A New Spin (cont'd)
'What is
this?'
1. The Bigger They Are ...
During the court case following the super-tanker Exxon Valdez environmental
disaster, it was revealed that the crew initiated a change-of-course maneuver
which would have taken some 45 minutes to complete (it was never
completed since the ship ran aground shortly thereafter). A kayak could
have turned around in a matter of seconds, once on a dangerous course,
but for a super-tanker it is just not possible.
Why? Physics.
Recall a high school
experiment: a mass hanging on a spring
performing a Simple Harmonic Motion. You may recall that when the mass
was increased it still bobbed up and down, but more slowly. It was
said that as the mass increases, the Physical-System takes on a lower
Natural-Frequency.
Nature dictates that as mass increases, the natural frequency
decreases, and hence the system slows down (i.e., larger systems
changes are more slow than smaller ones).
A big bell has a low tone (a sound of a low-frequency) having slow-changes;
while a small bell has high tone (a sound of high-frequency) having
fast-changes.
The next time you have a chance to peer into a grand-piano's entrails,
notice that the strings on the left side (corresponding to the low keys)
are long and thick, i.e., having high mass (big) while those on the right
(the high keys) are short and thin, i.e., having low mass (small).
The same principle applies to animals. We intuitively associate a deep low-pitched
bark with a big dog and a high pitch as belonging to a yappie little fellow.
It follows that whether for objects or animals, the bigger they are, the
more sluggish they becomes.
2. Is There A Limit to Growth?
As animals grow in size there must be a point where they can no longer
sustain life since they become too slow to function. In order to test the
validity of this statement we need to conduct a little Thought-Experiment.
Love this low-carb stuff
Imagine a 100-ton plant-eater lying there on its fat stomach
amidst the lush vegetation which literally grows into its mouth.
All it has to do is bite mouthfuls of the stuff to feed itself.
Every mouthful it takes contains exactly the amount of energy in
vegetation his body expends Thus, the energy expended is equal to
the energy taken so it is in perfectly energy balance.
Now, let that animal grow to twice its size. In order to maintain
its proportion, it grows eight times in volume and weight
(it has to grow twice in length, twice in width... you get the picture).
Having grown considerably larger, the animal becomes slower as
seen above. Although, its mouth can deliver the required energy
in each mouthful, it does that much slower (at a lower-rate)
than needed. The energy balance is thus becomes unbalanced
(i.e., it doesn't get the amount of food it requires).
Hence, it will starve amid a pile of food, exceeding the limit to growth.
3. Planet Size Versus Animal Size
The implication is that mobile life forms must be able to function
at a minimal rate which limits how big they can evolve to on a
given plant size.
The plant size determines the animals size where the bigger the plant
the smaller are the animals. This constitute the rationale for the
dictate that animals maximum possible size is inversely proportional
to their planet size.
The big dinosaurs could exist only on a world many times smaller than Earth.
It therefor imply that Earth certain physical parameter, must have been different than
it is presently, to enable their existence.
4. What Made Giant Dinosaurs Existence Possible?
In one word: weight or rather, lack of it!
It is the weight, not necessarily the size, which gives rise to all the
restrictions discussed above. It was the weight that slowed down the mass
which hung on the spring in the high school physics experiment; and it is
the cause for slowing down the big animals and, of course, the ultimate
limit to their growth.
It follows that the existence of the big lizards in the past
their weight must have been much lower than what
their size suggests.
5. But Aren't Weight And Size One And The Same?
Not necessarily! You must have seen the grainy black-and-white video-clip
of an astronaut hopping like a jack rabbit with all his gear on his back.
His size hasn't changed on the moon but his weight has.
The big dinosaurs' size is given but their weight is only deduced. After
all, when their remains are dug up, they never come wrapped and labeled
stating their weight like a package of beef on the shelf of your neighborhood supermarket.
