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- Path: sparky!uunet!news.tek.com!tekig7!tekig6!alanf
- From: alanf@tekig6.PEN.TEK.COM (Alan M Feuerbacher)
- Newsgroups: talk.origins
- Subject: Re: Muscle tissue from mouse to sauropod
- Message-ID: <8507@tekig7.PEN.TEK.COM>
- Date: 28 Jan 93 21:04:35 GMT
- References: <243@fedfil.UUCP^<8411@tekig7.PEN.TEK.COM> <246@fedfil.UUCP>
- Sender: news@tekig7.PEN.TEK.COM
- Organization: Tektronix, Inc., Beaverton, OR.
- Lines: 217
-
- In article <246@fedfil.UUCP> news@fedfil.UUCP (news) writes:
- >In article <8411@tekig7.PEN.TEK.COM>, alanf@tekig6.PEN.TEK.COM
- >(Alan M Feuerbacher) writes:
- > .....
- >You've missed the entire point. The point is, that Kazmaier is so much stronger
- >than any kind of animal his own weight, that in any given situation in which
- >he would be unable to stand due to gravity, neither would any other animal,
- >and certainly neither would any animal, the bulk of whose weight was devoted
- >not to muscle or anything useful in lifting, but to the huge digestive system
- >needed to handle leaves and other low-value foods. That includes sauropod
- >sauropods.
-
- I think you're deliberately ignoring my point. You've not proved or
- even given evidence for anything remotely like what you claim.
-
- I'll allow that you've shown a 20,000 pound Kaz would just barely be
- able to stand. I'll admit that sauropods probably could not squat
- 200,000 lbs or bench press their own weight. But you've not given
- any evidence that shows sauropods can be directly compared to Kaz,
- or that a number of other factors may be ignored in such comparisons.
-
- My point was that, since it is observed that different physiologies
- do in fact exist, you are unjustified in merely *claiming* that Kaz's
- physiology can be compared to a sauropod's.
-
- I'm not arguing anything about _Archaeopteryx_. I posted the article
- only to point out some of the experimental evidence you insist on
- ignoring.
-
- _Parade_ magazine did an article a few years ago about a man in New
- York who reached about 1600 lbs and was in serious trouble because
- he couldn't walk after he reached about 1200 lbs, if I remember right.
- The only exercise he ever got was stuffing food in his face. This
- proves that a man very near the 1350 lb limit you use for Kaz can
- indeed walk, without having done any extra exercise or taken any
- strength enhancing drugs, as you say Kaz did. Had this 1200 lb man
- done the kinds of exercise Kaz did, can you put a limit on how heavy
- he could have gotten? Even though most of his bulk was fat tissue, he
- was able to walk until he reached 1200 lbs, even though his normal
- weight might have been 150-200 lbs.
-
- In a chapter on dinosaur locomotion, Robert Bakker, in _The Dinosaur
- Heresies_, shows a side by side comparison of the skeletons of a
- 5 ton African elephant and a 5 ton ceratopsian. The leg bones of
- the ceratopsian are *much* thicker than the elephant's. This
- simply shows that animals of equivalent weight can be built
- quite differently -- one relatively lightly and the other much more
- robustly. Therefore, using the elephant as confirmation of your
- scaling factor without allowing for the possibility of different
- physiologies is again shown by observation to be incorrect.
-
- > .....
- >The analogy with reptiles is meaningless in the case of the sauropods for
- >reasons mentioned, and it is also meaningless in the particular case
- >of the Argentinian teratorn, a 160 - 200 lb modern eagle. As I've noted,
- >central asians have been attempting to breed eagles for size and strength for
- >all of recorded history, and they cannot get them past 25 lbs (the berkut).
- >Beyond that, they cannot take off or land well enough to be functional, and
- >this is fully documented in the book which I have mentioned (BIRD OF JOVE).
-
- All this says is that eagles can't get very big. You can't breed for
- a 20 lb tomato but does this prove that squash can't reach 700 lbs?
- What if squash were extinct? Would that change anything?
-
- > .....
- >^Ruben stated that _Archaeopteryx'_ skeletal structure indicated that
- >^it supported a relatively small mass of wing muscles, compared to
- >^modern birds, and that because various other features indicate it
- >^was certainly capable of flight, something was missing.
- >
- >In other words, the evidence is all there that the creature flew, but
- >the musculature for something its size to fly appears to have been
- >missing. There is one possibility which somebody here is not even
- >considering, isn't there? That is the possibility that felt gravity was
- >then heavily attenuated as I have mentioned, and what would be the
- >required musculature in our world would not be needed.
-
- The musculature for flying was *not* missing, it just appears to be
- poor. _Archaeopteryx'_ physiology and flying ability have been
- compared to the South American hoatzin, which is a very poor flyer.
- The hoatzin has a large crop that leaves little room for flying
- muscles. Yet it still flies. By your reasoning the hoatzin's
- existence ought to prove that gravity is not as strong as we
- think it is.
-
- >.....
- >Again, this doesn't help at all for the 200 lb teratorn. You require a
- >general solution here; I have provided one, Ruben has not.
-
- Young earth creationists have also "provided" a general solution.
- Many of them claim that some sort of vapor canopy surrounded the
- earth before Noah's Flood, and atmospheric pressure was maybe twice
- what it is now. This increased air density explains why pterosaurs
- and giant birds could fly, or so they claim. Why is your general
- explanation any better than theirs? Why is either expanation better
- than just accepting that _Archaeopteryx_ was a poor flier?
