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World's Biggest Dinosaur Constructed
Corey Sweeney writes: "The world's largest dinosaur skeleton, a seismosaur, was constructed in Bynum, Mont. this week. It's over 135 feet long and 22 feet high, and some have estimated that the seismosaurous could have weighed up to 150 tons. Disputes over how the seismosaur could have supported its own ponderous weight is the source of "interesting" theories of dinosaur evolution. "
*ducks back into the trench for cover*
Whoever wrote that page about dinosaurs and gravity obviosuly never saw the Horizon program (BBC Science program, can't remember what it's called in the US, maybe "Nova") on the "Natural History of an Alien".
They made a very interesting point about worlds with stronger gravity than earth. As gravity increases, so does air density and it increases in such a way that in a higher gravity environment the increase in air density is enough to allow even bigger flying creatures despite the stronger gravity.
For flying creatures, lifting force will increase as the square of the force of gravity.
So his point about bigger flying creatures needing weaker gravity is in error.
Bigger flying creatures implies stronger gravity, which kinda messes up his argument.
(If you didn't read the page, he's arguing that the existence of enormous dinosaurs implies that gravity was a weaker force in pre-history)
I tried, I really, really tried. I gave an honest College try, and attempted to work my way through the 'Interesting Theories' link.
What a bunch of BULL.
Remember the 'Religious Right' pages that sprouted all over the net like mushrooms after a rainstorm, as soon as South Park - Bigger, Longer and Uncut came out? That's exactly how the 'IT' article reads.
It's peppered with references to books published by Harvard Press, Oxford Press and whatever else - in an effort to add credibility to something that holds water like a sieve.
It's chock full of numbers that in another context might make sense, but here come out of nowhere to fit into an argument, and disappear again when they become 'inconvenient'. We all know how a liberal sprinkling of math tends to intimidate people into agreeing with the (obviously more intelligent) author. Microsoft does this a whole lot - as do tele-evangelists in their counting of statistical distribution of Deadly Sins in SP:BL&U
The ideas presented in the article are preposterous. They are a lame, ignorant attempt to answer some valid questions - but they are absolute 'sound and fury, signifying nothing'.
Read the article for amusement only. It's the pseudo-intellectual equivalent of FUD, and a great way to get the imagination of junior-high kids fired up. Nothing more.
-- What you do today will cost you a day of your life.
Interesting link referenced in this story. It links to none other than the web site of a well known creationist kook of talk.origins named Ted Holden.
The theory in his site is that dinosaurs must have experienced a reduced gravity (with respect to the present value) to be able support the massive weight of the larger species.
To support his argument he compares a very strong powerlifter to dinosaurs using the square cubed assumption for scaling (force produced by muscles goes up as a square of body length because it depends on cross section while weight goes up as the cube because it depends on volume).
Of course, the problem with all of this is that this scaling is way too simplistic since we are comparing apples to oranges (Homo sapiens to various sauropods, to be exact). Proof of this is that, contrary to Holden's claims, it doesn't even work for elephants.
From Holden's example, Kazmaier, weighing in at 340 lb., can do a 1000 lb. squat (not the strongest adjusting for body weight, see here, for an example). To see how this scales to a normal weight male (I shall consider myself at 175 lb. the norm for the sake of argument) we take the ratio my weight to Kazmaier's of 175/340 = 0.51. Taking the square cubed assumption it turns into .51^^(2/3) = .64 . meaning a normal 175 lb. person being able to lift .64 * 1340 lb. = 861 lb. to match Kazmaier's performance. As this figure includes body weight it turns into the ability to squat 861 lb.- 175 lb. = 686 lb.
Now, the most I've squatted is 450 lb. (which turns into 450 lb. + 175 lb. = 625 lb.) and I consider myself to have (for a nearly untrained person) near freakish lower body strength. I can assure any and all that I cannot move around comfortably with 450 lb. on my shoulders and can barely take some faltering steps in this situation (and, though I don't know the rules of powerlifting, I'pretty sure that the lift would not have been good enough to count in a competition --not that anyone would be likely to be impressed anyway).
Let's see what the most is that one can weight if the best lifting they can do would match my performance (better to compare myself --freakish lower body strength and all-- rather than a real athlete pushing the limits).
Using Holden's formula (which is correct, though its assumptions are flawed), we get:
The left side turns into 20.0 and the right turns into X^^(1/3). Cubing both sides we get that X = 8000. Thus, 8000 lb. is the most one could weigh to be able to carry one's own weight to match my lifting performance. Note that this doesn't mean walking around all day and even occasionally running quite fast (as elephants are known to do normally in the wild) but rather lifting one's own body weight badly with a maximal effort (and then, perhaps, sinking back exhausted into the couch to watch the Oprah Winfrey show).Adult elephants, on the other hand, can weight a lot more than 8000 lb.. And to those who may point out that my own bipedalism puts me at a disadvantage, I shall point out that circus elephants seem to be able to get on their back feet with great ease (it certainly seems to take a lot less effort than it takes for me to squat a mere 450 lb.)
Thus, taking a more reasonable lift for the scaling exercise and following Holden's assumptions, not only should elephant's fail carrying around their own weight, but they should fail miserably.
But elephants, even very large ones, seem to manage quite well, thank you very much. Thus, my claim that Holden's assumptions do not really hold up under scrutiny is supported
I definitely think it's worth a look, and it's a pity that by giving this article a score of 0 some people will miss out on reading these arguments.