Posted on 03/21/2008 2:01:20 AM PDT by Swordmaker
When did you provide ANY links to anything. I provided you a link to an article published in the Proceedings of the National Academy of Science which has all of that information in it. You ignored it. I'm not going to link to it again.
And please don’t feed me the shit that Ted Holden’s physics is compatible with anything actual scientists do. You may thin the Electric Universe stuff is cool, but I rather doubt that either you or Ted are smarter than working physicists.
More ad hominem...
Now, about those "idealized spheres" and the Square Cube Law only applying to them... Source? Link? Authority?
What do you think is an acceptable weight for a 110 foot sauropod? Answer the question.
Apparently it is real easy to throw spit wads like you continually are doing, but it is hard for you to answer ANY questions.
PUT UP or SHUT UP.
There you go, attacking a mathematical LAW again... it works, so long as the compared specimens are proportionate... unlike your mis-applied use of the law to unlike birds.
Source? Authority? Link? PROOF!
why is the wing loading of the teratorn exactly in the middle range of modern birds?
Put MUSCLES on that wing and move it... with a 170 lb body hanging from it.
The Square Cube Law IS a law of Physics... how can you defend ignoring it?
As pointed out on here... and these six times larger dragonflies have NO adaptation for their larger size... no proportionately larger wings, which are only 36 times larger surface area to support the dragonfly's 216 times heavier weight, no larger muscle attachment points on their exoskeletons to support the larger muscle engines needed to lift the dragonfly with its far heavier weight ... this flies in the face of logic.
Something was different about conditions that allowed dragonflies of this size to live and fly. What?
Excuse me, but the weights associated with these few bone fragments were PREPARED and PUBLISHED by the expert paleontologists. I am merely looking at the implications such weights bring up.
So which expert paleontologists are you quoting that disagree with the published weights, lengths, etc.? Links? Authority? PROOF? Please, please, please, provide some.
You continually make assertions without providing anything except YOUR unsupported word. That's makes it BS.
Yes, that is the question. My thought was as follows: Since insects are limited in size by their respiratory system, not their weight, and these six times larger insects have NO [structural] adaptation for their larger size, whatever was different about their environmental conditions had to increase the efficiency of their respiration.
As far as the food issue goes, we’re talking lizards here, not warm blooded animals.
An alligator might be a bit hungry but can survive on one good meal in a year, IIRC.
Higher oxygen percentage.
Wing loading is simply weight divided by surface area of the wing. My question remains, has average or typical wing loading changed since the time of your teratorn, and if not, why not?
Ted's ramblings have been answered by real scientists. A quick overview can be found here.
Re: lizards and cold blood.
Nope. The latest scientific evidence is that the Dinosaurs were much more closely related to birds and may even have been feathered. As such they were most likely warm blooded.
If you can demonstrate to me the existence of even one single type of warm blooded lizard, then your hypothesis might be valid.
Until then, it is just a hypothesis. Comparisons with birds or mice or cockroaches nonwithstanding. And the known facts point towards dinosaurs being cold blooded.
The estimated wing loading of the Argentavis magnificens is 11.5 Kg/M2. That Wing Load figure is consistent with modern birds that fly by continued flapping of their wings... a mode of flight that is not used by large raptors.
It is not consistent with the similar proportioned California Condors. The Wing loading of the Gymnogyps californian is only 7.21Kg/M2 of wing area... and they have trouble getting off the ground.
The slightly smaller Albatross, a gliding rather than a soaring bird (has a narrower wing), has a wing loading of 9Kg/M2. It has even more problems with getting off the ground and landing... that's why they earned the name "Gooney Bird."
Using your 11.5 Kg/M2 figure, the Teratorn's wing loading is almost 60% greater than wing load of the largest soaring birds today. Using formula developed by Theodore von Kármán for determining the wing loading of soaring birds, it's 19 Kg/M2 - 167%. I think that's a bit extreme... and might be because "Soaring Birds" include smaller birds such as song birds. I suspect the actual wing load figure is probably closer to the 11.5 Kg/M than to the von Kármán's. In addition, working backwards using von Kármán's formula from the calculated wing load, you find it fits a wing of only 4M2 rather than the known 6.7M2 wing area of the A. Magnificens.
If the Teratorn were adapted to modern 1G conditions, either the wing size should be ~50% larger in area or the bird needs to weigh 33% less to bring it into the range of similar soaring birds today... around 7 to 8 Kg/M2... rather than the 11.5Kg/M2 that it is.
Which brings us back to the basic problem... we KNOW the mass and we know the wing size and they don't fit.
There is some evidence for that... I've seen a figure for O2 of 18 - 24% of the atmosphere.
Nice pictures of static suspension bridges supported by steel cables... irrelevant to the discussion. A cantilevered bridge would be more apropos but even there the structure of the sauropod neck is not very close to a cantilever bridge.
I especially liked this comment by the "real scientist" at your link:
I made some experiments to find out whether the idea was feasible. [...] the mass of the real head and neck would have been 1,340*10 = 13,400 newtons. [...]
First of all, he did no "experiments;" he did some calculations. Secondly, a Newton is a unit of force over distance and time not mass... it acts on a mass. A Newton is the force neccesary to accelerate a 1 Kg mass to 1 meter per second2. Perhaps the real meaning got lost in the ellipses? Did it originally say "The force necesssary to support ..."? That I can agree with.
