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Chapter I: So Here We Are
Kris writes: > Yes... It does seem to be a really good idea that simple
feathers evolved first [...] However... Homeotics don't play that type of game
David Marjanovic writes: >> Looks like they do, almost. That recent Nature
paper by Yu et al. messed around with gene expression to find out just that. <
Excuse me... Simple question here from the back of the class... How many times
in the history of science have we found that evidence seemed to point one way
(especially if thats what they were looking for), but later on new evidence
pops up to show otherwise? It is the reasons we have Piltdown men as well as
*Archaeoraptors* on our own front... It's not that *Microraptor*, as well as
the Enantio that it was fused to, do not pay a close resemblance to actual
fossils that we have now since found, and were in many ways, predicted to have
actually existed by various hypotheses on avian evolution... The main
problem... The Beast... resides in the thinking. This type of thinking is the
same as the people who think elephant legs are trees, and so they started
looking at the bark on the ground as evidences of their original idea...
instead of wondering why the tree just moved. I myself have ideas very close to
the ideas being stated on the many different fronts, but in no way would !
I try and say the evidence in suport of these ideas are much better than âif
the glove donât fit!â. To say we are attacking the ideas themselves is
completely missing the point, like a blind kid coming up to bat... Many of
theses ideas are very close to those who do not like the "Case Closed!" style
of dogma that goes on once an idea seems to have any evidence backing it for
more than a weekend.
Kris Writes: > Evolutionary "stages" are not viewing themselves as part of a
series. They are just looking for more immediate reproductive success. <
David Marjanovic writes: >> Of course, of course. Has been forgotten very
often. Doesn't contradict the above. <<
Actually it does... and the reason it is not being seen is central to the
problem. It seems to be inherent in the first place to look at the
hypothesis.... to start off small... and go big. When a study is done with this
as a mind set, it is very easy for people to put ovale blocks in round holes.
Kris writes: > It is a fools game to play "Lets guess what variations in
homeotic gene expression can do!". <
David Marjanovic writes: >> Fully correct. "Let's _try_ what variations in
homeotic gene expression can do!" is not, however. This is a scientist's game.
(OK, OK. Not that there weren't some foolish scientists. :-) ) <<
Kris writes: > If we think about skulls and trends... The number one trend
seems to have been a reduction in complexity... Not an increase. <
David Marjanovic writes: >> Yeah. And? Bad news for those who believed in
progress in evolution and equated more skull bones with progress. I doubt
anyone ever did both, however. <<
No one ever did you say? And how exactly could that be? Go around and ask
people not in the know about the subject. Take a nice old fashion head count of
100 people... Make sure they do not know about the fossils and then ask them
which seems to be the way a skull would evolve? More bones over time... Or less
bones over time?......... I..... on the other hand...... don't need to do such
a silly thing because I already know the answer. I have met many of these
people who would say âMore bones over time right? What do you mean less?...
How is that evolution?"
Simple fact... It is ONLY by way of the evidence that we know a reduction in
the dermal elements did indeed take place. Because it is known so well now, it
may seem to some as being obvious... Touble is... It is not... Just as it was
only after the fossils were found did the idea of big brains in humans coming
before bipedism go up in flames.
For us... It is not that we do not have fossils... The big issue here is that
we do not have fossils that show a series. This leaves those with ideas which
are not found as evidence to be able to sometimes see things that are not
actually there. For example... BPM 1-3-13 was said by Norell to show evidence
that pinnate style feathers evolved before flight. Then low and behold, here
comes another fossil called, and quite appropriately I might add,
*Cryptovolans pauli*... And what happens???? Here we have an animal that seems
to look shockingly like BPM 1-3-13, yet it shows feathers in such a way as to
scream flier. What I am saying is how about letting the fossil record show us
what is what this time around ok? Most had claimed dromaeosaurs as a pre-flight
version of the theropods that were related to the early fliers... Is this so
certain now? If so, are you ready to take that wager with fossils yet to
Chapter II: Occam's Bulldozer Cometh
It seems that some in the pool are still treading water and do not know just
what is meant by "Occam's Bulldozer"... and what is being implied. Others
seemed to have their water-wings on and have picked up on it right away.
