Re: Segregated vs age-mixed sauropod herds

[Mike Keesey <keesey@gmail.com>]

On Mar 15, 2010, at 11:57 PM, Tim Williams <tijawi@yahoo.com> wrote:


> The same study estimated that the monotreme line (stem-group - would  
> that be 'Prototheria'??) diverged from the Theria in the Early  
> Jurassic.

Total group (or total clade), not stem group. "Prototheria" is the  
name for it (or "pan-Monotremata"). The stem group would be the non- 
monotreme prototheres ("stem-monotremes").

Isn't Mammalia (crown group) usually thought to have originated in the  
Triassic?

--
Mike Keesey