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>Date: Thu, 25 Feb 1999 15:10:46 -0000
>From: "John V Jackson" <jjackson@interalpha.co.uk>
>To: <dinosaur@usc.edu>
>Subject: Re: Rahonavis....Both!
>Message-ID: <008c01be60d2$57a6cb20$e3e41ac3@default>

>--Original Message-- From: Larry To: Thomas R. Holtz, Jr.
><th81@umail.umd.edu>Cc: dinosaur@usc.edu : Wednesday, February 24, 1999
>08:47 PM


>>I`m not sure what Rahonavis has. I see very little written about it on the
>>net. I seem to remember it having those bony struts in the tail...(think I
>>saw it on TV). Anyway, I was just wondering if it wasn`t considered closer
>>to Dromaeosaur albertensis (lets say), than it is to the Archie group.

>"Closer" - that's their term.
>Your original notion, that Rahonavis and the droms split off some way along
>the Ax -> modern birds line is fine.

Actually, I was just "fishing around" for info to determine exactly where
they (BAMM) place Rahonavis in the scheme of things, trying to get their
viewpoint. I personally think that flying avian forms were around since the
mid-late Triassic, based on my acceptance of Chatterjee`s Protoavis as being
what he claims it is (if not on my own theory of a pterosaur-bird split in
the Triassic). So, a sickle-clawed form could have developed anywhere along
the way. I`m thinging that it probably was pre-Archie, and that Archie as
well might be the beginning of a flightless form that branched off this line
with the sickle-claw.

>>And that pedal claw, is that considered a synapomorphy with the
>>condition, or did it evolve separately?

>The original herpextensibility of the 2nd toe was the basic synapomorphy,
>you like, that Archaeopteryx shared with all the other funny-toe-2'ed
>merchants; the bigger, non-ambulatory claw is also a synapomorphy between R
>and the droms, in the sense that the droms inherited it from R.

Thats about what I`m thinking, it`s a basic synapomorphy that started with a
Rahonavis-like flying form.


>--Original Message-- From: Larry Febo <larryf@capital.net>To: T. Mike
><tkeese1@gl.umbc.edu>: Thursday, February 25, 1999 01:22 AM


>[On the subject of the cladistic explantion:]

>>Well, I think I`m beginning to understand

>When you start to understand it, that's when you want to start worrying!

I said I was starting to "understand" it, ...didn`t say I liked it ...(or
not). Computers may help sort out all the details, but human subjectiveness,
in determining exactly what are proper symapomorphies to be plugged into the
equation,  I suspect may "predjudice" the truth in some of these cladograms.
I`m suspicious, but will try (at least) to understand it.

PS I may be "old fashioned", but I like to look for ancestors. After all, in
actuality, somewhere along the line....something BEGAT something else!



Larry Febo...visit my website!...see what I think.