Re: New alvarezsaurid

[Dinogeorge <Dinogeorge@aol.com>]

In a message dated 98-03-25 02:59:58 EST, jaemei@hotmail.com writes:

<< What we have here is a lot of "avian" groups producing one, two, or 
 several characters thought to be distinctly bird-ish. BCF would say this 
 supports their case, and indeed it does, but what if it means that while 
 all these groups were playing with the various characters but not 
 getting the right number of them to turn them POOF! into birds, as per 
 Fedducia? Yes, they could do that, and more. One line, not so bird-like, 
 such as avetheropods (as opposed to maniraptorans) such as 
 oviraptorosaurs, who have a variety of characters unique to birds, 
 including the palate structure, who are morphologically similar to 
 alvarezsaurids like *Mononykus*, *Patagopteryx*, or *Shuvuuia*, who all 
 have avian characters in the sternum and skull. And these in turn could 
 give rise to smaller, longer-armed creatures who continued to reduce the 
 tail and eventually formed a pygostyle, and the skull, of course, needed 
 to change only slightly. So, BADD has its merits. >>

Imagine the arboreal, flying ancestral forms as having most if not all of the
different avian characters that have been noted in "theropods," then >losing<
some of them--randomly (particularly forelimb/pectoral characters, as the
wings vestigialize)--in each different lineage of their ground-dwelling
descendants. It would create a bunch of lineages, each sporting its own
distinct random selection of avian features, some modified from subsequent
evolution, some not so modified. This is what is seen in the fossil record of
"theropods."