The key here is the same with the term in general; Interpretation.
Interpretation is the main issue underlining most all of the said disscusions
Older versions of human interpretation, as in what was seen in the Burgess
Shales with say... *Anomalocaris*and how its earlier versions were separated as
different fossil animals.... is a classic example of seeing more than what is
shown in the fossils.
This was not only an idea of interpreting the fossils themselves, but it showed
how the whole subject of evolution itself was being interpreted as showing an
increase in body plans over time. We now see it as a decrease in body plans
over time, with the winners diversifying from there.
The fear that we have of being so biased in the future is thought to be
removed, at least in part, by the impartial method of "just the facts ma'am".
This is what we call Cladistics.
Cladistics, we believe, are a great tool to help us sort out the mess, but they
are still in their infancy. It seems people believe the errors of human
interpretation are not an issue when we use this method because all we are
doing is adding up the so called facts and letting a computer do the rest.
Cladistics can be too black and white in its current methods. This is not to
say that cladistics in general are a bad idea, as some have stated, but we do
need to, in my mind, make the traits a little more expressive of their true
nature. Of course this leaves us with a whole other bag of worms left open on
the table; Individual interpretation of those traits in issue. This is what
unavoidably happens when we use such an overly simplified version of a trait
and rating them as 0, 1, 2 ect...
Most used to state that how reversed a pubic shaft was in theropods was
something that dictated how "bird-like" that theropod was. This made it all
simple... Troodonts and oviraptors were not as bird-like as dromaeosaurs and so
This looks odd since we now see that *Archaeopteryx* most likely had a vertical
pubic shaft and dromaeosaurs in some cases had a much more reversed pubic
Yes... Truth be told... This may be reversals in some groups and it could be
possible that covergent evolution happened in closley related groups. What it
also can show is just what the rating of this trait is claimed to show;
Dromaeosaurs being more derived than *Archaeopteryx* in the direction of either
modern birds, or a side branch that is still further along than *Archaeopteryx*
One of the ways we have tried to work around this, is to let the gods of chaos
work their magic by adding up other traits that seem not to be correlated to
one another in any special way. This is done by adding up all the traits in
question that may change over time and rating them. This is done with as many
traits as possible that might help us correlate relationships between the
organisms in question.
For example, when we look at the list of characters for the phylogenetic
analysis of *Sapeornis* and other birds by Norell and Clarke (2001) in Nature,
we can see that trait number 159 reads; "Preacetabular ilii: (0) approach on
midline, open, or cartilaginous connection; (1) co-ossified, dorsal closure of
Now, the iliosynsacral canal is a canal formed by the iliosynsacral crest and
each canal is separated by the dorsal synsacral crest from one another. We see
the iliosynsacral crest as a median ridge formed by the fusion of the right and
left dorsal iliac crests with the dorsal crest of the synsacrum. Each canal is
roofed by the preacetabular wing of the ilium from its side and contains
epaxial musculature. The ventral wall of each canal is made up of the
transverse lamina which is the fused transverse processes of the synsacral
What is important in all of this is not all modern birds have this dorsal
fusion and sometimes this region is left open as it is in both pigeons and
The iliosynsacral sulcus, when present, is a furrow between the central
synsacral crest and right and left dorsal iliac crests. This is the same region
where the iliosynsacral crest is found in other birds that are no more derived
than pigeons and crows.
Let's think about this though... What rating should a pigeon or a crow get as
to maybe a seagull??? Should the first two be considered any less derived than
the last? What does (1) imply over (0)?
It is our belief this can be done with most of the traits that are used, and if
not, at least enough to throw off the final outcome by miles.
In short, when we warm up the ol' computers and put in the traits, they are not
adding up known facts... They are adding up opinions in style!!!
This is what is meant by "Occam's bulldozer"... The ability to think you are
being unbiased, but instead, you are just driving your opinions under the guise
of impartial facts.