Cladistics and Eclecticism

[SKÁLA Zdenek]

Z Skala:
>>What we really do in cladogram construction is summarizing the "amount of
>>character change" (i.e. the largest clusters of mutually compatible
>>synapomorphies) to construct/recognize "real" clades. 

T DiBenedetto:
>... the focused goal is arrive at a deeper
>understanding of characters - which similar character states are...homologies, 
>and which ... convergence.

This is exactly what I had in mind (writing in operational terms, though) so no disagreement here.

Zdenek:
>Eclecticists ... use these clusters of
>synapomorphies also for the splitting of the cladogram. 

Tom:
>Yeah, but that destroys the ability of the cladogram splits to represent the
>history of lineage splits.
Well, you have probably in mind that the hierarchy of *taxa* does not represent the hierarchy of cladogram splits. That is true.

Tom:
>In other words, that defeats the whole purpose of
>using systematics in the pursuit of understanding the history of life.
No, it does not. Only if you are defining the right history representation in the sense of holophyly ("including all descendants") you can speak about misrepresentation of history. Eclecticists evidently define right history representation otherwise (having a common ancestor) and hence represent the history correctly. Hence, again, this is a matter of definition what is "true representation" and the discussion could easily become tautological.

Tom DiBenedetto:
>OK, I think we agree. So long as we recognize all clades as taxa, we are not
>as arbitrary as ecleticists, - is that what you are saying? I can agree with
>this.

Yes, exactly. Note only that taxon=named taxon (not only a possibly named one - see also Comments by Susanne Schulmeister). Nice that we can agree.

Zdenek Skala