The weight is only estimated and is based on the size of the finding;
and on the assumption that weight was then what it is now. This assumption
could of course be wrong. As we have seen above, it is most
likely wrong.
The size of a single big dinosaur may have been equal to the combined
size of a herd of 20 elephants, but its weight must have been no more than
that of a single member of the herd, so that it complied with the limit-to-growth
and remained viable. Such an animal could roam around, forage and do what
elephants do today despite its huge size.
There is an added bonus to this. It explains how a giant predator could have
functioned. The weight of what is usually considered to be an eight-ton such a beast,
would proportionally fall somewhere between that of a lion and
a grizzly bear, which would render it well suited to its role.
6. Are We Talking About Changes in Gravity?
Partly but not entirely.
Generally speaking, gravity is responsible for a given body
weight. But this is somewhat of a generality. In fact there are two more
factors that participate in determining the weight. These are buoyancy
and centrifugal force.
Both of these factors act in diminishing the weight of the
body, but their effect is so minimal that it can be safely neglected.
The centrifugal force constitutes less than one percent of the force of gravity
and buoyancy even way less than that. Therefore, it is not a major
inaccuracy to consider gravity determining the weight.
This is the situation nowadays. If we are to investigate the possibility
that weight was different in the past, we ought to examine all the factors
involved, not just gravity, in order to try and determine the reason for
the lowered weight.
Let us examine gravity itself first. In order to bring the weight
of a big dinosaur to that of an elephant, gravity in the past had to be
one twentieth of what it's today. That suggests that the earth,
subsequent to the time of the dinosaurs, gained mass by either colliding
or somehow merging with an extraterrestrial body some 19 times its own original mass.
Experts, however, can point to permanent marks in the form of craters as a result of
collisions with very small objects relative to the earth. Therefore,
it's impossible that a collision with a body, 19 times more massive than the
earth, has not left any mark whatsoever on the earth's surface. Hence, an
increase in gravity must be ruled out as a cause for the weight change.
Next we look at buoyancy. Every object on earth is immersed in air (in essence,
a form of fluid). While the air could have changed throughout that time in
composition and concentration, it could not have changed in density in any
significant way to make much of a difference. Therefore buoyancy can also to be
ruled out as the cause for weight change.
The only factor that is left is the centrifugal force. Although there is no
direct proof that the centrifugal force was any different in the past,
there is equally no proof to the contrary. The mere existence of big animal
fossils may, by itself, constitute such a proof.
7. Centrifugal Force and Earth's Rotation
The centrifugal force arises due to rotation. The classic example is a
rock tied to one end of a rope. As the rope is held at the other end and
is being rotated fast in the horizontal plane, the rope becomes taut.
The centrifugal force tends to pull the rock away from the center of rotation.
Earth is rotating on its axis, even though as far as we can tell, it doesn't
move at all since everything around us moves at the same speed. However,
at the region of maximum speed any point is zooming-by at a velocity due to
the earth's rotation which exceeds that of a supersonic jet going at Mach-1.
The rotational velocity gives rise to a centrifugal-force which opposes
that of gravity. Consequently, its effect is to reduce somewhat the gravitational
pull and hence, the weight of any object on the surface of the earth.
As things stand now, the centrifugal force effect is minimal and is usually
neglected.
At the time of the dinosaurs earth must have been spinning on its axis
close to (but not quite) 17 times faster than it does today.
That left them with about five percent only of body-weight.
A faster spinning earth constituted a strange world indeed. It took only
around three-quarters of an hour from dawn to dusk.
But other than that not much of a difference. It was not possible to tell that Earth is
spinning faster more than it is today.
It did make all the difference for the giants
of that time though. It enabled them to carry on with their lives and function
as intended. The biggest land animal ever body-weight was just as much as an
African-elephant weight (which was the same limit-to-growth).
8. What Caused Earth's Spin Reduction?
There is no direct evidence and it may never be known for sure what caused
Earth's spin to slow down. All that can be done to answer this question is to suggest
a way that it is likely to have happened. The following is an attempt to suggest
such a cause which is purely speculative.
