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Re: MULTIPLE INCLUSIVE ANCHORS?



On Wed, 13 Feb 2002 NJPharris@aol.com wrote:

> In a message dated 2/13/02 3:18:06 PM Eastern Standard Time,
> Tetanurae@aol.com writes:
>
> > Plus many other
> >   stem based taxa with more than one inclusive anchor.  I thought that this
> >  could not be possible, because a topology like this [which is technically
> >  possible, we don't have the hindsight of the creator of the universe]:
> >
> >  --+--Gallus
> >    `--+--Anser
> >       `--Fringilla
> >
> >  would indicate that this supposed stem based clade  is actually composed
> of
> >  two different stems that are serial outgroups to Fringilla, and
> polyphyletic.
>
> I like it.  If _Anser_ should prove to be closer to _Fringilla_ than to
> _Gallus_, then Galloanserae (or whatever clade was being defined here)
> self-destructs, and we don't have to deal with it any more, which is a good
> thing, since the clade was named specifically to encompass a group including
> galliforms and anseriforms but specifically _not_ higher land birds,
> including _Fringilla_.

There is one other solution. Use these definitions, in this order:

_Galliformes_ = Clade(_Gallus_ <-- _Anser_, _Passer_)
_Anseriformes_ = Clade(_Anser_ <-- _Gallus_, _Passer_)
_Galloanserae_ = Clade(_Gallus_ <-- _Passer_)

Thus, if the topology turns out to be (_Gallus_, (_Anser_, _Passer_)) or
(_Anser, (_Gallus_, _Passer_)), _Galloanserae_ becomes a junior
heterodefinitional synonym of _Galliformes_.

Of course, the end result is pretty much the same, so I don't know if it
matters much. (BTW, stick a "Pan-" on all of those if you want to follow
the philosophy in Gauthier & De Queiroz 2001).

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