Re: Dinosaur mass table online

[Tim Williams <tijawi@yahoo.com>]

Zach Armstrong <zach.armstrong64@yahoo.com> wrote:


> Except, of course, when _M. sinocanadorum_ was published,
> mamenchisaurs were thought to be closely related with
> diplodocoids and now, they aren't, but are thought to be
> basal eusauropods (the _M. sinocanadorum_ paper was
> published 1993, whereas a non-diplodocoid, data-set-based
> classification was first given by P. Upchurch in 1995, as
> far as I know).


Actually, the original description of _M. sinocanadorum_ included a 
phylogenetic analysis.  This found that _Mamenchisaurus_ was *not* a 
diplodocoid, but formed a clade with _Omeisaurus_.  OK, so it wasn't the best 
analysis (only 9 taxa, 21 characters); but it's enough to show that Russell and 
Zhang (1993) were not influenced by presumed diplodocoid affinities.  


The main reason why Russell and Zhang (1993) thought _Mamenchisaurus_ was a 
rather slender sauropod was "because so much of its length consisted of an 
extremely long and light neck".  


Cheers

Tim