalks for these huge vegetarians to exist (we'll ignore the tiny guys.) There also had to be a limited number of viable predators. Dinos also must have been able to grow fairly fast to reach those sizes within what could be considered a likely lifespan.

How come nobody talks about these other requirements? In other words there is a whole ecosystem and genetic system that conspired to let the huge dinosaurs exist.

Lower Gravity (0)

Anonymous Coward | about a year ago | (#45233029)

taht is why:
Earth itself was younger and smaller by then - and the surface gravity was far lower, thus allowing for gigantic creatures.

http://www.dinox.org/expandingearth.html [dinox.org]

How bigger? (0)

Anonymous Coward | about a year ago | (#45233165)

It has always been a bit of a mystery as to how some of the largest land animals the world has ever essn managed to survive their size.
          First off, there was a higher percentage of Oxygen to Nitrogen ratio prior to the KT Impact (As well as the Siberian Traps). This would allow for more energy to be available to the muscle tissues for more effecient movement. However; While the legbones of some of the largest brachiosaurs were truely impressive, the mass ratio and structural capibilities, even allowing for hollow bones, simply stretches credulity.
          A thought had occured to methat seems on the face of it, absolutly bizaar, but it would explain the massive sizes of these creatures as well as allow for the tremendous amount of heat that they would normally generate.
          Internal Methane Bladders. It occured that, as these creatures were herbivores, they would, by their very nature, generate huge amounts of Methane, should their digestive tracts divert some of the gas to storage bladders, around which a complex vascular system had grown, not only would would the lift from these bladders partially compensate for their tremendous size, but also help to regulate their body temperatures during the day and overnight. There is already an analog to this existing in most species of fish that control their bouyancy via internal airbladders.
          Admittedly, this would not explain WHY these creatures grew to such great sizes, but it would explain HOW they survived at such great sizes.

Just a hypothsis...

Jason

Squishy Joints? (0)

Anonymous Coward | about a year ago | (#45233969)

Dude! Wait, what?

More government lies! (1)

Dcnjoe60 (682885) | about a year ago | (#45234399)

All these years, the government has been telling us that smoking special joints will stunt our growth. Now we find out that special joints led to the dinosaurs growing to extraordinary sizes!

What about the small? (0)

Anonymous Coward | about a year ago | (#45234901)

What about the small Dinosaurs? Did they have "Squishy Joints" also?

Hmmmm .... (1)

gstoddart (321705) | about a year ago | (#45235249)

Other factors contributed to dinosaurs' larger sizes, including their lighter, air-sac-filled skeletons, and some researchers point out that the sizes of some dinosaurs and mammals were approximately equal, so anatomical differences between cartilage in dinosaurs and mammals may not directly explain why some dinosaurs grew to larger sizes.

I thought the much larger concentration of oxygen in the atmosphere was supposed too have been a factor, and they'd never have been able to grow that big in our current atmosphere.

Oxygen? (0)

Anonymous Coward | about a year ago | (#45235261)

I always thought that the size attained by the dinosaurs was a combination of high levels of O2.

mod d0wn (-1)

Anonymous Coward | about a year ago | (#45235319)

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Dinosaurs got bigger because... (0)

Anonymous Coward | about a year ago | (#45236751)

Some really clever little monkeys weren't around in the mesozoic to stab everything larger than a bug to death.

Mammals were well on their way to getting huge before we killed all the big ones off.

Fact. (1)

jfisherwa (323744) | about a year ago | (#45239195)

- Grow large, forcing an optimization of weight
- Wrong move! Environmental pressures prefer small
- Small and optimized for weight
- Oh shit, we can sort of fly!
- ???? = Ad views
- Profit

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