A New Spin

Ask not how dinosaurs became extinct, ask how they existed (in the first place):

A New Spin

By: Joel Tepper


"I'm astounded by people who 'want' to know the universe
when it's hard enough to find your way around Chinatown."
-- Woody Allen

'What is this?'

-- The short answer:

It's an attempt to rationalize the existence of the giant dinosaurs in the past, even though their viability on the earth as we know it, is puzzling.

-- The long answer:

The following is not meant to introduce yet another theory for the demise of the dinosaurs. Rather, it explores the past basic physical parameters of the earth (not necessarily its environmental condition) that could enable animals, weighing some 100 tons, to thrive for millions of years. Inevitably, it will lead to conclusions about the dinosaurs' ultimate end when these parameters suddenly changed, but that aspect is only secondary to the more fundamental question, namely: given their enormous size, what made it possible for these creatures to live and function in the first place?

For the impatient:

Given what we know about the size and function of the various giant dinosaurs, their existence in the past is far from trivial. Can an eight ton predator   -- twice as big as the African-Elephant --   stalk and give chase to prey similar to how a lion or a tiger would?   (Apart from Jurassic Park III, that is.)

A simple analysis based on fundamental physics seems to suggest that nature sets a limit on how big animals can grow and still remain viable. This, in fact, refers to the weight of a creature rather than its sheer size which leads to an inescapable conclusion that despite their size these animals must have weighed no more than the corresponding big animals alive today.

From the three factors that determine the weight of an object, the only one that realistically may have been different at the time of the dinosaurs, is the speed of the earth's rotation. If we are to conclude that the earth was indeed spinning faster at that time, it would have given rise to a higher centrifugal force. This force, which opposes gravity, would cause these big animals to weigh no more than what their big counterparts weigh today and everything would 'fall in place', so to speak (including 40 feet wingspan, cold blooded birds).

'What is next then?'

The following will attempt to prove that big creatures of a given size could not have existed and functioned on the surface of the earth as we know it. A condition that could make it possible for them to exist, will then be outlined and a hypothetical event which could have changed this condition will be proposed. Last, but not least, a simple procedure that can be carried out by an informed reader to either prove or disprove the suggested hypothesis, in part or in whole, will be described.

(See also why dinosaurs remained cold blooded and how a bird with 40 feet wingspan could fly, in the comments section.)


  • i.   'What is this?'
  • ii.  -- The short answer:
  • iii. -- The long answer:
  • iv.   For the impatient:
  • v.  'What is next then?'
  • 1.   The bigger they are ...
  • 2.   Is there a limit to growth?
  • 3.   Not convinced yet?  What does rate have to do with it?
  • 4.   Why aren't any such big animals alive today?
  • 5.   What, then, made it possible for them to take their place in the earth's history?
  • 6.   But aren't weight and size one and the same?
  • 7.   Are we talking change in gravity, then?
  • 8.   What is centrifugal force and how could it affect the weight?
  • 9.   What is it that made earth's spin to slow down?
  • 10. Where is the proof?
  • 11. What is there left to do?
  •        Acknowledgment.
  •        Comments.
  •        Appendix: documented evidence from independent sources.
  • 1. The bigger they are ...

    During the court case that followed 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's just not possible.

    Why can't a super-tanker turn on a dime like a kayak can? In order to answer this question you may have to go back to your high school days. You may remember a physics experiment of 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 clearly dictates that as size increases, the natural frequency decreases, and hence the system slows down. Therefore, one would expect a big bell to have a low tone (a sound of a low frequency) i.e., having slow-changes; and a small bell to have high tone (a sound of high-frequency) i.e., 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 have to be.

    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'.

    Let's assume that this 100-ton plant-eater, which is often characterized as not having to move much, is just doing precisely that. Namely, it's just lying there on its fat stomach amidst the lush vegetation which literally grows into its mouth. All it has to do is just bite mouthfuls of the stuff to feed itself.

    Since the animal is cold blooded we can safely disregard any energy it may require for its normal bodily function. The only energy it expends is directed to its mouth muscles moving its enormous jaw up and down constantly in the process of feeding itself. Every mouthful it takes, on the other hand, contains exactly that amount of energy in vegetation so that the energy expended is equal to the energy gained and the animal is doing fine-thankyou.

