Re: Titanosaurs

[Stanley Friesen <sarima@ix.netcom.com>]

At 11:58 PM 12/12/97 PST, Jaime Headden wrote:
>like diplodocids than they do the one skull belonging to 
>*Antarctosaurus*. The skull of *Argentinosaurus*, ...

Oops, forgot about those.
>
>o = ancestrous cetiosaur
>|
>*Shunosaurus*
>|
>*Euhelopus* and kin
>|               | |
>Macronaria      | *Mamenchisaurus*
>|               |               |
>Camarasaurids   Titanosaurids   Diplodocids
>&               &               &
>Brachiosaurids  Saltasaurines   Dicraeosaurids
>
>If this clade is acurate, or close to the truth, than titanosaurs are 
>basal diplodocids stemming from advanced "euhelopodids",

This cladogram has one problem: Euhelopus and Mamenchisaurus have 17
cervicals, and the others all have 10-12 cervicals.  Combined with other
factors, I think this makes a *clade* containing both _Euhelopus_ and
_Mamenchisaurus_ at least a decent possibility.

It certainly makes _Euhelopus_ and unlikely ancestor for the
camarasaurid/brachiosaurid clade, and _Memenchisaurus_ and unlikely
ancestor for the diplodocid clade.

--------------
May the peace of God be with you.         sarima@ix.netcom.com
                                          sfriesen@netlock.com