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New Analysis Shows Dinosaurs Not As Heavy As Previously Believed.
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."
Dinosaurs. Not heavy, just big boned.
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.
pounds? for a minute there I thought we were talking sience...
Let's make the African elephant unit a standard.
This write-up gives reasons for doubting that the new technique does show dinosaurs were significantly lighter than previously thought.
"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
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...
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.
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.
Donte Alistair Anderson Roberts - hi son!
Karma: Chameleon
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
For me, it is far better to grasp the Universe as it really is than to persist in delusion
Was it a european or an african brachiosaur ? Do you think it could carry coconuts ?
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.
Wouldn't the buoyancy reduce their weight even more? Really, is there any reason they can't?
And I presume they'd outgas the excess hydrogen as burps which their gizzards (full of flint and iron ore) would ignite?
It's good to know that someone thought the same and followed through with it.
How do you know that's what they thought? Sure there's been a trend of weight decreasing from early estimates, but maybe they thought it would confirm the latest estimates, or even show them to be heavier. Maybe they just thought that they had a novel new method of estimating the weight and should see what it says.
Which, regardless of their expectation of the result, was what happened. That's the key, going where the results suggest, not where you expected.
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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?
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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.
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What's so wrong with a changing belief anyway? Why this fixation on having an unchanging and un-adaptable view of the world?
I've changed a lot since I was born. My home town has too (though not as much some other places!). Very little in nature stays the same over a lifetime; rivers get different flow paths; lizards stop laying eggs and go placental. How I knew the world to work when I was seven is very different to how I knew the world to work at age 21 or how I know the world works at age 35. Things I knew to be true in the past turn out to be wrong or incomplete, and no doubt some of the things I hold to be absolute in my life now will turn out to be less than that in the future.
So why is it so bloody bad that theories and scientific understandings of the world change over time? Why do those choose to believe in system they profess hasn't changed in 2000 years (even though it clearly has changed and is still changing) get to be all "AHH! I CAUGHT YOU!" every time science discovers something that changes our view of the world? All modern science is built on the idea of falsifying the results of others, so off course some things are going to be found to be not true. All good scientists should be able to say "of course, I could be wrong - and this is how". AND THIS IS A GOOD THING.
I don't see many religious people willing to say that same thing... and I would guess that's why they feel it is so incompatible with their world view.
A view of the world that claims to be unchanging and immovable is clearly lying, and is clearly a faulty and unnatural way to be. It is for that reason that it should be expunged from the system.
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 artists for it. They rendered the soft tissues of the models as specified by the scientists.
It took years before there was a better understanding of dinosaur anatomy. Take a look at reconstructions from the 1960s or 1970s versus more recent ones, and that explains most of the change. These "lighter dinosaur" models have been showing up in the last 10 years or so as 3D computer modeling techniques have improved (that 80 tonnes estimate is decades old), so this change isn't really news either. A few papers were already challenging the old numbers a few years ago. And if you fault the older estimates, well, you have to start with something. It's the normal process of refinement in science as techniques improve.
I do not think that Science is like Religion. Like I said, this article is a Good Thing.
You made it sound like this is the exception to the rule ("I'm glad that some..."), rather than the rule itself.
However, you can't deny that scientists are imperfect and sometimes act that way.
The scientific method is premised on the idea that scientists are imperfect.
In order to overcome growing public growing, rationalists must be like Avis and "Try Harder" at being humble and not so dogmatic.
I'm not sure that's so. Look, you point at this article saying "Is it any wonder people don't trust science?", then point out how science is always changing its mind. You said it's Dogmatic when as a rule it isn't, but then again the people you're talking about don't have a problem with Dogma, do they? They just don't like it when it admits it was wrong and changes.
The unspoken implication, which I think is more correct, is that Joe Fundamentalist Six Pack would be more likely to believe in science if it was more dogmatic, and didn't change hypothesis in light of new data. "Don't worry folks, Brachiasurus weighs 80 metric tonnes and egg whites are bad for you, always and forever."
Which is why we should never, ever change how science is done to win over people whose fundamental issue is that they don't understand science, don't want to understand science, and thus can't be arsed to try.
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