    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). Since the jaws become eight times their size and weight, their muscles require eight times the energy in order to make them function. However, the volume of the mouth also grows eight times and every mouthful contains now eight times the amount of vegetation and energy, so there should not be any problem, right? Wrong!

    Having grown considerably larger, the animal becomes slower as we have seen above. Although, its mouth can deliver the required energy in each mouthful, it does that at a much lower-rate than the jaw muscles require to constantly operate. Consequently, unless that animal can transform itself to a government or to a major corporation (both of which can thrive on a deficit) it's doomed!

    3. Not convinced yet?  What does rate have to do with it?

    Let's make the following analogy to clarify the situation:
    Assume you moved into a big cottage which takes a truckload of firewood a day to keep warm. You hire a truck which delivers the needed firewood every day. Your place is nice and cozy.

    You then build some extravagant additions to the cottage and as a result it now takes eight-loads of firewood a day. You go ahead and hire a bigger rig that can deliver eight-loads in one trip. However, it does that only once a week instead of every day. Pretty soon your place is going cold.

    When it comes to animals, Mother-Nature with help from Physics, her daughter, together with granddaughter Engineering, seem to suggest that there is definitely a limit to growth.

    4. Why aren't any such big animals alive today?

    There doesn't seem to be any direct evidence to suggest that the limit to growth has been reached with the African-Elephant (at least no evidence that is likely to stand in a court of law) but there is plenty of circumstantial evidence. Perhaps the jury, employing just their common sense, can yet be convinced.

    It can be argued that it's just an accident of nature that no animal bigger than an elephant evolved since the age of the giant dinosaurs. The fact is that such animals actually have evolved although not on land. There are big whales alive today (provided the last one hasn't been hunted down, that is) which are nearly double the size of the biggest dinosaurs that ever lived!  It appears that some animals will always grow to the maximum size possible in their given environment. It suggests that the African-Elephant, small as it may be in comparison to the giants of the past, is just the maximum an animal can grow on land today and still remain viable. (Okay, somewhat of a leap of faith if not of logic here, perhaps a better case can yet be made with the following arguments.)

    A case can be made by looking at the constrains that a horse faces. As the saying goes: 'They shoot horses, don't they?' (At least they used to, let's hope they don't need to do that anymore.) This saying refers to a situation where a horse, which had the misfortune to injure a leg to the point where it couldn't bear weight, had to be euthanized to prevent it from dying in agony. It's not so much that the leg wouldn't heal, rather, the horse was not expected to live long enough for the leg to heal. The rationale was that since the leg can't bear weight, the horse will have to lie down and that will cause its lungs to collapse under its own weight. But, don't horses lie down from time to time?  Yes, they do, but they must be doing it for 'recreational purposes' only and for short periods. The fact remains that a horse has to spend its days (and nights!) standing up or it will be crushed under its own weight.

    If such a 'tiny' animal, by comparison, is facing such severe restriction to its 'lifestyle' due to weight; how can an enormous beast (whose weight is equivalent to the combined weight of an entire herd of some 200 horses) is expected to have any kind of lifestyle to speak of?

    A whale, comparable in size to a big dinosaur, which is pulled out from the sea and left on the beach is known to get crushed under its own weight. This should not come as a surprise on the face of it since the whale, literally, does not have any legs to stand on. However, it mustn't come as a surprise should a Structural Engineering analysis of a 100 ton dinosaur suggest that it had to be in the form of a giant centipede (if not a millipede) in order to adequately support such a structure. Similarly, it shouldn't come as a shock if a Material Strength study concludes that the legs had to be made-up from stone to begin with (on the live animal, that is!) in order to withstand the compression imposed on them by the overlying structure.

    Unable to substantiate these last statements, the jury will have to be instructed to ignore them. But even without these statements, the jury may already have serious doubts about the possibility that such animals could survive under the earth's present physical parameters, let alone function and thrive the way they did for millions of years.

    5. What, then, made it possible for them to take their place in the earth's history?

    In one word: weight or rather, lack of it!

    It's 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's the cause for slowing down the big animals and, of course, the ultimate limit to their growth.

    It follows that if we take for granted the existence, in the past, of the big lizards (the size of which can exist only on a world many times smaller than the planet Earth) their weight must have been much lower than what their size suggests.

    6. 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.

    Take the case of the whale discussed above. When its weight is stated it refers, no doubt, to its 'virtual weight' on land, not in its natural environment (i.e., in the sea) where it would be much lower (which by the way, explains how it could grow to such a size without violating the limit-to-growth).

