ted@imsvax.UUCP (Ted Holden) (08/19/85)
Before anyone corrects me on either of these points, let me
say that I've seen "pteratorn" spelled with and without the 'p',
and estimates of weight for same between 150 and 250 lbs. Not
that the later point matters; a 150 lb bird couldn't fly any more
than a 250 lb bird. At least, not NOW.
David Canzi writes:
>I'll give Ted the benefit of the doubt, and assume for the sake of
>argument, that the pteratorn existed, would not be able to fly today,
>and that the force of gravity was weaker before the flood. If all this
>is so, then, even in lower gravity, the pteratorn would *still* not be
>able to fly.
>
>Sure, the bird would weigh less, but so would the air. The lighter air
>would, as a result have lower pressure, and as a direct result lower
>density. Even though the bird would be lighter, the thinner air still
>wouldn't be able to support it.
The air was thick enough to breathe, or we wouldn't be
here. It could be that birds just flew a little faster just like
planes fly faster at 20000 ft. than at 10000 ft. to get the same
lift from their wings. I hate to say this. Contrary to what my
boss likes to tell our customers, I don't really know everything,
YET. I'm still working on it. I don't know what effect, if any,
lighter air might have had on inhabitants of the archaic world,
including the pteratorn. We later day catastrophists have put
bits and pieces of the picture together until we can see a little
bit of the archaic world. The best I can do is to tell you what
I do know:
1. A 200 lb. bird could not possibly fly in our world, for
reasons having to do with power to weight ratios. Don't
take my word for this. You reside in a major university
with physics and engineering departments. Have them do the
calculations.
1.1 Consider that the largest birds which fly now, thirty
pounders which can barely take off and land, are, with the
single exception of the Berkut eagle, bird equivalants of
gliders and cargo planes i.e. their wings are made for lift
and soaring. The pteratorn was a bird equivalant of an F16,
his wings being made for aerial maneuver, swooping, and
pouncing. How much more impossible his life! The biggest
Berkuts, by the way, vary their weight from 22 to 26 lbs or
so; at 22 lbs, they fly and kill things, at 26 lbs they sit
around feeling fat and happy and wait until they get back
down to 22 or so to fly some more.
2. The pteratorn flew in the archaic world. Birds which don't
fly, including penguins, ostriches, the now extinct moas
etc. are adapted for running, swimming, or some kind of
scheme in which they earn their living by means other than
flight. Their wings are very obviously useless for flight.
A pteratorn was a scaled-up golden eagle. Without being
able to fly, he would present no danger to his natural prey
animals other than the possibility that they might die
laughing. Picture a penguin, knife in hand, chasing one of
the big jack-rabbits found around Austin or San Marcos and
you've just about got it. Without being able to capture
these prey animals, the pteratorn would quickly starve.
McDonalds was not an option for him.
3. Brontasaurs and Ultrasaurs, in all likelihood, could not
even walk in our world. Every book on dinosaurs I have ever
read in which the author did any thinking, makes some
mention of this problem. Most claim that the brontosaur
lived in water, since his legs would not easily support his
great bulk on land. But the brontasaur, if water based,
would have needed huge flat feet to keep from sinking
hopelessly in the mud on river bottoms and floundering. He
didn't have them.
4. The ultrasaur is a relatively new find. Much larger than
the brontasaur, he will not likely appear in standard
dinosaur books. In an article on the Wash. D.C. area's WETA
public TV network, channel 26, the narrator claimed a 20
foot span from this creatures backbone to his belly. He
said: "If this guy swallowed you and you set up housekeeping
in his stomach, you'd need a hell of a ladder just to
change a lightbulb". Weight would be a far worse problem
for the ultrasaur than the brontasuar. I like to use the
case of the pteratorn in my "gravity" spiel because it's
easier for most people to comprehend. The case of
brontasaurs and ultrasaurs is an equally valid argument for
lesser gravity in the archaic world; it simply requires a
little more thought.
5. The only logical explanation for these impossible animals is
that the felt effect of the force of gravity was less in the
archaic world than it is now. Rather than attempt any more
brief explanations of the nature of the archaic world and
have 50 more people call me a pseudo-scientist, I hereby
recommend that you purchase a copy of David Talbott's book
"The Saturn Myth", 1980, under the DoubleDay label. It is
the only intelligent book on the nature of the archaic world
which I am presently aware of.
6. Consider the one place on this earth where really big
animals are found today, namely the oceans. There also, due
to the effect of water bouyancy, the felt effect of gravity
is less than what we experience. Funny coincidence, isn't
it.
7. Aside from sizes, there is another thing which decreased
gravity might correllate with. Gravity is the major source
of all stress on land animals. Creatures living with less
gravity than we live with might live longer than we do. Of
course, other things, such as parasites and disease effect
lifespan too. But it is known that several species of
Chinese carp and goldfish regularly live more than 200
years, and scientists are unsure how long big sharks and
whales live. Possibly very long, at least in some cases.
8. Genesis claims that the lifespans of the men between the
generation of Noah and that of Abraham were shortened
something like 100 years per generation. This same notion
appears elsewhere in Jewish Midrashim. Louis Ginzbergs
"Legends of the Jews", vol I, page 172 contains the note:
"The brother of Peleg was called Joktan, because the
duration of the life of man was shortened in his
time."
The notion of longer lifespans in the archaic world is
common in all mythologies. In Hesiod's "Works and Days",
(back to Greek mythology for the moment), there is a
reference to an ancient fear that there would be an age
"when babes would be born with grey beards". Apparantly, at
one time, humans were losing time that fast.