Consequently to the disastrous earthquake that struck Japan in 2011, it was determined that the earth's spin changed somewhat and the axis of rotation also shifted slightly. While these changes are very minute they are definitely measurable and, of coarse, permanent. That being the case, was it possible for an enormous earthquake and large motion of tectonic plates enough to cause changes to the earth's spin and axis of rotation which end the dinosaurs era?
9. Additional Implications
REJD's
observation that the atmospheric pressure would have been reduced as a
result of the reduced weight, brings to light an interesting point that could
explain why the dinosaurs remained cold blooded throughout their reign.
With hundreds of millions years of evolution under their belt, a question may
well be asked how come they never evolved from the "primitive" status of being cold blooded
to the more "progressive" state of being warm blooded. After all, warm blooded animals
do not depend for their function on the temperature of their environment and are able to
better cope with changes in temperature.
The extremely low barometric pressureat at the equator must have resulted in tremendous winds
blowing from the high pressure points at the poles and pushed on by the low-pressure
gradient throughout, all the way to the equator of that time. It's similar to your
occasional local weather picture, with centers of high and low pressure, but with two
big differences: the winds were permanent and must have been tremendously strong.
How strong were these winds is yet to be determined and such terms as "extremely"
and "tremendous" may turn out to be huge understatements. It would also remain to be
explained how the plants and animals managed to survive under such
a permanent storm.
Similar to natural convection that distributes the heat in a heated living-room (actually,
more like a gigantic forced-air fan) the possible effect of these perpetual winds was
to even-out the temperature throughout the globe so as to make it practically the
same at all latitudes. It probably was the same day and night and throughout the year's seasons.
"I did-it m---y way"
With such fixed temperature why bother to become warm blooded? A cold blooded creature is
by far more efficient from the standpoint of energy and food requirements. Animals
such as crocodiles and snakes are known to do with a single meal per several months since they
don't have an internal furnace requiring a constant feeding of fuel.
So, why didn't the dinosaurs become warm blooded? There was simply no need for them to do so.
The saga of the winds has farther implications.
The low-barometric pressure caused wind may also bring the big birds, of that time, to finally
come home to roost.
Any attempt to rationalize cold blooded birds is in trouble.
Birds expend very high amount of energy in the process of flying. It is not likely
that a cold blooded bird could posses the ability to generate the power
required for flying. Big birds, with a wingspan of up to 40 feet (12 m),
are even in a bigger trouble to place.
The pre-historic age biggest animals, of all sorts, can have a
one-to-one correspondence to the big animals alive today. The biggest
plant-eaters correspond to the big elephants. The big predators correspond
to something between the lions and the grizzly bears. However, applying the
same factor of weight reduction to the big birds would imply that there
should be alive today birds with a wingspan of 15 feet (4.5 m).
Not only those birds don't exist at present, it is unlikely such large birds
could fly at all. It seems to suggest that the large pre-historic birds were
too big even for their own time and their existence can't be explained on the
same basis as the rest of the big animals.
So what is going on here? Is the whole theory in big trouble? Not, if we
consider the unique winds which were constantly blowing.
Anything could
take flight in such a wind provided it had a sufficient wingspan appropriately
oriented for takeoff and maintaining lift. Much like
a '747' flying, with one difference -- the '747' capable of generating
its own wind.
It is questionable if these flying animals deserve to be classified as birds
altogether, since they most likely didn't propel themselves by flapping their
wings, but simply relied on the power of the wind to glide. Much like a sailor,
who can travel in any desired direction -- including against the direction of
the wind -- by skillfully deploying and orienting the vessel's sails,
these giant birds could "fly"
using their elaborate wings (probably, more of sails than wings) without expending any significant energy
in the process.
"Look Ma! No flapping!"
10. Conclusion
This theory suggests that dinosaurs existed under Earth's different physical conditions.