    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's now. This assumption could of course be wrong.  As we have seen above, it's 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 beast, would proportionally fall somewhere between that of a lion and a grizzly bear, which would render it well suited to its role.

    7. Are we talking change in gravity, then?

    Yes and no! 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's not a terrible mistake to say that gravity determines 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. Take for example buoyancy. While its effect is negligible on land, it's a major factor in the sea and is the main reason for the weight of a whale to be what it is in its environment. (A way less than what it would be on land.) Buoyancy, therefore, should not be dismissed off hand without any consideration of its possible cause for the weight change.

    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) just as it would be if immersed in water for a sea creature. Buoyancy constitutes a major factor in water but only a minor one in the air. The reason is that the density of water is nearly a thousand times that of air. 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.

    8. What is centrifugal force and how could it affect the weight?

    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 tight. The centrifugal force tends to pull the rock away from the center of rotation.

    Now, those of you who are card-carrying members of the 'Flat-Earth-Society', will have to take my word for the next statement: the earth is rotating on its axis. How fast does it rotate? Fast is of course a relative term, and as far as we can tell, it doesn't move at all since everything around us moves at the same speed. But to compare it to, say, a ticket-carrying driver (speeding ticket, that is) it's way faster. In fact, 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. However, as things stand now, the centrifugal force effect is minimal and is usually neglected.

    As for everybody out there (with or without membership cards) you have to take my word for it that at the time of the dinosaurs the earth was spinning on its axis close to 17 times faster than it does today. How did the earth come to spin so fast? For all we know, there is no reason why it didn't do so from the "beginning" but more on that later.

    A faster spinning earth would have constituted a strange world indeed. You could have been persuaded, in such a world, to consider 'working from home' (also known as: 'Telecommuting' or, 'Telework') since by the time you would have made it to the office most of the day would have gone by. It would have taken only around three-quarters of an hour from dawn to dusk. But other than that, not much of a difference. It wouldn't be possible to tell that the earth is spinning fast more than than it's today.

    It did make all the difference for the giants of the time though. It enabled them to carry on with their lives and function as intended. (And there is no need to constantly try to 'shoehorn' them into functioning in the present state of slow spin.) The biggest land animal ever would have weighed just as much as an African-Elephant, a weight, which most likely was the limit-to-growth on land then, as it's now.

    9. What is it that made earth's spin to slow down?

    It may have been decaying with the passing eons, but that is not very likely (besides of not being very exciting). On the other hand, there is no reason to think that slowing down happened all of a sudden. In fact, there may not be any direct evidence whatsoever, and it may never be known for sure what caused the earth to slow down. All that can be done to answer this question is to suggest a way that it could have happened (perhaps even likely to have happened) and no more. Hence, the following attempt to explain the cause for the earth's diminished spin  is purely speculative (not that the forgoing lacked this element...) and if you don't buy it feel free to substitute your own version.

    Clearly, the hypothetical event that will be described below is in no way essential to the forgoing, the goal of which has been to outline the physical conditions which made it possible for the dinosaurs to exist on earth.

    So, here comes one take on a possible cause for the earth's slow spin (actually, while we speak, I can think of yet another scenario just as likely... See 'Comments' below). This one, however, may appear objectionable and bizarre to some. Remember: this is not an eye witness account; I was not there when it happened.

    In an article, titled: 'When Stars Collide', Michael Shara describes a hypothetical scenario whereby a super-dense star, such as a 'White-Dwarf', slices through the sun in a matter of a single-hour and continues on its way unperturbed.  Taking this at its face value, and assuming that such a small and dense extraterrestrial object happens to zoom very fast through the solar system, it may have proportionally passed by the earth in a matter of seconds.

    If you are all set to go and look for the marks left by such an encounter, good luck! There may not be any. The above article suggests that a grazing encounter, or a near-miss, can affect the stars involved and even fling a star from its location. Such an encounter could no doubt affect the earth's spin.

    The scenario for the earth loosing its fast spin is, therefore, set. A small object of high-density could have passed by the earth at a very fast speed (fast even for bodies of this sort) in a direction which happened to be opposite to the earth's rotation. To visualize, think of a wheel rotating fast in a certain direction. If the wheel is hit with the palm of the hand in a glancing angle opposite to the direction of its rotation, the wheel may slow down, come to a complete halt, or even end up rotating in the opposite direction.(Warning! Don't try it at home, just take my word for it, unless you happened to own a workman's heavy-duty leather glove.)