More from your link:
Even considering the seismosaur, which very much resembles a 1.6 times scaled up diplodocus, and therefore (if isometrically scaled) would have had 1.6 times the load per area in its nuchal ligament,
This seems to be nonsense to me... how does isometrically scaling up the beast by 1.6 times increase the load per area of its nuchal ligament by only 1.6 times??? The mass at the other end of the nuchal ligament is 4.1 times greater... while the ligament is only 2.56 greater in area. There is a factual disconnect here. I have a serious problem with the claim that the Seismosaurus at 1.6 times larger than Diplodocus with essentially similar neck structure will have only 1.6 times more stress on its neck. This is ignoring, again, the Square Cube Law and assuming that scaling of mass is linear. It isn't. Any engineer can tell you that.
Let's go over it again... the cross section of the neck muscles and ligaments, and therefore the strength of the neck muscles and ligaments, increases by the SQUARE of the multiplier... 1.62 or 2.56... while the MASS or WEIGHT of the neck increases by the CUBE of the multiplier... 1.63 or 4.1. The strength of the Seismosaurus' neck would be 2.56 times stronger than the neck of the Diplodocus, but that increase strength would have to support and lift and move a mass that is 4.1 times as heavy.
Let's see what the real scientist does with this his data for the Diplodocus...
...the weight acts 2.2 meters from the joint and the the ligament tension have been needed to balance the weight is 2.2 * 13,400/0.42 = 70,000 newtons (7 tons force). The third force shown in the diagram [seen here] is the force in the joint itself, where one centrum presses on the next.The calculated tension may seem enormous, but the ligament was very thick. If it was as thick as in the diagram, its cross sectional area was 40,000 square millimeters and the stress in it, for a force of 70,000 newtons, would be 1.8 newtons per square millimeter. This is more than the stress in the ligamentum nuchae of a deer with its head down (about 0.6 newtons per square millimeter), and would be enough, or nearly enough, to break ligamentum nuchae.
All that was calculated for the Diplodocus... Why didn't he do it for the Seismosaur??? He just made some ex cathedra assertions about how everything is OK with Seismasaurs and even bigger beasties... without proving it. Since he didn't, let's do it for him, and scale up the data to represent the Seismosaurus...
2.2 meters from the joint becomes 1.6 x 2.2 m = ~3.5 meters from the joint.
Taking his low-ball 1,340 Kg mass for the Diplodocus head and neck (heck, he might be right...) then the 1.6x scaled Seismosaurus' neck and head would weigh in at 5,494 Kg. It would take 54,940 Newtons of force just to support that larger neck and head against a 1G (10M/s2) gravity field. Let's plug that data into the calculation for the force on the nuchal ligament: 3.5 * 54,900N/0.42 = 457,500 Newtons! That's six and a half TIMES more force to support the neck and head with the nuchal ligament that worked OK for the Diplodocus!
The Diplodocus' 40,000 mm2 nuchal ligament is also scaled upward by 1.62 or 2.56. Is it enough to keep the Seismosaurus' head off the ground? Let's see.
40,000 mm2 * 2.56 = 102,400 mm2. If we now divide the force into the area of the Seismosaurus' scaled up ligament, we find that the 1.6 Newton per square millimeter of the diplodocus' nuchal ligament, which was "enough, or nearly enough" to break it, is now almost 4.5 Newtons per square millimeter... well beyond the force needed to break the Seismosaurus' Nuchal Ligament!
I wonder if that is the reason he didn't do the calculations on the Seismosaurus?
That's begging the question... taking as a given the false premise that Dinosaurs are reptiles.
While not a "lizard," this reptile, the Leatherback Turtle, is indeed a warm-blooded reptile:
"The largest of all living reptiles, the leatherback, Dermochelys coriacea, is an annual visitor and rare nester on the southeastern coast of United States. April and early May seem to be the period of the leatherback migration into Georgia waters. This concentration of turtles coincides with the occurrence of vast numbers of the cannonball jellyfish. The diet of these huge turtles is made up almost entirely of jellyfish.Interestingly, the body temperature of this reptile is warmer than its surroundings. This makes the leatherback the only known "warm blooded" reptile. - Gray's Reef National Marine Sanctuary
Apparently your "known facts" are a bit outdated?
Please read the science that has been developed about dinosaurs over the last 30 years and pay particular attention to the growing fossil samples with feathers... then get back to me on the idea that Dinosaurs are lizards.
The wing loading of your teratorn is well within the range that allows flight. Flapping to take off is certainly the dominant method used by birds, but it is not actually necessary.
Your claims for the necessity of believing gravity has change require proof that flight is impossible, not simply that we can’t answer detailed questions about the behavior of an extinct species.
I’m going to ask again: there are many extinct bird species; do you have any evidence that average or typical wing loading has changed since the age of the dinosaurs? Have you even bothered to consider the question? If not, why not?
That's pretty much true of this whole argument. There are some animatronic dinosaurs that make the rounds of museums. I'd like to see some full scale animatronic sauropods. Making them support themselves and move would require solving the actual engineering problems.
Somewhat less expensive would be a working mock-up of the necks.
These efforts sometimes bring surprising answers. There is a guy building a life-size mock-up of Stonehenge, single-handed, using only his own muscle power. Inventiveness is often more powerful than assumption.
There has been some suggestion that these giant plant eaters were aquatic. In that case, the water would have supported much of the weight.
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