From: swf@teradata.com (Stanley Friesen)
Newsgroups: talk.origins
Subject: Re: Holden "felt effect" followup
Date: 21 Jul 92 03:40:32 GMT
Reply-To: swf@tdat.teradata.com (Stanley Friesen)
Organization: NCR Teradata Database Business Unit

In article <711611294@sheol.UUCP> throopw@sheol.UUCP (Wayne Throop) writes:
|A lot of this, as Ted himself points out, is repetetive.  I wouldn't
|post it if Ted would acknowledge it and rebut it, but he doesn't,
|so I re-present it.

Repetitive is an understatement!  The Tedster has been saying almost exactly
the same thing (even using many of the same *sentences*) for as long as I
have been on the net, and that has been for some time.

|The observed diameters of bones go as m^(1/2.73), not m^(1/3) as Ted's
|calculation requires.  So, correcting for the additional cross section
|and leverage implied by this thickness ratio, we get this: ...
|
|Solving the above formula for Kazmaier's 350 lbs of mass and 1660 total
|load, then calculating the mass of the animal just able to stand with no
|additional load in 1G gravity, we get about 600,000 lbs of mass.  This
|is well beyond any of the largest dinosaur estimated masses.  (Note: Ted
|estimates masses for breviparopus as larger, but his estimate for
|breviparopus and seismosaur are both erronious due to his confusion over
|Diplodocids and Bracihosaurids.)

I should say so! The largest *serious* estimnates for the masses of these
dinosaurs have been about one third of the above figure (about 100 tons).
I have seen no paleontologist who seriously suggested a 300 ton weight
for *anything*.

|(Note also: earlier versions of this
|corrected formula I used corrected only for cross section, not for
|leverage...) (Note again also: I do NOT claim that this estimate is very
|accurate, only that it correctly accounts for some factors that Ted
|overlooks.  Somewhat more complicated corrections would be needed to get
|accurate results.)

Want to bet that the more accurate you get the larger the maximum gets?
[Hmm, thought not].

|As usual, Ted ignores the fact that 200+ lb human-plus-hang-gliders
|fly quite regularly. 

Hmm, *nice* point.  In fact I believe that even large, heavier gliders
are launched quite regularly.  (Ted, can you say 'lift ratio'?)
(Not to mention the Gossamer Pteranodon - a life size, actually flying,
replica of a real Pteranodon, and the replica certainly had less
effective dynamic controls than a living animal)

|In brief, Ted's supposition that a lesser
|effective acceleration (which seems to be what Ted means by his "felt
|effect" of gravity) is the only way for the largest teratorns and
|pterosaurs to fly (creatures which *may* have been up to 350 lbs in
|weight (but might also been as little as 90 lbs, see the Alexander
|reference above for details), is clearly incorrect.

I *really* doubt a 350 lb. weight for the larger pterosaurs.  Those
beasties had *really* *thin* bones, like paper.  It would take *lots*
of muscle and guts to build one of them up to such a massive weight
as 350 lb.

|>    A tyrannosaur was basically a big carniverous kangaroo.  A look at its
|> body should make its lifestyle clear enough;  it lived by bounding after
|> prey on two legs, kangaroo style, then clomping those big teeth around a
|> victim's throat, and then hanging on until the victim died.  This
|> necessarily involved some tumbling.
|
|No comment.  You may hear strangled laughter, but no comment.

Gack, sputter, choke!

A Tyrannosaurus *bounding*, like a *kangaroo*!?!?!?
The last person to suggest this was Dr. Cope, when he discovered Laelaps.
The leg anatomy (for those of you who have not already figured this out)
of a Tyrannosaurus was essentially similar to that of the *ostrich*, a
fast *runner*.   Also, the teeth of T. rex were ill suited to *grasping*,
they were designed for *tearing*, and *slicing*, sort of like a great big
cookie cutter.  (If T. rex held anything, it was with its *front* *limbs*,
which were the massively strong).

But then, T. rex probably *did* do *some* rough and tumble in bringing
down prey, just not this silly sort.

-- 
sarima@teradata.com			(formerly tdatirv!sarima)
  or
Stanley.Friesen@ElSegundoCA.ncr.com
Newsgroups: talk.origins