Last night I pulled out and dusted off my Microbiology text and found
myself typing and summerizing applicable sections for over four
several hours. (You should see what I do for fun :)). The details
are in the next post if you want them.
I still am doing more research on it, but here is some salient
points. I found was that my memory of this text was very good and
that not only is that "rare" intron really rare in the
Archaebacteria, but only found in part of the Archaebacteria branch
that one scholar calls for it to belong in a FOURTH grouping apart
from Eukarotes and Eubacteria and rchaebacteria. I have a climate
based reason why this is so, as well.
If you want to help in this further research, there is a paper [G.J.
Olsen, 1988, Cold Spring Harbor Symp. Quant. Biology 52:825] that if
you could find it would be helpful. It is a family tree using 165
rRNA mutations with a scale bar correpsonding to a 0.1 nucleotid
substitution per sequence position. The tree is unrooted but the
groupings of three to four are clear and the closest to the
"progenote" is . . . drum roll . . . the methanogens. (Okay, drum
roll from my perspective.) But this is just like DNA evidence in
murder case--really powerful stuff.
There are three main branches of Archeabacteria. The only intron
found so far was in the sulfur "branch" and one scholar for this
reason and a few others (we are talking paleo biology via genetic
analaysis) wants to put these sulfur extremophiles in a new group. So
you would have essentially have eukaryotes or complex creatures to
include humans, bacterias, methane making and salt loving
extremophiles, and the sulfur loving extremophiles. According to G.J.
Olsen's work, the salt loving extremophiles are more related to the
methanogens but also distant. Bacteria and complex life are very very
distant. The very closet example to the "progenote" (least amount of
mutations) of methanococcus I found some references to methane making
in marches and eustury and oceans! See:
Similar to oil, gas enters the environment due to both natural and
anthropogenic processes. Among the major mechanisms of methane
natural production in the biosphere, the decomposition of organic
matter by methane-producing bacteria (e.g., Methanococcus,
Methanosarica) deserves a special mention. These bacteria are able to
get the energy by reducing carbon dioxide in accordance with CO2 +
4H2 = CH4 + 2H2O reaction. These processes are typical for the silt
deposits of lakes and marshes and for marine sediments that are
lacking in oxygen and rich in organic matter.
My conclusions from my Gaia perspective? Very important evolutionary
idea here: once methanogens evolved the electrical insulation dynamic
of modulating cirrus they ALSO WOULD CREATE MODULATION GOING THE
OTHER WAY OF FEEDBACKS OF DRY CONDITIONS!!!!! Therefore, salt loving
archaebacteria retained a symbiotic relationship with the methanogens
and didn't have to evolve with as much complexity. Get it?
Sulfur loving extremophiles start to have to evolve some complexity,
but they too have a more distant symbiotic connection. Let's see if I
can describe it. This one goes more to tectonics and carbon cycling.
Just like there is a difference between an age where sweet crude
(without sulfur) and clean coal are produced, the Gaia feedbacks of
weathering would cause modulation to be dependant on the biological
conditions toward CO2 and H2 that the methanogens metabolize to make
methane. This would cause a volcanic pacing from weathering rates
(more CO2 means more carbonic acid means more weather and so forth),
but it could be done, and here is the key, INDEPENDANT of sulfur
Sulfur increases weathering, but not locally. Therefore, the
sulfur extremophiles required to evolve with complexity and could not
just evolve to efficiency like the salt loving or methanogenic
Putting this together relative to climate change it is very strong
circumstantial evidence of regional modulation of cirrus by
electrical fields and variable resistance of the hydrate fields . .