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New Analysis Shows Dinosaurs Not As Heavy As Previously Believed. 155

Posted by samzenpus
from the he's-not-heavy-he's-my-dinosaur dept.
Cognitive Dissident writes "Discovery.com has an article on a new study using computer modeling to estimate the actual amount of flesh needed to cover the skeletons of dinosaurs. Based on a comparison with modern animals, it indicates that these animals could have weighed dramatically less than has been previously estimated. 'A huge Brachiosaur, once thought to weigh 176,370 pounds, is now believed to have weighed 50,706 pounds.' That's only about two-and-a-half times the weight of a modern African elephant. If other evidence can be reconciled with this, many estimates of the ecosystems dinosaurs lived in will also have to be revised."
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New Analysis Shows Dinosaurs Not As Heavy As Previously Believed.

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  • Dino Booty (Score:5, Funny)

    by pd0x (2618075) on Wednesday June 06, 2012 @11:19PM (#40240439) Homepage
    Dinosaurs. Not heavy, just big boned.
    • Dinosaurs. Not heavy, just big boned.

      T-Rex just has to realise that these low carb diets are just a fad, and that it cannot get by on just one brontosaurus a week.

      • by GoodNewsJimDotCom (2244874) on Thursday June 07, 2012 @12:28AM (#40240801)
        Finally scientific evidence comes out saying it is all because of their genetics. We should be ashamed of all the years we've been calling dinosaurs old and fat.
        • Re: (Score:2, Redundant)

          by a_hanso (1891616)
          I'm waiting for the creationists to seize on this to claim that maybe dinosaurs aren't as real as previously believed.
          • Dammit Bill... [imageshack.us]
          • by Immerman (2627577)

            Really! I mean if new evidence suggests that 72% of our concept of a Brontosaurus never actually existed, why should we believe that the other 28% ever did? Obviously the scientists are just making this junk up, and the universe popped into being fully-formed last Tuesday, just in time for tea.

        • by flyneye (84093) on Thursday June 07, 2012 @07:29AM (#40242577) Homepage

          "Discovery.com has an article on a new study"

          The problem with the gullibility of the world are those willing to swallow that a "study" constitutes research bearing evidence.
          Bad news, Jim, the study, is a quicky look at an information set for the purpose of determining if further research ( an actual search for evidence) is worth throwing money at. A strange animal , the study, frequently found near bored professors trying to busy a classroom has also been sited being unethically molested by corporations and governments for the purpose of manipulating the populace into beliefs advantageous to their purposes. This modern "study" device is actually descended from a useful tool that used to be defined by rules designed to make it scientifically useful; like polling a random 10% of your info pool, remaining an unbiased observer and including findings that may be contrary to the benefactors goal. Compare and contrast to todays "study" used to sell you everything from soap to political party, Polling targeted groups, interacting to manipulate outcomes and of course only keeping what could be construed as useful to a benefactors cause.

          Caveat Geekor!

        • by mcgrew (92797) *

          We should be ashamed of all the years we've been calling dinosaurs old and fat.

          Bullshit, maybe the rest of the dinasaurs were fit and trim, but my ex-wife is certainly old and fat.

    • Just fluffy.
    • by rolfwind (528248)

      Fred Flintstone tells me that they're simply fishing for an excuse to jack up the price of bronto burgers.

  • by fotoguzzi (230256) on Wednesday June 06, 2012 @11:37PM (#40240561)
    Is enough known about footprint formation to estimate the mass of the creature that made them?

    [Sorry if this is a repeat. I do not see my first attempt.]
    • by Telvin_3d (855514)

      I suspect that the margin of error for footprints would be even higher. After all, many, many uncontrollable and unknowable external effects would go into the final fossilized footprint.

    • by wvmarle (1070040) on Thursday June 07, 2012 @01:34AM (#40241071)

      I doubt a footprint can give any useful measure of the weight of the animal that made it.

