The attitrion of taxonomic expertise

James Lyons-Weiler weiler at ERS.UNR.EDU
Fri Oct 18 09:19:36 CDT 1996


On Fri, 18 Oct 1996, Thomas Pape wrote:

> At 08.31 1996-10-18 -0700, James Lyons-Weiler wrote:
>
> [snip]
> >To identify a character state as a synapomorphic because it is not
> >homoplastic on the tree it helped you choose is entirely circular.
> [snip]
>
> Synapomorphy relates directly to homology. We test homology by congruence or
> 'best fit' in a context of evolutionary parsimony.
>
> How can that be circular?
>
>
> Thomas Pape

The "best fit" part is circular; the data that are used to choose the tree
that provides the best fit are used to test homology (the data).

James



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