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Re: What is biomechanics? (or, The Truth About Flying Snakes - Was: Re: science and philosophy)



Colin McHenry wrote:

> ....If I was charged with turning a theropod dinosaur into a bird then
> _Velociraptor_ or _Troodon_ are not the sort of animals I'd be starting off
> with.  I'd be looking for a small insectivorous thing scurrying around in
> the forests.

Something like (but not specifically) _Microraptor_, approximately 41 cm (16")
long when mature?  _Microraptor_, a basal deinonychosaur, is the only mature
dinosaur yet found to be smaller than pigeon-sized _Archaeopteryx_.  Nobody is
saying that the later _Troodon_ or _Velociraptor_ evolved into birds.  I agree
with you that the immediate ancestors of birds were probably quite small.

>  I'm just amazed at how dogmatically some palaeontologists cling to

> cladistics, to the seeming exclusion of all other approaches.

What other approaches are cladists ignoring?  Could you be more specific?

> Discounting data because
> you don't like the method is ridiculous.

It depends on the method.  If the method is not scientific, then it should be
rejected.  Are you not rejecting cladistic methodology?

(John Conway wrote):

> >Besides, it is highly unlikely that we have -
> >or ever will - find the actual ancestor of the Eumaniraptora.
> >Eumaniraptoran fossils from the Late Jurassic are, sadly, very rare
> >indeed.
>
> What, you can cling to your belief

-- Replace "belief" with "hypothesis," please --

> that dromaeosaurs are actually ancestral

> birds because you don't think that we'll find any fossils that will
> contradict you?  How convenient.

Bearing in mind the processes of fossilization, it is easy to understand why
small, hollow boned theropod skeletons were rarely preserved, particularly in
forest settings.  In addition, some time periods are very poorly represented.
This is a reality we must deal with, regardless of our perspectives.  The
Liaoning and Mongolian deposits are exceptional in preserving multitudes of
detailed fossils of small, delicate terrestrial animals.  Only in such
remarkable settings can we glimpse the true diversity of small life forms that
once lived.  A complete understanding of the history of life on earth is and
will always be unattainable because the fossil record is far from complete.  New
fossils are welcomed, even if they upset long standing phylogenies.  Getting
closer to understanding the true history of life on earth is the whole point,
isn't it?

> Sometimes I really think Tracy's hit the nail on the head.  There are a lot
> of closed minds out there.

Scientists should be open to new ideas as new discoveries and studies come to
light.  The reality is, of course, that some people are more willing to let go
of cherished hypotheses than others.  Like it or not, scientists are only human
(and some are more "human" than others)!  ;^)

-----------Ralph W. Miller III