      Too many variables. Walking speed and method will influence it, as it affects the impact between foot and soil and the time the foot is pushing down on the soil. Exact original soil content (water content and particle size). How deep the soft layer of soil really was.

    • Haven't read article, but if you know what the rock is made of, you probably know what the mud was made of. Then, you can probably estimate impression depth on a scale with viscosity.

      • by Immerman (2627577)

        Yes, but you have absolutely no idea how much water was in it when the footprint was formed, and only the vaguest idea of the size and kind of organic molecules present (you know, all that stuff that makes it dirt rather than sand)

  • by Anonymous Coward on Wednesday June 06, 2012 @11:39PM (#40240571)

    pounds? for a minute there I thought we were talking sience...

    Let's make the African elephant unit a standard.

    • by Anonymous Coward on Wednesday June 06, 2012 @11:49PM (#40240619)

      Even when talking "sience", there's nothing wrong with using pounds and ounces.
      This is a US site, and science-savvy Americans understand both systems of units.

      • by Kapiti Kid (1003167) on Thursday June 07, 2012 @12:55AM (#40240925)
        Except that most people in the world, including myself, have no way to relate these medieval measurements to anything meaningful.
        • by drkim (1559875) on Thursday June 07, 2012 @01:56AM (#40241165)

          Sorry Kapiti, that should have read:
          "A huge Brachiosaur, once thought to weigh 12597.9 stone, is now believed to have weighed 3621.9 stone."

        • Except that most people in the world, including myself, have no way to relate these medieval measurements to anything meaningful.

          Okay, so just substitute newtons for pounds - multiply by 4.45. That'll give you the proper SI unit for weight...

          So, 176,370 pounds = 785,000 newtons (approximately, can't understand why TFA gives weight to the nearest pound)

          And, 50,706 pounds = 226,000 newtons.

        • by Random2 (1412773)
          Oh, yes you do. it's called don't be a twat. [google.com]

          Seriously, it's hard to take you as anything but a troll for raising a fuss over such a simple conversion. If you can't understand the units, then convert them to something you can.

          In fact, in the time you spent griping about this, you could have made the conversion and then posted it for the relevant slashdot audence to see! And that would actually be doing something useful.
        • by kidgenius (704962)
          C'mon dude, divide by 2 and you will be close enough. If you can't do that math, maybe you shouldn't be on this site.
      • by RockDoctor (15477)

        This is a US site,

        Ah, you're logged into slashdot.org.us ? Yet bizarrely when I'm logged into the international site (slashdot.org), I can also see your comment.

        It seems that you've been contaminating your precious bodily fluids by posting to an international site, when you thought that you were posting to a Good Ole All 'Merkin site. My commiserations. I suggest a wire brush and Dettol [wikipedia.org] for decontaminating your fingertips and retinas.

    • Precision (Score:5, Informative)

      by Convector (897502) on Thursday June 07, 2012 @12:51AM (#40240901)

      The masses given equate to 80000 kg and 23000 kg respectively. Or 80 and 23 (metric) tons. Two significant figures. Not more. No doubt those were the numbers originally supplied by the scientists, and the author of TFA converted it to pounds for the typical American reader without understanding how precision works. This happens all the time in the popular press. Clearly you can't estimate the weight of a creature you've never seen to within 1 lb. Your standard human's weight fluctuates by more than that over the course of a day.

      • by drinkypoo (153816)

        Clearly you can't estimate the weight of a creature you've never seen to within 1 lb.

        Oh, you can estimate it to within 1 lb, all right, but your estimate will almost certainly be wrong. ;)

      • by Anonymous Coward on Thursday June 07, 2012 @04:33AM (#40241813)

        "This happens all the time in the popular press. Clearly you can't estimate the weight of a creature you've never seen to within 1 lb"

        I went to the museum and saw a big Tyrannosaurus skeleton and I asked the guide how old it was.
        He said: "75,000,013 years."
        I said: "Wow! Since when do they know the age up to the year?"
        He said: "Well, it was 75,000,000 years old when I got this job and that was 13 years ago."

