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various



--Original Message-- From: Jaime A. Headden <qilongia@yahoo.com>: Wednesday,
January 20, 1999 08:06 AM

>Betty wrote:
><
[snip]
>is it possible that (modern birds) might actually
>be derived/descended from more than one line of (prebird creatures)
>from this (major prebird creature group)?>
>
>  George has proposed this, and John Jackson, too; evidence?

No evidence of me having proposed that, I'm afraid.

I was of the opinion that a number of dinosaur ghost stem lines may have
been somewhat or largely arboreal, and I'm still sympathetic with that view,
particularly in the Triassic.  However I now think the first feather didn't
predate _Archaeopteryx_ by much and that only its descendants had them
though some of the larger ones may have lost them.  I think Ax or something
very shortly before gave rise to all birds plus the troods, ornithos,
tyranns., ovis, droms, avimimids & alvarezissississids.

This group minus obvious birds I will refer to as the K2FP's (Cretaceous
secondarily flightless pinnants).


JJ


--Original Message-- From: Tetanurae@aol.com <: Wednesday, January 20, 1999
05:11 AM

>Jeez.....  Does it never end?  Once again we hear on this list claims that
>Archaeopteryx had to be ancestoral to bird-like theropods because
>Archaeopteryx is from the Late Jurassic and bird-like theropods are from
the
>Cretaceous.

I don't think I've ever said they *had* to be (though I have said once or
twice that theory *isn't* established beyond doubt).

What is indisputable is that the stratigraphy is circumstantial evidence
pointing just one way.  People who love money pay others to take polls you
know, so statistics must have something going for it!


>
>Once again, I must point out that there are quite a few Late Jurassic
>coelurosaurs which have to be the sister taxa to birds (Compsognathus,
>Coelurus, Ornitholestes, Koparion) and there are dromaeosaur teeth known
from
>the Middle Jurassic.

It depends which bird-like theropods you mean.  The ones you mention here
are quite bird-like and I would agree they are the sister taxa to birds, but
the ones I'm refering to are the K2FP's (see above).  I've made that
abundantly
clear in the past and it's spelt out in my website.  As for the drom. teeth,
Chris Brochu told us that the croc. lines, which are much less disputed than
theropods, allow us to say with some confidence that teeth are not
particularly reliable as diagnostics, at least for crocs.


JJ


--Original Message-- From: Philidor11@aol.com <: Wednesday, January 20, 1999
11:54 AM

>In a message dated 1/19/99 11:16:46 PM Eastern Standard Time,
>jjackson@interalpha.co.uk writes:
>
><< For a potted version of my theory and comparisons with others, see:
> http://www.geocities.com/CapeCanaveral/Hall/2099/DinoTheories.html >>
>
>I saw.
>Strangely, given the undefined references and highly telegraphic style
[snip]
>Well, interesting reading, but I have to say, 'Wants expansion.'

It's just one page of a four page sub-site, the whole of which may be
accessed through:
http://www.geocities.com/CapeCanaveral/Hall/2099/DinoKabin.html

I'm sorry you haven't had the opportunity to discover this before.


>As I read it, I thought to myself, suppose archaeopteryx became a
decorative
>brick, or whatever material that limestone was supposed to become?   Which
>theories would still be presented and how would they be changed?  Another
>question, what would be different if Archie never evolved?  One possible
>answer is not much, particularly if whatever Archie's stem stock was
continued
>into the Cretaceous.


This is really interesting, and something I haven't yet thought through
fully.  What if nothing had changed except Archie hadn't been found?  Well,
the similarities between the Urvogel and the K2FP's wouldn't have been so
apparent.  I would still have guessed birds arose around Ax's time though,
but I
would have probably been a BAMM supporter, as would, I guess, Greg and
George, though BAMM only arose in the light of Ax/mani similarities.  The
discovery of Ax is thought to have had some influence on ideas in the 19th
century.

If Ax nor feathers had ever evolved at all, I guess there is a small chance
we'd have had pterosaurs around today.  Bats would have gone berserk in the
palaeocene.


>In fact, without Archie I think your approach, as I understand it, would
>probably be the consensus.>

You make me scratch my head more than everyone else on the list put
together!


Cheers,


JJ