Re: Did the increase of earth's gravity, assist the death of the dinosaurs?

On Apr 28, 3:47 am, rick_so...@xxxxxxxxxxx wrote:
On Apr 26, 4:11 am, "Jean" <jean.len...@xxxxxxxxxx> wrote:



chazwin a écrit dans le message
<1177674367.174091.23...@xxxxxxxxxxxxxxxxxxxxxxxxxxxx>...

On Apr 26, 9:44 pm, rick_so...@xxxxxxxxxxx wrote:
Triassic Period
- Plateosaurus; reasonably long neck, but muscular

Jurrasic
- Brachiosaurus; long necked.

Cretaceous
- Tyrannosaurus; Back to reasonably long muscular neck

Tertiary
- Indricotherium; Normal muscular neck

Quaternary
- Wooly Mamoth; Short muscular neck, trunk hangs down.

The Mamenchisaurus had a neck as long as 49 feet.

http://en.wikipedia.org/wiki/Mamenchisaurus

Since today, if you were to try and hold your arm out for 20 minutes,
you would soon see that gravity must be different today than it was
140 million years ago, when the Mamenchisaurus walked the earth in the
Late Jurrasic period.

And perhaps, it has fluctuated quite a bit of over the last 250
million years which has led to the change in neck size and shape until
we get to the present day.

Although the giraffe has a long neck, it has an over-sized heart, 2
feet long and weighing 25 pounds, which is needed to pump blood to its
head.

By contrast,

"We have determined that the left ventricle in a warm-blooded
Barosaurus, for instance, would have needed to weigh about 2000kg to
pump the blood its brain needed," he says. "This is impossible for at
least three reasons. First, it would be difficult to fit such a heart
in the available space; second, the heart would use more energy than
the entire remainder of the body, and third; the thick walls would be
mechanically so inefficient that they would expend more energy
deforming themselves than in actually pumping the blood."

And so then, if we consider that the argument for natural selection,
and evolution being that they grew long necks to reach leaves high up
in trees, yet if they raised their head, they would have passed out.

So the only logical solution is that gravity has changed. And perhaps
more than once, fluctuating, for who knows what reason, be that
collapse of the earth's crust as it cooled, or the gaining or losing
of moons, or asteroid impact, or what?

There must be some evidence in the ground that gravity has changed,
because presently things do not add up, and the current explanation of
the horizontal neck, does not work for all species of dinosaur who
clearly were not horizontally oriented as perhaps the Mamenchisaurus
was.

http://www.prehistory.com/brachios.htm
52 feet high.

There must be some evidence in sedimentary rock formations, that are
more compacted during those times when gravity was stronger, and less
when not, and it should be apparent in stream beds which can be
compared by the same sediment settling with some compacting more than
at other times, or something.

Gravity is not a thing that can fluctuate. There is no force in nature
that is gravity. The principle upon which we attribute "gravity" is
based upon the fact that particles of matter tend to gather together.
The nuclear bonds of atoms attract other atoms. The net result of this
fact is that proximity to very large bodies casues things to have
weight. This is what we call gravity and its survival as a constant is
wholly dependant on the nature of matter.
The earth cannot remain the same mass and have a different gravity
(rotational centripetal forces not withstanding). This is as certain
as a one inch Jello pudding not being able to support the weight of a
bus and hold its shape.
For the earth's gravity to change significantly, the mass of the earth
would have to change significantly. Thus if the earth were the size of
the moon its gravity would approximate that of the moon. Mars, a
planet of similar size, has a similar gravity to earth.
What "fluctuation" in gravity are you proposing happened in the past?
What the hell is "quite a bit"?
And what was the cause of this fluctuation?

Variation in the effect of gravity are caused by the following:
a) changes in latitude
b) changes in elevation
c) local topography
f) earth tides
g) variation in subsurface density
These changes would not be noticed by animals and can be only detected by
sensitive instruments.

If the rotation of the Earth has slowed this would mean an increase in the
effect of gravity. What effect
this would have had on organisms I do not know. Someone with nothing to do
and the back ground in physics
and geophysics needed could look up the estimates of the slowing of the
Earths rotations and calculate
the change in the acceletation due to gravity. I think it is unlikely that
the magnitude would be enough to have effected evolution.

JL

Well there has to be some explanation because this today...http://upload.wikimedia.org/wikipedia/commons/1/10/Sauroposeidon_dino...
is a physical impossibility.

It wouldn't be able to pump blood to its head and supporting the
weight of that neck vertically, would require a tension cable like a
building crane or a bridge.

60 feet tall, with a 40 foot neck.

If it was aquatic, then it would make sense. If the atmosphere was
somehow more dense, so as to make dinosaurs more buoyant that might
work. But it seems more probable, that the reduced gravity, made
growing large easier, and carrying that weight around easier and less
stressful on their heart and lungs which were quite small.

Some have argued that they were cold blooded, and required less blood
to the brain, but others have shown they were warm blooded.
And then there is the argument well they carried their heads
vertically, but gravity would wear them out in an hour at most.

So if they were in fact real, and not just written in as part of the
matrix without consideration for them actually being a real living
physical animal at some time, then conditions would have been
different.

And I don't know if the earths crust swelled, and had gas pockets
beneath it, if that would reduce gravity, maybe in conjunction with an
earth that spun more, and then if supervolcanoes erupted, and let out
that gas, if the earths crust might collapse, and cause a global
flood, and a mass extinction even, leaving the earth, with different
conditions.

If you consider Alberta, and the tar sands, in the middle of a
continent, perhaps when the earths crust collapsed, the water from the
oceans, swept a lot of bio mass into the center and deposited it in
Alberta.

There are a number of sites in North America where mass graves of
dinosaurs have been found all piled together as evidence of a flood of
biblical proportions.

FWIW

"There are two gigantic reserves in Alberta - huge tonnages of coal to
the west, and immense oil-sands reserves in the east. Between them lie
a mature basin and a permeable conduit. The coal-bearing beds and oil-
sand reservoir are within the same stratigraphic interval. Marine
sources appear inadequate. The non-conventional oil-sands bitumen
requires a nonconventional source. These are the coal seams and
carbonaceous shales of Late Jurassic to Early Cretaceous age. "

http://www.searchanddiscovery.net/documents/2004/stanton/index.htm

Well I don't know if that is helpful or not because you would think
the K/T event might be sufficient to collapse the crust and hence no
more dinosaurs because the gravity changed as a result of the
cataclysm. That would be only 65 million years ago though.

The P/T event (The great dying) that resulted in dinosaurs after that.

So some time between these two, maybe an asteroid impact, at an angle
might have sped up, the earth, in the P/T event, and then one at the K/
T event slowed it down.

It would have to be something dramatic, to kill off so many species of
animal.

If you consider an impact, or a volcano, that catastrophe is not as
deadly for a species as it would be to suddenly find yourself heavier
or lighter, no longer at the same depth in the sea and now deprived of
your food, or unable to lift up your head or pump blood to your brain.

So chances are it was not a gradual thing. But rather a cataclysmic
thing that can be traced perhaps to the mass extinction events.

.

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