by Brad Jensen brad@elstore.com
Continued from Part I
There's an interesting phenomenon in our Earth/ Moon system. The tides on Earth are causing the Moon to accelerate in its orbit and gradually move farther and farther from the Earth. The bulge of water that is the tide results in a gravitational pull on the Moon that speeds it up.
I think the same thing happens with the Sun and Jupiter, except that the bulge is on Jupiter. This tends to accelerate Jupiter and move it farther from the Sun.
However, Saturn is in the way, and tends to slow Jupiter back down. In effect, the Sun is transferring momentum to Jupiter, and Jupiter is transferring momentum to Saturn. Meanwhile the gravity of Jupiter is helping to hold the asteroids and the inner planets
in fairly stable orbits.
In the meantime, interstellar debris continues to pass through the system. I do not think it is any accident that Pluto's orbit crosses Neptune. I think that in the natural course of things,
perhaps in several hundred million or a few billion years, Pluto would be where Mercury is now.
Suppose that 66 million years ago, you have an Earth with a thicker atmosphere and a Moon that is much closer to the Earth than it is today. Suppose a lot of material comes through the
solar system at once, like an interstellar shotgun blast. Some material hits the earth, in the form of multiple large meteorite strikes. A lot of that kinetic energy turns into heat, and the
atmosphere expands. Perhaps meteors also strike the Moon, and it decelerates a small amount, coming closer to the Earth. Or perhaps the orbit of the Moon is affected, and temporarily
becomes more elliptical, coming closer to and farther from the Earth. A large body passing near the Earth/Moon system could have this effect without ever bumping into either the Earth or the
Moon.
In any case, the Moon starts stripping some of the atmosphere from the Earth. (Actually what happens is the gravity of the Moon accelerates atoms and molecules of gas in the upper atmosphere, so that they reach escape velocity.)
Some of the water vapor in the atmosphere of the Earth is scooped up temporarily by the Moon. A small part of the vapor freezes and falls as snow on the dark side of the Moon. As the moon turns, the snow evaporates and then refreezes. Most of it escapes into space. A small part of it collects in areas of permanent darkness, at the poles of the Moon.
But the major effect of this, as far as we are concerned, is that
the atmosphere of the Earth suddenly becomes thinner. This is in
a matter of decades, centuries, or at most a few hundred thousand
years. The mammals' main competitors for environmental niches,
the dinosaurs, suddenly are short of breath, if they can breath
at all. The animals that are adapted to higher altitudes, which
are the mammals and one group of birds, are suddenly adapted to
everyday conditions. Dinosaurs on land and sea, and some of the
dinosaurs that have become birds, have their Last Gasp.
So a type of animal that evolved for a niche environment of thin
air and rapid temperature variation, becomes the breeding stock
for the suddenly changed conditions. The animals that evolved to
take advantage of high oxygen content (by today's standards)
don't have time to evolve for the sudden new condition. The
missing mass of the universe, the planetary pieces from between
the stars, has changed the course of evolution. If it hadn't
happened, we'd all be speaking Dinosaur. (That is a joke.)
Can we find proof of this? I think so. Maybe all we need to do is pressurize a chicken. Perhaps we can find unique but dormant parts of avian DNA, by comparing it with mammalian DNA. Perhaps there are geologic studies that can tell us about atmospheric pressure at the KT boundary. Perhaps there are fossil shorelines that can show us the extent of tides at that time.
(Note: January 2005. Since posting this two years ago, I've read that
they have determined that the percentage of oxygen in the atmosphere prior to the dinosaur's demise was much higher than it is today. I remember the figure as 54%, where it now is roughly 25 or 33% [I don't remember the exat figure now.] So the linchpin of my theory seems to be established. I don't know if this was known when I originally published this in the newsgroups, but I was unaware of it at that time.)
If this speculation is true, perhaps in a thicker atmosphere the early dinobirds could fly with smaller wings. Perhaps the larger dinosaurs could get more energy from less food, explaining how they could live with mouths too small to feed themselves with by our current way of thinking. Perhaps the higher metabolism lets them grow faster, explaining how some of them could get so big without dying of old age first.
It may very well be that the dinosaur-killing event was a blessing to mammalian evolution in more ways than one. It is likely that the unique mutation that made the mammals adaptable
to higher altitudes and therefore greater temperature variations, was hair. Over the course of millions of years of evolution, the dinosaurs couldn't come up with anything to preserve body
temperature so that they could expand into the mammal's environmental niche.
(I realize I'm discussing evolution as if it were intentional, I'm only doing so as a convenient shorthand.)
Then finally, they came up with feathers. Feathers, like hair, were an adaptation that serendipitously provided insulation (although I think both feathers and hair were
originally selected as a method of cooling, not keeping warm.) So the dinosaurs began living side by side with the mammals at high altitude, perhaps for the first time. Feathered dinosaurs first
developed soaring, then flying, as they hopped around in the mountains, in pursuit of or being pursued as, prey.
The most important idea to come out of all this speculation is that the solar system is a much more dynamic system than we have considered it to be. We know now that life can exist anywhere there is liquid water. That might be at great pressure deep in the atmosphere of a gas giant planet, that later becomes a small stony planet. It may be that the effect of life over billions of years, is to strip the dense atmosphere of such a planet. It may also be that the orbit of the Earth around the sun has changed significantly during the existence of life on Earth, which might explain why life didn't change very much for a couple of billion years.
Perhaps the life-induced 'evaporation' of our heavy atmosphere upset the orderly process of planetary progression and saved us from the solar hothouse that otherwise would be our destiny.
It is a strange idea to consider that microbes may be a factor in the evolution of astrophysical systems, but there you are.
There is also an idea that I call Ontological Laissez Faire. Over the course of billions of years, if there is nothing to prevent something from happening, it will happen. So ice accumulates on
the Moon, and life accumulates on Earth.
I do think, with 400 quadrillion planetary systems out there, that the same conditions that have occurred in our solar system, are occurring other places, even as we speak.
In any case, at the end of this philosophical speculation, I would like to remind my readers that this is not scientific theory, although it may lead to such efforts on the part of other people. If you turn this in as your school report or as part of a term paper, the teacher will probably make you sit in the corner.
For those of you who think that the Earth appeared suddenly on a Thursday afternoon in 4523 BC, I'd like to point out that I do believe in God, and I can't argue with Paul the Apostle when he says that the stories in the Bible are allegories. I do not think the idea that 15 billion years of orderly development have led to the existence of man, decreases either the glory of the Creator
or the dignity of man in any degree. We are here to love and be loved.
I apologize to those of you who find these speculations fantastic and irresponsible. I will say I went so far as to leave out my ideas of quantum transmutation and oil on the Moon. Why don't we see gravity waves? All those interstellar planets are damping them out. Don't get me started.
I am in a bit of a hurry to present this. My last fantastic idea was starving hurricanes by spreading oil on the ocean to cut heat transfer, and now I find that MIT is planning to do this. So I want to present these crackpot ideas before I wake up and read about them in the newspaper. There's an earlier and less developed version of this discussion in the newsgroup archives, go to deja.com and search for my name.
It would be a really nice idea to put an asteroid deflection system on the Moon. An asteroid doesn't have to hit the earth to affect the climate.
Might we see planet-sized objects as comets, or even hitting the sun, in the next couple of thousand years? I wouldn't say no. If you think people got excited about Y2K, wait till you see the response to this sort of event!
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