  • Not necessarily (Score:5, Informative)

    by Opyros (1153335) on Wednesday June 06, 2012 @11:43PM (#40240591) Journal
    This write-up [discovermagazine.com] gives reasons for doubting that the new technique does show dinosaurs were significantly lighter than previously thought.
    • Re:Not necessarily (Score:5, Insightful)

      by wvmarle (1070040) on Thursday June 07, 2012 @01:55AM (#40241163)

      The huge difference in results from this technique and older estimates made me sceptical already.

      If one method comes to say 80 tons, and another to say 70 tons, then I say sure, both sound reasonable, and not too far away. But if the other method comes to 23 tons, then I start to wonder what is wrong. One of the methods is wrong for sure, just the question is which one.

      Interestingly the article you link to says that the weight of this particular dino was previously estimated at just over 23 tons. Almost exactly what the new method predicts. The 80 ton weight is suggested to be an old figure, and already long since relegated to the history books. The value in the new method is not as much in that the dinos get a lighter weight, it's that it confirms current weight estimates, and will allow for much faster and cheaper measurements on other dino skeletons.

      So while your comment is technically correct, it's also slashdot-style suggestive into suggesting that the new technique is wrong, while in fact the new technique confirms the consensus weight of just over 23 tons for the animal. And that would also suggest that current ecosystem calculations are already done with the lighter weight - making the summary even more sensationalist.

      • Re:Not necessarily (Score:4, Informative)

        by flyingsquid (813711) on Thursday June 07, 2012 @10:46AM (#40244379)
        The 80,000 kg estimate has long been thought to be wildly inflated, and that estimate comes from a study published in 1962. A more recent estimate, published in 1997, gave a mass of 31500 for the Berlin brachiosaur, and a study published in 2009 estimated the mass of this specimen at 23000 kg... just 300 kg more than this study. So they haven't actually shaved off much weight with this latest version. It is an interesting new technique, if you have a skeleton to work with. But it's not terribly practical. Only a handful of dinosaurs are complete enough to make skeletal mounts and have actually been mounted. And we already have ways to estimate their mass- either make a model and dunk it in water to figure out the displacement (a method that's been around since the time of Archimedes) or use the diameters of the limb bones to estimate mass (as load-bearing structures, limb bone dimensions are very tightly correlated to total mass). It's nice to see previous estimates verified, and to have some constraints on how much meat to add onto the skeleton, but I don't think this technique is as big an advance as the authors claim.
      • by dylan_- (1661)

        Did you just -- in the same comment -- show yourself sceptical of the new technique, provide some evidence for your scepticism and approval for the old, then cast doubt on the old technique and provide evidence why the new was superior to the old?

        Sir Humphrey?

        • by wvmarle (1070040)

          As a scientist you must be sceptical about both techniques if a big difference is found. Try and find evidence both for and against each technique, and see which one is better.

          In this situation, you start with method 1, which at the time is considered a good method. Then you come with method 2, and find wildly different results. Then you know that one of them must be wrong - the question being which one. Having four different methods, three giving similar results and one giving a very different result, is a

  • 60s "science"? (Score:2, Interesting)

    by Gordo_1 (256312)

    Even without computer simulations, I imagine they'd compare dinosaur skeletons to that of elephants, horses, giraffes, rhinos and even birds (which are supposed to be descended from the dinosaurs) to develop some reasonable bone mass or skeletal girth to weight ratios, no? Off by a factor of 3 1/2 seems ridiculous, even if we're talking research that was done in the 60s.

    And in response to myself... According to the article (which I just skimmed), a common method was to take an artist’s reconstruction

    • by Anonymous Coward

      And you wonder why people don't trust science...

