[Taxacom] sloppy cladistic analyses

[John Grehan]

> -----Original Message-----
> From: taxacom-bounces at mailman.nhm.ku.edu [mailto:taxacom-
> bounces at mailman.nhm.ku.edu] On Behalf Of Kenneth Kinman
> Sent: Wednesday, February 03, 2010 10:39 PM
> To: taxacom at mailman.nhm.ku.edu
> Subject: [Taxacom] sloppy cladistic analyses
> 
> Dear All,
>      Stephen is correct in my opinion.  The narrative which attempts
to
> explore intermediate steps in the evolutionary process can be largely
> lost in the labyrinths of large datasets (which may not be all that
> accurate anyway if workers are taking "shortcuts" and/or don't fully
> understand or attempt to fully evalutate the datasets they have
> inherited from others).  It's even worse for fossil taxa which are
> constrained by very limited data from the get-go.  No molecular data
at
> all to challenge them.

But the problems described above also apply to molecular data where it
is not even possible to provide a homology narrative for each individual
base because no one can ever really know its individual history (other
than as a result of how it fits with the selected phylogeny) and worse,
aligned homologies have no empirical reality. However, insofar as
morphological studies are concerned the above comments are on the mark.
Some of the best examples of extremely bad practice are seen in hominid
studies.

John Grehan