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Shoehorning (Augury and Alvarezsauria)




The point is that "Alvarezsauria" should probably have never been proposed to begin with. I regard it was a form of *shoehorning* to group genus Alvarezsaurus with mononykiforms.
More recently Sinovenator was shoehorned into Family Troodontidae. So what were once call troodontids were soon being referred to as "derived troodontids". I don't think this is a good practice, and when it affects formal nomenclature, it just adds to the confusion once the premature assignment is overturned.
I don't pull phylogenies out of thin air or read entrails. I'm just as interested in discovering correct phylogenetic topologies as anyone else, but I've seen strict parsimony lead too many workers astray to put too much faith in it. Just because my approach can't be reduced to an algorithm doesn't mean I'm just making stuff up. If the "current evidence" for a grouping looks like a bunch of homoplasies to me, then I consider that a lack of evidence. Giving plesion status to Sinovenator or Alvarezsaurus makes more sense to me than prematurely shoehorning them in where they probably don't belong.
------ Ken
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Tim Williams wrote:


Ken Kinman wrote:

> As I stated back in February, I no longer have much confidence that either "enigmosauria" or "Alvarezsauria" (incl. mononykiforms) is paraphyletic (much less holophyletic). I would give it a 30% chance that one is paraphyletic and the other polyphyletic, and a 50% chance that *both* of them are polyphyletic. I will still give it a 19% chance that both are paraphyletic, but only a 1% chance that both are holophyletic.

And there's a 100% chance that the above paragraph is absolutely meaningless.

If you were to do a vox-pop poll of paleontologists, I'm sure the majority
would agree that Alvarezsauridae might one day be shown *not* be a natural
grouping (i.e. monophyletic or 'holophyletic' in your usage). But you see, the *current* evidence (which, when you think about it, is all we have to
base analyses on) currently points to a monophyletic group comprising
_Alvarezsaurus_, _Patagonykus_ and Mononykinae.


Perhaps future discoveries will undermine this interpretation - who knows?
I know Ken likes to cast himself as the "Cassandra of Phylogeny" - fated to
be correct, but never believed until after a prediction comes true.
However, to say that a clade *might* be split up as the result of future
discoveries is nothing more than platitude.  Every study allows for this
possibility; but pulling new phylogenies out of thin air has no more
credibility than talking to serpents or the reading of entrails.



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