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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.