      If that's the problem, then why trust medicine, which had such fun with leeches, phrenology and humours!

      There was a time arsenic and mercury were the cure for what ails you!

      Which the doctors justified by saying they had no repeat complaints!

    • Re:60s "science"? (Score:4, Informative)

      by Chris Burke (6130) on Thursday June 07, 2012 @01:31AM (#40241059) Homepage

      Off by a factor of 3 1/2 seems ridiculous, even if we're talking research that was done in the 60s.

      I don't think that research was done in the 60s, and I certainly don't think this is up-ending the previous best estimate by such a large factor. I'd bet that guess was made closer to the time Brachiasaurus was discovered in the very early 1900s, and that's why it says "once thought" and "estimates have been as high".

      WP suggests the most recent estimate (from 2009) was 28.7 metric tonnes.

      While this new figure is still appreciably lighter, it doesn't make it sound as shocking to use the most recent estimate as the comparison point, does it?

    • Re: (Score:2, Interesting)

      by Anonymous Coward

      It's not ridiculous, because: A) reconstructing skeletons is challenging enough (look at the historical changes in understanding of the posture of dinosaur hips), B) reconstructing muscle mass, bone internal structure/density, lung volume, etc. is even more challenging, and C) the 80 tonnes estimate for Brachiosaurus was an upper limit, not the median estimate (which was closer to 40 or 50 tonnes). Being off by a factor of 2-3x is not ridiculous given the significant uncertainties, and you can't blame arti

      • Yes 80 tons is what I was taught at school in the 60's but even then they had to have the big ones permentently wading in water to support that weight, canivorous versions were lighter but still portrayed with all the speed and agility of a giant land turtle. A book at the library talked about the possibly of dinosaurs still existing in the tropical forests of Venus!
  • by rossdee (243626) on Wednesday June 06, 2012 @11:45PM (#40240599)

    "A huge Brachiosaur, once thought to weigh 176,370 pounds, is now believed to have weighed 50,706 pounds."

    Those figures seem to imply they knew the weight to an accuracy of a few pounds, why don't they 175,000 and 50,000 pounds?

    Did they measure the depth of the footprints?

    While we are mentioning dinosaurs, a sad farewell to the Author of "A Sound of Thunder" Rest in Peace Ray

    • by quacking duck (607555) on Wednesday June 06, 2012 @11:49PM (#40240621)

      Because the original weights were in kilograms (80,000kg and 23,000kg respectively), and Discovery helpfully converted to the Imperial system for its American audience without properly sourcing the original figures.

      • by gman003 (1693318)

        Ah, that's exactly what I was going to guess. Anytime I see a figure with far more significant digits than it ought to, I suspect a unit conversion done improperly.

      • When you're dealing with numbers that big and that rough why not just divide by 1000? A megagram is a ton, near enough.

    • 80 tonnes versus 23 tonnes. Looks like someone just ran "80 tonnes in lb" through Google.
    • The original estimate could've been in 5879ary, and it only looks like there is more than 1 significant digit because of a sloppy conversion for printing purposes.

    • by symbolset (646467) *
      Anybody who had a lot of faith in footprint evidence for mass had not stepped in enough kinds of mud.
  • by lurgyman (587233) on Wednesday June 06, 2012 @11:51PM (#40240627)
    When you converted 80,000 kg and 23,000 kg to pounds, it was swell of you to convert 1-2 significant digits to 5. I for one enjoy the round-off noise in the last 3 decimal places - it has premium aesthetic value. I bet those dinos probably thought the same way; losing weight must have been less depressing in terms of losing 2 pounds rather than 0.001%. On second thought, I barely know my own weight to 3 digits...
  • by slashmydots (2189826) on Wednesday June 06, 2012 @11:51PM (#40240633)
    This is just like all other science. The most sensation, impressive sound stats that's backed by "real sounding" science wins. Impossibly heavy lizard vs reasonably, logically sized lizards. Let's go with the freaking lizo-tank. Mathematical error or magical substance we can't see or measure = entire 1 hour specials on dark matter. One of millions of things we have flying around up there vs careless aliens visiting...well that's alien UFOs of course. I think that might even have its own channel actually. This really needs to stop.
    • by FrootLoops (1817694) on Thursday June 07, 2012 @02:21AM (#40241257)

