Re: Bakker's Brontosaurus and Late Cretaceous populations

[Roberto Takata <rmtakata@gmail.com>]

2005/8/2, Tim Williams <twilliams_alpha@hotmail.com>:
> Like a lot of things, 'lumping' and 'splitting' are often in the 
> eye of the beholder.  Nevertheless there are obvious 
> examples of oversplitting.  In recent years there has been a 
> tendency to consolidate.  The Morrison
> sauropods are a good example: _Cathetosaurus_, 
>_Ultrasaurus_, _Supersaurus_,

Well, since supraspecific taxons are artificial anyway, I don't mind
if a species is asigned to one or another genus.

In my view, the real problem on lumping/splitting is when we assign
specimens to the same or different species. As it was the case with
_Triceratops_: are there 7 species or there is just 1? (Unfortunnately
we - as far as I know - cannot perform lab cross experiments with
fossils. Yes, we could do morphometric analysis: but when we have a
discrepancy, is it due to interspecific differences or due to
interpopulational differences - if not a sexual dimorphism ou
intrapopulational polymorphism -?)

[]s,

Roberto Takata