Re: Suuwassea (was Re: New Sauropod)

["David Marjanovic" <david.marjanovic@gmx.at>]

----- Original Message -----
From: "Nick Pharris" <npharris@umich.edu>
Sent: Thursday, May 06, 2004 8:35 PM

> For those who are curious, the genus name
> _Suuwassea_ is derived from *suuwassa*,

...and the extra e seems to be there to produce a classic -ia ending. Quite
confusing.

> The paper also names a new higher-level taxon, Flagellicaudata
('whip-tailed
> ones').  The authors define Flagellicaudata as "[a] node-based taxon
consisting
> of the most recent common ancestor of _Dicraeosaurus_ and _Diplodocus_ and
all
> of its descendants".  However, it is apparent that they actually mean
"...the
> most recent common ancestor of _Dicraeosaurus_, _Diplodocus_, and
> _Suuwassea_...", since they refer to _S._ as a member of Flagellicaudata,
even
> though their phylogenetic analysis cannot exclude the possibility that
_S._ is
> the sister to Diplodocidae + Dicraeosauridae.

I'd say that, for the purposes of their paper, they simply take the
trichotomy they get for granted; if it is a _real_ trichotomy, then *S.*
_is_ a member of Flagellicaudata as defined.

(While improbable in this case, true polytomies certainly exist. Many extant
Mediterranean lizard species belonging to *Podarcis* probably did originate
simultaneously from one ancestral species when the dry Mediterranean got
flooded again in the late Miocene.)