-
- >......
- >^ This is related to a previously unrecognized attribute of
- >^ reptilian muscle physiology: During "burst-level" activity,
- >^ major locomotory muscles of a number of active terrestrial
- >^ squamate reptiles generate at least twice the power (watts
- >^ kg^-1 muscle tissue) as that of birds and mammals. Furthermore,
- >^ patterns of metabolic power output during intense exercise in
- >^ crocodiles... suggest high-power locomotory muscle tissue occurs
- >^ in a broad range of diapsid reptiles.
- >
- >At least three problems here:
- >
- >1. It contradicts the Nielson article, and I have no apriori reason to
- > prefer Ruben here.
-
- I'm not qualified to compare Nielson's and Ruben's work. Anybody
- else want to try?
-
- >2. It doesn't help the Argentinian teratorn, as noted. Some altogether
- > different (and no doubt, equally fanciful) explaination will be required
- > for the teratorn.
-
- Think about tomatoes, squash and hang gliders.
-
- >3. There is no reason to believe that it would help the sauropod even if
- > applicable, which is doubtful. Twice the force (which you're probably
- > still not even talking about) still will not help the ultrasaur, which
- > would require being MORE than twice as strong as a scaled version of
- > Kazmaier its own size just to stand for three seconds, much less move
- > around all day long, as it actually had to.
-
- Again, the problem is not for me to prove that sauropods had mammalian
- or reptilian style muscles, or even something else, but for you to
- show why the possibility of very different physiologies can be ignored
- in your scaling argument.
-
- >.....
- >^ Enhanced reptilian muscle power is probably due to a variety of
- >^ factors, including elevated intramuscular contractile fiber
- >^ concentration of mitochondria-poor reptile muscle, and
- >^ particularly, high contractile velocity facilitated by
- >^ accelerated ATP turnover and high specific activities of
- >^ myosin-ATPase and rate-limiting ATP-forming glycolytic
- >^ enzymes.... Accordingly, even though lizards and mammals attain
- >^ similar sprint speeds..., skeletal muscle mass in reptiles is
- >^ less than in equivalent-size mammals (reptilian skeletal muscle
- >^ mass, in grams, scales according to the equation
- >^ 0.19 [grams total body mass^1.09]; for mammals, the equation is
- >^ 0.42 [grams total body mass^1.01].
- >
- >Correct me if I'm wrong: I should think that the Nielson article would
- >still hold true in terms of the max FORCE which a muscle could exert
- >(which is the applicable nexus in the case of sauropods), particularly
- >when you consider the time spans which were likely involved in any
- >sauropod motion. I don't see burst activity as particularly applicable.
-
- I'm not qualified to comment. Anyone else?
-
- >^ Utilization of high-power, reptile-type flight-muscle to support
- >^ powered flight seems consistent with _Archaeopteryx'_ relatively
- >^ reduced pectoral surface area....
- >
- >Again, the notion of attenuated felt gravity is an equally good candidate
- >for an explaination and also works for the teratorn. Reptilian flight
- >muscle does not work for the teratorn.
-
- The vapor canopy theory is just as good. :-)
-
- >^ [Various] observations are
- >^ strongly indicative that _Archaeopteryx'_ capacity for
- >^ generation of flight-muscle power was at least equal to that of
- >^ many living birds.
- >
- >The same old dilemma... the thing flew (obvious from physiology), and yet
- >could not have flown given musculature and what we know about flying creatures.
-
- Sure it could have flown with a standard bird physiology -- just
- not terribly well. Many of Ruben's conclusions have been disputed.
-
- >There's one final little problem which I should mention which Ruben does not
- >even address, and which your "reptilian muscle" thesis certainly falls flat
- >on.
- >
- >Adrien Desmond (HOT BLOODED DINOSAURS) that thorough calculations indicate
- >that fifty lbs or thereabouts is the absolute maximum size for any flying
- >creature in our world, and that beyond that, even simply holding wings in
- >a turn, much less flapping them, would break bones.
-
- I'm reminded of the story (I don't know if it's true) that 19th
- century scientists calculated that powered flight was impossible.
- Wasn't there a thread on this awhile back? Whether the story is
- true or not, I don't think anyone knows enough about physiology
- to calculate limits such as this.
-
- >This corresponds quite well with what we actually observe. The largest
- >flying creature which does much in the way of flapping (relatively much
- >for a creature the size) is the berkut, the largest specimens, such as
- >Atlanta, go around 24 lbs. The largest soaring creatures which we actually
- >find, albatrosses, condors etc., go around 30 or 35 lbs.
-
- Again, all this means is that they don't exist *today*. You need a
- lot more evidence to claim they were physically impossible under
- today's conditions.
-
- >All in all, this is the best attempt I have seen on t.o to refute my basic
- >thesis, and certainly requires an answer. And, given time, I've no
- >particular problem replying to this sort of article.
- >
- >I shall be out of town for the next week, so try to time any follow-ups
- >to arrive around 1/30.
-
- While you're at it, could you please explain to me how the law of
- conservation of angular momentum is not violated by the hypothesis
- the earth once orbited an "electromagnetic star" with one pole
- forever pointed toward the star? If I understand anything about
- physics, it's that conservation of angular momentum is fundamental.
-
- Alan Feuerbacher
- alanf@atlas.pen.tek.com
-
-