9. The archaic world was radically different from our world.
There is no telling what a "year" meant to the authors of
Genesis. But consider ratios. Our ratio of the age of
physical maturity for men to the lifespan of men is
something like four or five to one. For the antediluvians
whose generations are recounted in Genesis, this ratio is
more nearly 13 or 14 to one. mrh@cybvax0.UUCP (Mike Huybensz) (08/20/85)
Without checking articles on Pteratorns, there are still a great number of reasons for rejecting the low-gravity hypothesis. First, the physical limits referred to for mass of flying birds were calculated for SUSTAINED POWERED FLIGHT. As human glider and hang-glider pilots can tell you, they don't say much about limits of unpowered flight using thermals and updrafts (which, by the way, is how most large predatory birds sustain their extended flight.) Second, if lower gravity had existed, it would have had MANY more effects than just two or three unusually large animals. Sedimentation, waves, vegetation, and a host of other fossil evidence would have been quite different. Instead, we find fossilized trees with normal amounts of support tissues, and no bigger than today's redwoods (which would probably also be cited as evidence of low gravity and lack of disease or aging if they were known only from fossils. :-) -- Mike Huybensz ...decvax!genrad!mit-eddie!cybvax0!mrh
friesen@psivax.UUCP (Stanley Friesen) (08/28/85)
In article <375@imsvax.UUCP> ted@imsvax.UUCP (Ted Holden) writes: > > 1. A 200 lb. bird could not possibly fly in our world, for > reasons having to do with power to weight ratios. Don't > take my word for this. You reside in a major university > with physics and engineering departments. Have them do the > calculations. > And when they do it is *you* who will be surprised. Yes power to weight ratios are important, but power problems can always be solved by building a larger power plant - i.e adding more muscle. I suspect that any "calculations" which say that the Pteratorn (Greek for Wingbird) coudln't fly were based on simple proportional scaling from the largest existing eagles. The correct procedure is to produce a allometric equation relating body size and muscle mass in eagles and extend it up to the size of the Pteratorn. The results are almost certain to be that it *could* fly. In fact the extra ~100 lbs in the higher weight estimate may be just such a correction! Remember the same physics controls airplane flight as bird flight, and we build perfectly good airplanes that weigh many *tons*, it is just a matter of supplying enough power. > 1.1 Consider ...the Pteratorn was a bird equivalant of an F16, > his wings being made for aerial maneuver, swooping, and > pouncing. How much more impossible his life! The biggest > Berkuts, by the way, vary their weight from 22 to 26 lbs or > so; at 22 lbs, they fly and kill things, at 26 lbs they sit > around feeling fat and happy and wait until they get back > down to 22 or so to fly some more. > A large part of the reason that a 26 lb berkut Eagle cannot fly is that the extra poundage *is* fat, not muscle. Its flight apparatus is powered for a weight of 22 lbs. This is like putting a trunk full of lead in a piper cub and expecting it to fly! Yet an airplane with a larger powerplant will easily lift a trunk of lead! In other words, the difficulty which the heaviest Berkuts have with flying is *irrelevant* to wether a Pteratorn could fly. > 3. Brontasaurs and Ultrasaurs, in all likelihood, could not > even walk in our world. Every book on dinosaurs I have ever > read in which the author did any thinking, makes some > mention of this problem. Most claim that the brontosaur > lived in water, since his legs would not easily support his > great bulk on land. But the brontasaur, if water based, > would have needed huge flat feet to keep from sinking > hopelessly in the mud on river bottoms and floundering. He > didn't have them. > Again, totally incorrect. The myth that these animals could not support themselves on land was *never* supported by valid calculations. It originated because the first fossils of this sort of dinosaur were thought to be the reptilian equivalent of whales(since no leg bones were found in the original find) - it was called Cetiosaurus, meaning Whale Lizard. Then the leading palaeontologists looked at these beast and said "I do not believe they could walk on land at that size" and everyone believed them - without checking it out. When we finally got around to actually performing the necessary calculations the results were that the skeletons of these animals were *completely* capable of supporting them on land, in fact they had the normal amount of safety margin for large land animals. Try reading some of Colbert's later books on dinosaurs, or look at some recent articles on the subject in journals. The latest weight calculation was, I believe, in a recent of the Linnaean Society Zoological Journal. > 4. The ultrasaur is a relatively new find. Much larger than > the brontasaur, he will not likely appear in standard > dinosaur books. >> A lot of Gee Whiz stuf of no real relevance deleted > Weight would be a far worse problem > for the ultrasaur than the brontasuar. There is no reason to suppose that the Ultrasaur(nor even the Supersaur - another new "brontosaur") would have had any less of a safety margin than any other Sauropod dinosaur. > > 5. The only logical explanation for these impossible animals is > that the felt effect of the force of gravity was less in the > archaic world than it is now. Actually, the only logical explanation is that you are hopelessly out of date with your facts. > > 6. Consider the one place on this earth where really big > animals are found today, namely the oceans. There also, due > to the effect of water bouyancy, the felt effect of gravity > is less than what we experience. Funny coincidence, isn't > it. Hmm, well not exactly a coincidence. But the larger whales are *many* times larger than the largest Sauropod. Also there is more food available in the oceans, so that might also have something to do with it! -- Sarima (Stanley Friesen) UUCP: {ttidca|ihnp4|sdcrdcf|quad1|nrcvax|bellcore|logico}!psivax!friesen ARPA: ttidca!psivax!friesen@rand-unix.arpa