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Re: Feduccia's allegations and logical arguments



----- Original Message -----
From: "Philidor" <philidor11@snet.net>
Sent: Sunday, January 26, 2003 3:58 PM

> Put another way, a supposedly primitive condition cannot be strongly
> identified by looking at the conditions in subsequent versions.  Traits
can
> arise in too many different ways and for too many different reasons to
> identify them indisputably as continuations from an unknown previous
> version.

Right.

> My guess is that this problem is the reason why some versions of
cladistics
> overlook time as a factor, substituting logical rules about what must be
the
> ancestral condition.

A few people include time in their matrices. Don't know what that looks
like, but probably like "lives in the (0) Jurassic, (1) Cretaceous". Most
workers dislike this, pointing out how incomplete the fossil record is,
and/or are practically proud of ignoring time -- phylogeny first, scenario
second. Not a bad idea IMHO. In Chapter 1 of Mesozoic Birds, Witmer
elaborates this as an argument against the "temporal paradox".
    What the ancestral condition for a certain clade is is read out of the
cladogram, after the analysis has been completed. Again: phylogeny first,
scenario second. :-)

> My own view, for what it's worth, is that the available evidence supports
> the dinosaurian ancestry of birds while little supports an alternative.

Er... *Microraptor*, let alone *M. gui*, isn't needed for this. -- What
alternative? Crocodylomorphs aren't supported any longer by anyone, it
seems, neither is *Euparkeria* (there was a paper in 1995 which identified
features it shares "only" with birds), and after these, nothing has been
formulated. It isn't clear if the BAND's "avimorph thecodonts", or one of
them, are meant to be ancestors or just what an ancestor may have looked
like -- sistergroups are never mentioned --, no lists of features are
published, and so on.

Very interesting that Feduccia now accepts (or almost accepts)
oviraptorosaurs and dromaeosaurs as birds. Soon he'll have all Avepectora as
Aves. I bet a cookie that next year he will proclaim *Tyrannosaurus rex* as
the biggest bird ever... :-) (though not based on its bird teeth, I hope).

> The preponderance of evidence thus supports accepting the dino-to-bird
> hypothesis, though recognizing that a single new fossil from the right
time
> could eliminate that preponderance.

May tell more about me, but I can't imagine such a fossil. Can you?