[net.origins] more on 250 lb. birds

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