Re: Segregated vs age-mixed sauropod herds

["T. Michael Keesey" <keesey@gmail.com>]

On Mon, Mar 15, 2010 at 5:36 PM, John Bois <mjohn.bois@gmail.com> wrote:
>
> I am thinking of very broad trends: animal body plans and strategies
> evolving most recently indicate higher parental investment: placentals
> compared to monotremes;

Isn't it quite possible that Monotremata and Placentalia (crown
clades) are around the same age?

> birds compared to basal dinosaurs;

What do we know about parental care in basal dinosaurs? (By "basal"
I'm assuming something like "pre-Late Jurassic"?)

> archosaurs compared to lizards.

Aren't the earliest squamate fossils Jurassic?

-- 
T. Michael Keesey
Technical Consultant and Developer, Internet Technologies
Glendale, California
http://tmkeesey.net/