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New Analysis Shows Dinosaurs Not As Heavy As Previously Believed.

Posted by samzenpus on 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."

18 of 155 comments (clear)

  1. Dino Booty by pd0x · · Score: 5, Funny

    Dinosaurs. Not heavy, just big boned.

  2. What about footprints? by fotoguzzi · · Score: 5, Interesting

    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.]

    --
    Their they're doing there hair.
    1. Re:What about footprints? by wvmarle · · Score: 4, Informative

      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.

  3. Elephant metric system by Anonymous Coward · · Score: 5, Funny

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

    Let's make the African elephant unit a standard.

    1. Re:Elephant metric system by Anonymous Coward · · Score: 4, Informative

      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.

    2. Re:Elephant metric system by Kapiti+Kid · · Score: 4, Insightful

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

    3. Re:Elephant metric system by drkim · · Score: 4, Funny

      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."

    4. Re:Elephant metric system by Onkel+Ringelhuth · · Score: 4, Informative

      > You don't see ten meter-kilograms of torque listed in a technical manual anywhere across the globe, do you?
      Nope. The unit is Newton-metres. Now, does anybody want to argue about standardisation of spelling?

    5. Re:Elephant metric system by hanabal · · Score: 4, Interesting

      Interestingly enough 50,706 pounds is amlost exactly 23,000 Kg. Leading me to believe that the Kg was the original unit of the study

  4. Not necessarily by Opyros · · Score: 4, Informative

    This write-up gives reasons for doubting that the new technique does show dinosaurs were significantly lighter than previously thought.

    1. Re:Not necessarily by wvmarle · · Score: 4, Insightful

      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.

  5. Re:Accuracy of estimate? by quacking+duck · · Score: 4, Informative

    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.

  6. Dear discovery channel, by lurgyman · · Score: 4, Informative

    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...

  7. Re:I blame yo-yo dieting myself by GoodNewsJimDotCom · · Score: 4, Funny

    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.

    --
    God spoke to me
  8. Precision by Convector · · Score: 5, Informative

    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.

    1. Re:Precision by Anonymous Coward · · Score: 4, Funny

      "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."

  9. Re:And geeks wonder why Joe Six-pack disbelieves.. by Chris+Burke · · Score: 4, Informative

    10/10 for using the ol' "science is like Religion because they claim to have Truth and banish those who disagree with their Orthodoxy" line in an article about scientists at a major research university up-ending the "orthodoxy" and publishing their "heresey" in a Royal Society publication. I love this kind of irony.

    --

    The enemies of Democracy are
  10. Re:overblown as usual by FrootLoops · · Score: 4, Insightful

    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.