    This extraterrestrial body could have done just that to the earth by moving very fast in a direction opposite to the earth's rotation. Its trajectory could have been very close, but not too close to entangle itself in the earth's atmosphere. The effect of the encounter on this dense object may have been only of academic interest but the earth could well have been left with a new spin.

    This event could have lasted only a few seconds, but the hell it inflicted on the earth is just mind boggling and defies any imagination. Try to imagine a tidal wave which comprised the entire ocean as a result of the whiplash the ocean underwent. In fact, every object which was not firmly attached to the ground, including all the creatures that inhabited the surface of the earth, must have suffered a similar fate and  the bigger they were the harder they were hit.

    The biggest dinosaurs fared the worst. The force of the whiplash could have literally ejected them into space. They may have been completely incinerated in the atmosphere, fallen back to the ground scorched or, ended up soaring in space forever. The implication of this may be that no remains of 'live' animals were ever found and all the fossils ever uncovered have been of those animals which were already long dead and buried prior to this encounter.

    Terrible as the end of the big lizards may sound,  the alternative for them on an earth with a new slow-spin, would have been an agonizing death from lethal overweight with no hope for the future.

    10. Where is the proof?

    Should humans ever undertake space travel a' la Star Trek, they may come across a scorched dinosaur floating in space which would constitute the ultimate confirmation of the above scenario. In the mean time, it can only be used as a topic of a science-fiction story.

    There is, however, a shorter prospect for proving (or disproving) this theory. In order to visualize it we need to examine more closely the encounter outlined above and appreciate the fact that it would have caused not only a change in spin, but in all likelihood, a change in the axis of rotation as well. Hence, It would have established a new equator and new poles.

    The rationale is as follows: The earth was modeled above as a two-dimensional flat wheel (perhaps something like a bicycle-wheel). The reality is that the earth is a three-dimensional sphere, more like a playground ball than a bicycle-wheel. Also the trajectory of the body which zoomed by can be modeled by a vector having three components corresponding to a three-dimensional space. Although this trajectory was basically aligned with the earth's rotation and indeed pointed in the opposite direction, it was in all likelihood, pointing also sideways however slightly. This would have been enough to cause the ball to flip on its side and, therefore, make it spin on a different axis as well as with a different speed of rotation.

    The scenario of the trajectory having a small diversion from a perfect alignment is by far more likely to happen than a perfect alignment with no sideways component.

    In order to test the validity of this theory the following steps need to be taken. First, all the locations where the remains of the biggest animals (either predators or plant-eaters) were discovered are marked on a globe. Next, a straight line is drawn throug all these marked points. The line should go around the globe and close on itself. This line outlines the [old] equator which was in place before the onset of the catastrophic event described above. Accordingly, the [old] axis of rotation and the [old] poles were perpendicular to the drawn line.

    Such a line could tentatively be drawn from Australia through India, passing Europe, going through the Atlantic ocean to Argentina and from there passing by Antarctica back to Australia. This would possibly outline the [old] equator. While it may explain how dinosaur remains were found in polar regions, it misses locations such as in the USA where large animal remains were found. The remoteness of these locations from the [old] equator could perhaps be due to continental drifts or, the findings in these locations will turn out to be after all, of animals not as large as originally thought.

    Alternatively, the line could be drawn from Argentina passing through Oklahoma in the U.S. and from there through Alberta in Canada (places which are known for their dinosaur findings.)  The line continuous along the West cost of the Pacific Ocean and through Japan to Australia.  From there, it goes through Antarctica and back to Argentina. Alas, this option leaves India somewhat in the 'cold' to say nothing of Egypt which is too close to the pole for comfort (there have been findings of big animals reported in both of these places.)

    It would conceivably be possible to draw the equator differently in order to accommodate all the locations in question with the proper compensation for continental drifts or final determination of the weight of  the biggest animals found in these locations.

    For the next step of the test secondary concentric lines need to be drawn parallel to the [old] equator progressively toward the [old] poles. The first two of these lines next to the [old] equator, the one to the [old] north and the one to the [old] south, should join locations where the biggest animals found were not as large as those found at the equator itself. As more such lines are drawn, away from the [old] equator, each successive line should intercept locations where the biggest animals were smaller than at the preceding one. This process ends at a point where the biggest animal remains found is of a size comparable to that of a contemporary elephant. The rationale for this process is as follows.