A faster-spinning Earth reduced effective weight, allowing massive creatures to thrive.
When those conditions changed, their world and their dominance came to an end.
Joel Tepper P.Eng.
telejt[delete_me]@shaw.ca
Revised since originally posted on 31 of December, 2003.
Any Comments?
If you care to comment on any of the above you can email your comments
to: telejt[delete_me]@shaw.ca
Your comments will be posted in the Comments section.
Acknowledgment
The author is indebted to Paul R. Abrol, P.Eng. for his helpful critique and for initially
editing the manuscript.
Documented evidence from independent sources
The observations and findings bellow are provided by independent sources.
This information seems to support various aspects proposed in A New Spin.
If you are aware of any other factual material that can serve for a
compelling evidence, please advise at:
telejt[delete_me]@shaw.ca
From:
http://www.abc.net.au/science/news/enviro/EnviroRepublish_1239175.htm
[Cached]
"...The fossilized tree rings in the Glossopteris trees revealed they grew steadily
each summer and abruptly stopped for winter, as if a switch had been thrown.
"They probably reacted to light (rather than temperature) to switch off,"
said Cantrill..."
(David Cantrill, curator at the Swedish Museum of Natural
History in Stockholm, http://www.nrm.se/welcome.html.en)
[Emphasis added, J.T.]
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From:
http://www.polar.org/antsun/oldissues2002-2003/Sun111002/dinosaurs.html
[Cached]
"...Paleobiologists Tom and Edith Taylor found forests of fossilized
tree stumps... Despite the dark winters, the trees had growth rings
10 times the size found on trees growing now in
Alaska. The Taylors were surprised to also find
cycads, a tree with a spongy trunk that now grows
in tropical areas..."
[Emphasis added, J.T.]
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From:
http://www.gi.alaska.edu/ScienceForum/ASF7/788.html
[Cached]
"...Within Alaska, there have been recently confirmed fossil
finds of hadrosaurs, or duckbilled dinosaurs, north of
Kotzebue ... the primary question still arises: even if the global
climate was far warmer then, how could these animals and the plants
on which they depended for survival have lived in an environment
where it's dark half of the year?
Continental drift, putting the lands in which the fossils lay
closer to the sunny equator, doesn't
seem to work--at least not for the High Arctic islands. Of all the
land masses on earth, they seem to have been among those that have
shifted the least. Could it have been a tilting of the rotational
axis of the earth, bringing more sunlight to what is now
the Arctic? There is no known mechanism to account for that..."
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From:
http://www.enchantedlearning.com/subjects/dinosaurs/dinos/Pterosaur.shtml
[Cached]
"Genus Pteranodon - 23 feet (7 m) wide wingspan [during the late Cretaceous period] ...It glided along rather than
flapping its wings..."
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From:
http://tornado.sfsu.edu/Geosciences/classes/lwhite/fly.htm
[Cached]
"...Birds have feathery wings that are attached to the forearm and hand and
Pterosaurs have membrane wings that are attached to 1 long finger."
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From:
http://www.geol.umd.edu/~tholtz/G104/10433phys.htm
[Cached]
"... some [dinosaurs] had means of rapidly oxygenating their blood to be "turbo-charged" and thus function temporarily as highly active animals."
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From: Paleobiologists Tom and Edith Taylor
[Cached]
"...190 million years ago Dinosaurs live in ntarctica Antarctica..."
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From: SCIENTIFIC AMERICAN, August 2006, page 30.
"...North Pole's mean annual temperature: -20 degrees C.
Temperature 55 million years ago: comfortable 23 degrees C."
(On the eve just about the "big-event". J.T.)
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From: SCIENTIFIC AMERICAN, January 2008, "Hot Spots Unplugged", page 89.
"...the direction of the [tectonic] plate motion suddenly changed some 47 million years ago ... motion of the solid earth relative to the planet's spin axis ..."
