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

Jean wrote:
....
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.

The effect is still at the level that those sensitive instruments are needed save when the moon first formed. However life started after the moon formed. At that time (so I have read) the length of the day was about four hours. Without relearning the math and running calculations the moon would have moved to higher orbit and the day lengthened rapidly at the beginning and slowing with time. The math is only needed to calculate the rate of change.

The earth is about 4.5 Billion years old. Only about 500 million years ago did life appear on land in the form of more than algae. So the greatest part of the day lengthening was over. Thus the effect of centrifugal force reducing the effect of gravity was still in the range of those very sensitive instruments. In fact it was in that range when the moon formed but then we have to go into how sensitive is sensitive. If your time machine took you then you would not notice it.

As long as life is in the water it does not matter what the gravity is. So by the time things with stems and legs appear on land there is nothing of interest to consider as to the magnitude of the apparent force of gravity. Of course if someone finds something biological that is affected by gravity variations in the expensive equipment range all bets are off. But certainly it would have nothing to do with legs and plant stems/trunks.

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