    The centrifugal force which was in the past a major factor in determining the weight (equal to approximately 95 percent of the gravitational force) was at its maximum only at the equator and rapidly diminished toward the poles. Consequently, the weight along the latitude-lines increased just as fast which accordingly, allowed for only smaller and smaller animals progressively north and south away from the equator. As for an animal of the size of an elephant, we already know it can manage well without much help from any centrifugal force.

    This last step, as well as the first, are left, however, as an exercise for the reader. (Translation: The author of this blurb has no idea how one might actually go about it.)

    If you decided to carry out the test and tackle these issues, great! You stand to win no matter what.

    Well, did the distribution of animal remains pan out? Good show! You won. You just proved the theory. It didn't work out? You still win, since you managed to prove that the whole thing is baloney. You've got to admit though that a fast spinning earth provides a great way to lose weight. Beats going on any diet! There is just one more thing left for you to do in this case.

    11. What is there left to do?

    Carl Sagan, the celebrated late astronomer, teacher and writer used to recount a story from his childhood growing up in Manhattan. When looking up and seeing the night stars (it must have been still possible to see the stars in Manhattan nights at that time) he kept on wondering about them. Asking his 'know it all' adult neighbors 'what are the stars?' he would get the patronizing response: 'kid' – they would say in a deep authoritative voice of adults – 'the stars are just there!' Luckily for us, the kid didn't quite buy this 'scientific explanation' and the rest is history.

    It left for you to explain to me how animals, weighing some 20 times more than the maximum limit for survival on land, walked on the earth and how a predator, double the size of a full grown African-Elephant, got its prey; and please, don't tell me they just did and their time has passed.

    Revised since originally posted on 31 of December, 2003.

    Comments anyone?

    If you care to comment on any of the above email your comments to: telejt[delete_me]@shaw.ca

    Your comments will be posted in the Comments section (that is, provided that you don't happen to subscribe to the notion that it's the devil who planted the dinosaurs fossils in order to confuse the believers).


    The author is indebted to Paul R. Abrol, P.Eng. for his helpful critique and for editing the manuscript.


    To add a comment write to: telejt[delete_me]@shaw.ca
    You may, of course, also comment on the comments.  ;-)


    Another possible scenario for the changes to the earth's spin and axis of rotation

    Consequently to the disastrous earthquake that struck Japan, it was determined that the earth's spin slowed somewhat and the axis of rotation also shifted slightly. While these changes are very minute to the point of being almost a mere theoretical in nature, they are definitely measurable and, of coarse, permanent.

    That being the case, was it possible for a large enough motion of tectonic plates, to cause changes to the earth's spin and axis of rotation which end the dinosaurs era?


    ----- 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. See David Cantrill's findings in the Appendix section.   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)

    ----- Author's comments on Richard E. J. Driskill's comments -----

    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, by the way, 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 pressure 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. (Well, don't look at me. Didn't I tell you it was a strange world indeed?) 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.

    It's yet to be determined what was this temperature. (Likely, a comfortable midpoint somewhere between the temperature in Hell and that in Heaven.)

    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.

    But the saga of the winds doesn't just end there...

    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, in general, is in trouble. Birds expend very high energy in the process of flying. It's 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's 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 takeoff in such a wind provided it had a sufficient wingspan much like a '747' taking-off, with one difference – the '747' capable of generating its own wind.

    It's 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.

    – J.T.

    ----- B. Shipham's comment ------

    I like the general gist of it, especially as it has been established that the earth's spin is still (albeit minutely: approx. 2 seconds every 100,000 years) slowing. There is one thing that I just can't really buy into: your theory concerning the astronomical body that passed by the Earth thus slowing its spin is plausible enough, I guess, however, the fact that it tilted the earth's polar axis is somewhat tricky. After all, this implies that at some point something else of a similar magnitude occurred which exerted just enough force to halt this motion again. Otherwise, why should the earth not still, even if ever so slightly, be rotating around a lateral axis in addition to its polar axis? The sun's gravitational pull on the Earth can't be responsible for a slowing of rotation around an axis that lies - more or less - on the plane of the earth's orbit. But considering that the Earth is not rotating around a polar axis that is parallel to that of the sun, then the direction of the polar shift your theory is based upon implies that that its axis must lie (at least fairly closely) parallel to the plane of orbit.

