Re: Mesozoic - the heyday of life?

[John Bois <jbois@umd5.umd.edu>]

> DSFPortree@aol.com wrote:
>  
> I'm working on another dinosaur script idea for EARTH & SKY radio - seems to
> me that, in many ways, life on Earth took a downturn after the Mesozoic.
> Animals now are generally smaller. Some would argue they're slower, too. They
> don't have as big and varied an arsenal of weaponry, offensive and defensive,
> as did the dinosaurs.

To Jonathon's comments I would like to add this: 
Big is not necessarily better.  As others (DinoGeorge, specifically) have
noticed, Orders? only stand a chance of staying in the evolutionary game
if they maintain _small_ species among their number.  Being big is
having a ticket to oblivion.  Also, being big can be viewed (whether it is
true or not) as being a pathological adaptation of having to defend a
fixed-site nest.  On land, above some maximum size, gravity causes
problems (such as blood-pressure and bone stress)  
Besides you are favoring certain body parts over others.  Given the choice
between a big femur and a big brain, I would choose the latter.  I can't
think of any body parts (well, maybe one) that I would prefer increased
size in.
Cenozoic rules!