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Re: BCF etc



<<- a very high percentage of what appears on the list is speculation - 
including all the cladistic inferences.>>

I agree with that most that appears on the list is speculation, as all 
things are in paleontology to an extent, but there are degrees to which 
one can speculate.  If one makes a theory that is based on hypothetical 
(imaginery) arboreal creatures of there is no fossil record, that is 
pure speculation of the worst kind.  If one tried to prove that the 
antorbital cavity of archosaurs accomodated an airsac, we have fossil 
and neontological evidence that makes the specualtion *less* to 
nonexistent. 

>Consider a wall at the y axis (x=3D0), and a body with a centre of =
>gravity at (x=3D1, y=3D2),  and a strut from this point to the wall at 
=
>(x=3D0, y=3D1), and another below it to the wall at (x=3D0, y=3D0).=20

Dromaeosaurs had a brace (their distally stiffened tail) and arms to 
hold them onto the wall.  

>The paedomorphosis argument has been refuted.

As have most theories. 

<<(. . . both by the argument on general principles by myself and George 
(in his case, many, many times) and again by Darren's very detailed 
approach.  We have to rely on people being reasonable and accepting when 
an issue has been settled.  It's not really possible to prove anything 
in this subject but without some willingness to accept when something 
that is as dead as the P thing is, there's no point saying anything at 
all.)>>

So far Darren has come up with the best alternative counterargument, and 
I am glad that somebody did make a counterargument.  But what Darren did 
not do was "kill" the paedomorphosis argument, I'm sure he would be the 
first to admit that.  What he did was cast doubt on the hypothesis.  But 
let me point out that the features can still support paedomorphosis, 
because all the features of ratites can be considered juvenile features.  
Based on what we know about the ontogeny of birds I think that the issue 
is not closed and the facts *may* *possibly* *tenatively* support the 
paedomorphosis argument (feel free to contradict me everybody, 
especially Darren).  

Matt Troutman

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