    Just a thought... ;)

    B. Shipham

    The author's response:

    One way of looking at that is, indeed, earth keeps on rotating around (the old) lateral axis and this rotation is what constitutes our present earth's spin.

    One thing is for sure: it can not spin on one axis and at the same time rotate also on another. Gyroscopes (of which the earth is one) just don't do that!

    The celestial event that caused all of that shifting of spin is rare enough. To consider another similar event would be too much even for this author, don't you think?

    Nice try, but no cigar.

    – J.T.

    -------- 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

    The author's response:

    Could earth, somehow, undergone an expansion which would account for the spin slowing down? If so, how do we account for the likely shift of the spin axis?


    ----- Peter Steinbach's comment ------

    I'm still spinning :-)

    ----- Joe's comment ------

    My comment was simply to say that I find the observation that large dinosaurs would be too heavy to survive interesting. I agree with the physical basis described in this article.

    ----- Ian Tulloch's comment ------

    Thank you for putting New Spin for public consumption. A very interesting reading ... Have there been any developments on the subject?

    Ian Tulloch, (an interested observer)

    Another possible scenario for the changes to the earth's spin and axis of rotation

    Consequently to the disastrous earthquake that struck Japan, it was determined that the earth's spin slowed somewhat and the axis of rotation also shifted slightly. While these changes are very minute to the point of being almost a mere theoretical in nature, there are definitely measurable and, of coarse, permanent.

    That being the case, was it possible for a large enough motion of tectonic plates, to cause changes to the earth's spin and axis of rotation which end the dinosaurs era?


    Appendix: 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 (telejt@shaw.ca).


    From:  http://www.abc.net.au/science/news/enviro/EnviroRepublish_1239175.htm

    [Cached: http://www.webcitation.org/5Ym2Hugyl]

    "...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..." [Emphasis added, J.T.]
    [See: "Author's comments on Richard E. J. Driskill's comments" J.T.]

    (David Cantrill, curator at the Swedish Museum of Natural History in Stockholm, http://www.nrm.se/welcome.html.en)


    From:  http://www.polar.org/antsun/oldissues2002-2003/Sun111002/dinosaurs.html

    [Cached: http://www.webcitation.org/5YmIO99dj]

    "...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.]
    [See: "10. Where is the proof?" J.T.]


    From:  http://www.gi.alaska.edu/ScienceForum/ASF7/788.html

    [Cached: http://www.webcitation.org/5YmEE4RBH]

    "...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..." [Emphasis added, J.T.]
    [See: "10. Where is the proof?" J.T.]


    From:  http://www.enchantedlearning.com/subjects/dinosaurs/dinos/Pterosaur.shtml

    [Cached: http://www.webcitation.org/5YmZCFS0E]

    "Genus Pteranodon - 23 feet (7 m) wide wingspan [during the late Cretaceous period] ...It glided along rather than flapping its wings..." [See: "Author's comments on Richard E. J. Driskill's comments" J.T.]


    From:  http://tornado.sfsu.edu/Geosciences/classes/lwhite/fly.htm

    [Cached: http://www.webcitation.org/5YmFJVF9V]

    "...Birds have feathery wings that are attached to the forearm and hand and Pterosaurs have membrane wings that are attached to 1 long finger." [See: "Author's comments on Richard E. J. Driskill's comments" J.T.]


    From:  http://www.geol.umd.edu/~tholtz/G104/10433phys.htm

    [Cached: http://www.webcitation.org/5YmGoQCPi]

    "...some [dinosaurs] had means of rapidly oxygenating their blood to be "turbo-charged" and thus function temporarily as highly active animals." [See: "6. But aren't weight and size one and the same?" J.T.]


    From: Paleobiologists Tom and Edith Taylor

    [Cached: http://www.webcitation.org/5Ymg67xMG]

    "...190 million years ago Dinosaurs live in Antarctica..." [See: "Where is the proof?" J.T.]


    From:  SCIENTIFIC AMERICAN, August 2006, page 30.

    "...North Pole's mean annual temperature: -20 degrees C.
    Temperature 55 million years ago: (on the eve of the "big-event", just about, J.T.) 23 degrees C."
    [See: "Author's comments on Richard E. J. Driskill's comments" J.T.]


    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? (See: "Where is the proof?")  J.T.]