      I hate it when people deride dark matter without having the first clue about it. Neutrinos interact only through the weak force and gravity. Maybe another particle interacts only through gravity. No EM emissions would make it dark, no strong or weak interactions would make it essentially undetectable on earth. It would only show up on astronomical scales. Oh, and humans (who are very biased towards the types of particles we're made of and interact regularly with) would think the whole thing was voodoo.

      And maybe not. There are numerous explanations for dark matter ranging from various forms of exotic matter to fundamental problems with existing theory. So far there are no clear winners. Making a "mathematical error vs. magical substance" dichotomy is so oversimplified it would be better for you to simply be quiet on this topic.

      • Making a "mathematical error vs. magical substance" dichotomy is so oversimplified it would be better for you to simply be quiet on this topic.

        This ... is ... SLASHDOT!

  • by AlienIntelligence (1184493) on Thursday June 07, 2012 @12:11AM (#40240727)

    That is a hell of a long time to miss that concept. We wasted a lot of time
    and resources predicting a lot of things that are off by several magnitudes
    believing that they were of a different weight.

    There will be a flood of new data from related sciences following this. And
    probably a number of other studies trying to disprove it.

    -AI

    • by ceoyoyo (59147)

      Assuming you mean "orders of magnitude," you might want to familiarize yourself with what that actually means. 80 tonnes and 20 tonnes are not different by an order of magnitude. Not even one.

      Also, the 80 tonne estimate seems to be from the distant past. More recent estimates are in the high 20s, so the difference with this estimate isn't even 50%.

      • Assuming you mean "orders of magnitude," you might want to familiarize yourself with what that actually means. 80 tonnes and 20 tonnes are not different by an order of magnitude. Not even one.

        Also, the 80 tonne estimate seems to be from the distant past. More recent estimates are in the high 20s, so the difference with this estimate isn't even 50%.

        Assuming you mean "orders of magnitude," you might want to familiarize yourself with what that actually means. 80 tonnes and 20 tonnes are not different by an order of magnitude. Not even one.

        Also, the 80 tonne estimate seems to be from the distant past. More recent estimates are in the high 20s, so the difference with this estimate isn't even 50%.

        Man, you are a dick... lol

        If I would have fuckin meant orders of magnitude, I would have fuckin said it.

        I didn't say it, cause "orders of magnitude" is incorrect, as you brilliantly
        pointed out, after you changed the meaning of what I said by adding words.

        magnitude [mægntjud] n.,
        1. relative importance or significance
        2. relative size or extent
        3. (Mathematics) Maths a number assigned to a quantity, such as weight, and used as a basis of comparison for the measurement of similar quantities

        Yes, when you add

        • by ceoyoyo (59147)

          Oh, okay, so you didn't make a typo, you just don't understand how to use common words. You can't "be off by magnitudes." It's not a countable item.

          Nice try at covering though.

  • by BlueTak (1218450) on Thursday June 07, 2012 @12:23AM (#40240781)
    Was it a european or an african brachiosaur ? Do you think it could carry coconuts ?
  • I mean, their bones were made of stone!
  • He ain't heavy....

    ...he's my brachiosaur....
  • While we're at it, are they closer to an explanation on why birds tweet and chirp,snakes and lizards hiss and their dinosaur ancestors are always shown in movies roaring like lions?

  • Here it is for people that can't make sense of that pound unit, which value depends on country and time period:

    New study estimates that the Brachiosaur, once believed to weigh about 80 tons, may actually have only weighed 23 tons.

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