[Could the direction of the "old" motion match the change in direction of the "old" spin axis which happened at the same time just about? J.T.]
Comments
----- Richard E. J. Driskill's comments ------
Hmmm... cute.
The Earth is presently 24,901.55 miles in circumference, at the equator, at
sea level, and it's along that point it spins (rotates) at a rate of
1,040.4547 mph (mean speed), which is judged over a period of 23 hours, 56 minutes, and
4.09 seconds. If your claim of an increase in spin of 17 fold for the period
is extrapolated, that would mean the earth would have been spinning at the
equator at 17,687.729 miles per hour (all things being equal). In both cases the
poles, as pin points (minus any relative wobble) would experience a 0 mile per
hour spin rate. Additionally, the rotation rate would deliver periods of
light and darkness, that if evenly divided would span roughly 42 minutes and 21
seconds each. I fear this would play havoc on the photosynthesis process of most
plants (past and present), and you might want to check this out with a
botanical scientist. Due to the near constant twilight-like condition of the planet,
I would also extend that the lack of relevant cycles of heating and cooling
would have impacted weather conditions to the point that the planet would be
more arid than lush.
And now we come to something called escape velocity. The present escape
velocity for the Earth is 11.2 km/sec (25,053.69 miles per hour) and is the same
for a molecule of hydrogen or a huge dinosaur. Your aforementioned spin rate of
old would have induced a condition wherein 70.599% of the escape velocity at
the time (all things being equal) would have been negated. This would be in
direct reference to your comment on centrifugal effects upon weight, and by
extension, its interaction upon animal size viability. In fact it would impact
much, much more.
The atmospheric pressure (and all that that implies) of the planet would have
been catastrophically reduced (ballooning outward) to the point that ALL
cellular growth and design between the 2 periods in time would surely be quite
noticeable, including the internal bone matrix of long dead dinosaurs.
To the best of my knowledge, this has not been discovered to be the case.
[Author's note: actually it has been, albeit, somewhat indirectly and in the growth
of tree-rings instead. You can look it up
here. J.T.]
This leads me to conclude, that although your hypothesis is initially
interesting, it's unsupported in relative facts to the degree it becomes
implausible. BUT... I must say I am impressed with your thinking process. Never stop
banging at the door. ;)
Mr. Richard E. J. Driskill
Electromagnetic Spectrum Authority (retired)
Back to: "10. Additional Implications"
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-------- Matt Weed's comment --------
I enjoyed your article very much.
Could the earlier spin rate be attributed to the earth being much smaller than
it currently is? Similar to a ballerina pulling her arms, and thereby spinning
faster, could an ancient, smaller earth have simply spun more quickly due to
the fact that its mass was closer to the center point? However, would the
centrifugal forces on a smaller globe be cancelled out somewhat due to the
smaller angular size?
I have been reading many articles regarding the "Expanding Earth" theory, with
which I'm certain you're familiar. The theory itself is interesting, and
compelling, but I can't find any explanations to handle why such an expansion
would have occurred so recently (within the last 200 million years or so) and
given the generally acknowledged age of the planet, this would seem to be a
sticking point. I.E. why would the earth stay at a relatively small size for so
long, and then "suddenly" start expanding. Still, while the mechanism might be
unknown currently, it all seems to fit what you're postulating. Perhaps planetary
expansion is a common event in the evolution of planetary systems.
Some potential causative factors:
- A miniature black hole passes by the earth's orbit, and its strong gravitational
effect begins the "thinning out" process of our planet, and thus slowing down the
spin. I really can't see ANYTHING surviving such an event, as it seems the entire
planet would have been resurfaced in magma, but still...
- Moon capture - how long has our moon been in Earth orbit? Given its small mass,
it might not be capable of slowing down the Earth's spin in accordance with your
theories.
- Little green men?
Anyway, great article, well thought out, and I would love to hear your thoughts
if you have a moment.
Take care.
Matt Weed
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