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Say Hello To Occam's Bulldozer
I think the time is right to introduce all of you to the concept of "Occam's
I believe that people have the tendency, and tenacity, to see ideas as
supported facts (especially those of their own); Ideas which are really just
speculations based on a partial fossil record. Yes... It does seem to be a
really good idea that simple feathers evolved first and variations on these
basal structures helped out in individual environments. For fliers, this
apparently means those pennaceous-type feathers we all know and love, with
secondary flightless versions of theropods inheriting the splendor. It sure
would seem like this was the most likely path now doesn't it? It also would
seem logical to us to develop things in this manner. However... Homeotics don't
play that type of game peoples. Nature is a wicked old sod that often enjoys
showing us that the simple root WE pick is not always best or correct root we
thought it to be. Selection selects on changes that, as we all understand, are
in response to the environment. This leaves little in the way of allowing us!
o establish the coveted "A logical development over time" scenario.
Evolutionary "stages" are not viewing themselves as part of a series. They are
just looking for more immediate reproductive success. If in the end, the
results appear as "stages", which in hindsight we label as being a part of a
series of logical steps, we most likely ended up with a picture colored by the
human mind's need to see an overall reason that was actually not present during
the actual selection events themselves to begin with. I liken this to painting
by numbers... Trouble is... we only know how to count with whole numbers from 1
to 10... But the pictures we are trying to paint use decimals and fractions
that go up to 1,000,000.
A perfect example of nature giving us black-eyes comes in the form of the
evolution of the spiracle in fish. It was once thought that the spiracle
developed by the increase in size of the mandibular arches which then
restricted the first gill slit down to the size of the spiracle. Later, we were
beaten with baseball bats when we saw that the fossil record showed the
development of the spiracle FIRST, before the jaws. The spiracle was then
believed to have been selected upon because of the organism's need to have a
breathing vent of sorts while being buried in the mud. Other ideas have been
tossed about as well... But the end result was our immaculate logical sequence
being doused in gasoline and set on fire while the fossils laughed and made
goggly-eyes at us while performing a stupid little dance.
Another simple example that comes to mind would of course be the new reasoning
behind tetrapod limb development. Now we see limb evolution, not as elements to
help the creature get about on land, but as the product of an organism dragging
its still very fishy self through plants and rocks under water as it set up to
be an ambush hunter.
We need to realize that most of our logically constructed sequences make sense
only after we take into account a more complete fossil record, and not to try
and derive ideas from a limited fossil record and pass them in goodness as
facts. Let's sing all together now... "Little steps... Little steps... Homeotic
genes do as they bloody well please."
It is a fools game to play "Lets guess what variations in homeotic gene
expression can do!". Simple pathways are more for the human brain than for the
actual events which had taken place. We like the idea that 1 becomes 2 and
leads to 3. We like it so much that we have the bad habit of letting it rule
science where it should not. As a good friend of mine so elegantly puts it, "We
shall now call this type of thinking "Occam's Bulldozer"."
If we think about skulls and trends... The number one trend seems to have been
a reduction in complexity... Not an increase. I'm sure that most of us could
put together the pieces of a dog or human skull. But a basal fish?... Doubtful.
I am not implying that this is the same case as in feather evolution. What we
as a group are saying, is that parsimonious ideas are cool an all that...
But!!!... Lets respect reality first OK?... Old Man Reality continually backs
his Cadillac out of the driveway straight into and over us while we peddle our
neato-keen bicycles. This is a simple reminder that nature does whatever it
damn well pleases to do. We are left to hobble around with our legs in casts
trying to make heads and tails out of how we ended up face down in the street
with some crazy old man yelling that we shouldn't have been behind his car in
the first place.