Archaeopterygid bird from China

John Grehan jgrehan at SCIENCEBUFF.ORG
Thu Mar 31 08:10:27 CST 2005

This response more or less covers similar points made by Ken and

> -----Original Message-----
> From: Taxacom Discussion List [mailto:TAXACOM at LISTSERV.NHM.KU.EDU] On
> Behalf Of Karl Magnacca
> That simply means that the oldest fossils haven't been discovered yet.
> Since we can't ever know that we have the absolute oldest, each one
> is found is empirical evidence and the cumulative weight of that
> determines support for the hypothesis of place of origin.

It's the connection that is being made about the location of the oldest
fossil and the 'place of origin' that's the problem. What underlies the
kind of reasoning by Ken, Richard, and others, is that the 'place of
origin' of a taxon is some smaller area than the current area occupied,
and that this smaller area (center of origin) is determined by the
location of the oldest fossil. I see two problems with this. The first
is that the assumption of a geographically restricted center of origin
is just that - an assumption derived from a theoretical postulate that
begins with Darwin. And Darwin's justification for this theory was not
an empirical proposition, but a demand for adherence to his personal
authority to judge the matter as being one of simplicity that leaves any
alternative view as an appeal to a miracle. Since then most
biogeographers have followed suit (naturally as most biogeographers are
Darwinian evolutionists). The second problem is the assumption that the
oldest fossil has any necessary relationship to the theorized center of
origin. Thus history is replete with evolutionists dancing from one
center of origin to another as ever older fossils are found.

> No, it is evidence because the definition of the origin of a group is
> where the basal member(s) lived.  

That seems to be what I said. If one creates a center of origin and then
define it as the place where the basal member lived then that is what
one has - whether or not such a center of origin ever existed. If an
ancestor differentiates vicariously one of the descendant taxa will be
'basal' relative to others even though its origin was concurrent with
all the more derived taxa so the location of the basal taxon is no more
the 'center' of origin of the group than any of the more derived

So, the place of origin is where you
> will find the oldest fossils.  

As above - if the place of origin exists in the Darwinian sense as a
general evolutionary process.

I think it can
> considered empirical evidence for an origin in China.

You have basically argued the opposite, that the evidence for a
restricted origin is not empirical since the 'empirical evidence' is
derived from non-empirical theorizing that a restricted center of origin
exists in the first place - and that's where I think there is more
fantasy than reality.

John Grehan

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