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Modern methanobacteria.
"Life ain't always pretty."

I've been doing some investigation lately into early life on the planet.
The resources on the internet aren't bad. But there comes a time you
need to get to the journal articles and the textbooks.

Now, if you want to read the most recent Stephen King novel, you can
just go to the library and get it. Technical books are more of a
problem. Not only is there the question of whether your local library
even has a book or not (or could get it on inter-library loan), but
there's the problem of how long you can keep the book. If I need a
technical book, I usually like to buy it. This gives me the needed time
to go through the thing — which given my feeble brain might take some
months. And with your own book you can underscore and make marginal
notations for future use.

Thus I came across a book called Methanogenesis by James G.
Ferry. It looks like a very interesting book. It deals with the evolution,
metabolism, molecular biology, and ecological interrelationships of forms of
early bacteria (archaeobacteria) generally known as the methanobacteria.

But the price? Whoa! The book is a whopping $261 US. I had paid a pretty
high price in college for a couple of books. But the most expensive
books I had to shell out for in college were my Chemistry book and the
Handbook of North American Indians Vol. 12 that I used for my
Plateau Archaeology class, both of which came in at $135 each.

In any case, Methanogenesis is really beyond my budget. I found
another book instead that is more within my means, The Origin and
Evolution of Early Life
by Tom Fenchel. This one runs about $60. I
should be able to get it in February and go through the thing. In the
meantime, I'll continue with the internet resources.

Early life on earth can be viewed in two different ways. First, there
are procaryotic organisms, which do not have a nucleus. These organisms
probably preceded eukaryotic organsims, which do have a nucleus. It has
been speculated that eukaryotic organisms developed when two different
prokaryotic organism fused, with one organism invading the other and
living inside of it, with the inner organism becoming (eventually) the
nucleus. To my anthropological mind at least, this sounds like a pretty
interesting idea. But it is not really known whether it happened that
way.

Another way to look at early life is from the standpoint of respiration.
There are two categories for this — aerobic organisms which produce oxygen,
and anaerobic organisms which produce something other than oxygen.
Methanobacteria, as the name suggests, generate methane.

Modern photosyntheic organisms have a sophisticated chemistry involved
in respiration, in which complex sugars are broken down to produce oxygen.
Fortunately for we laymen, the chemistry of early life is a lot simpler.

For anaerobic methanobacteria, for example, respiration looks like this
(various intermediary steps omitted)

a) H2 + CO2 –> CH4 + H2O
b) CO + H2O –> CH4 + CO2

In the first case, the bacteria uses hydrogen and carbon dioxide and
produces methane and water. In the second example, the organism would use
carbon monoxide and water to produce methane and carbon dioxide. In
actual fact the water (H2O) in the second equation could be another
compound of the form H2X, such as H2S (hydrogen sulfide).

Now the interesting thing about this is that both methane and carbon
dioxide are what we would call today "greenhouse gasses." You'll hear a
lot of talk about both in discussions on global warming. But the early
earth in the late-Precambrian era was an extreme environment. It was ALL
global warming back then. But that was okay, inasmuch as most life was
anaerobic and didn't need oxygen to live. Today, we kind of need the
stuff.

The planet was about the same temperature in the late-Precambrian as it
is now. But that is deceptive, inasmuch as the sun was 20% dimmer. If it
hadn't been, the chemistry of the earth would have made it a very hot
place indeed.

Now most opponents of global warming argue from the standpoint that
there have always been oscillations up and down in the earth's climate.
But you really don't have to go that route. To determine what our
environment is turning into we only have to look at the chemistry.
Industry and the burning of carbon fuels, as well as agriculture, produce
the equivalent of anaerobic respiratory processes — they generate
greenhouse gasses which warm up the atmosphere. That's just simple
chemistry. It's hard to believe that people are still arguing about
global warming. "Garbage in, garbage out" goes the old phrase, and any
time you put garbage into the environment it's going to have bad effects.

One of the intermediary steps not shown in equations a) and b) above
involves the creation of CH2O, which is formaldehyde. Now if you were
to go around and ask people if it's okay to pump millions of tons of
formaldehyde into the atmosphere, I think it safe to say they would be
highly opposed to that idea. But in reality, methane and excess carbon
dioxide aren't any better.

And while the formaldehyde process may be more of an analogy, in the
overall balance between anaerobic and aerobic process of life on earth
it seems that homo sapiens sapiens have not been so wise over the
course of their history. Forget about the fact that there might have
been a warming period in the Paleolithic 60,000 years ago "equivalent"
to our own. What is really significant is that since the beginning of
the industrial revolution that we have been significantly affecting the
balance of things. What we have been doing, literally, is poisoning our
planet.

In the early days of life on earth, anaerobic life was dominant. But
eventually aerobic forms of staked out what you might call a small claim
and continued to live and evolve in spite of an extreme environment.
Both forms, anaerobic and aerobic, were able to live together in the
same environment. If those organisms hadn't succeeded at that, we wouldn't
be sitting here writing or reading this.

The evolution of life on early earth was a combination of many different
vectors. If those vectors would have been absent or different than they
were, life wouldn't have been possible and wouldn't have evolved.

Life is a miracle. It was at the beginning of the earth's history and it
still is. And you don't need to be a Creationist and reject scientific
evolution to see that.

There are plenty of miracles, even in science.

There is an idea floating around out there that Nature is very
resilient and if we let things go that everything will eventually be
all right. And there is a grain of truth in that. Nature is and has
proved itself to be very resilient over the geologic span of the earth.
But to sit around and refuse to correct our errors thinking that Nature
will simply "pull itself up by its own bootstraps" is naive in the
extreme. On the other hand, if we could come together across the planet
and think holistically and limit our excesses, then there is a good
expectation that after a hundred years or so that the earth's ecosystems
will recuperate. As for how likely it is that humans will do that, well,
I guess you have to look for the miracle there. Because it just may take
a miracle in culture, too.

Modern evolutionary theory tends to look at history as long periods of stasis
punctuated by brief bursts of change. We might not think that extinctions
may come all of a sudden. But in fact they do. And we are a part of that
process. To think otherwise is pure vanity.

"In my beginning is my end" wrote T.S. Eliot. It can only be hoped that
200 years from now that methanobacteria are not, once again, the main
species of life on earth.

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