Re: Mesozoic - the heyday of life?

[Jonathon Woolf <jwoolf@erinet.com>]

Dinogeorge@aol.com wrote:
> 
> In a message dated 97-06-11 04:51:43 EDT, jwoolf@erinet.com (Jonathon Woolf)
> writes:
> 
> << I might also add that as far as I can tell, the mammals have produced
>  more variety in sixty million years than the dinosaurs did in a hundred
>  and fifty million.  I don't think our furry cousins have anything to
>  feel inferior about at all. >>
> 
> Don't be so sure about this. There is considerable bias in the fossil record
> toward more recent forms (e.g., Cenozoic). As more dinosaur horizons open up,
> more new dinosaur genera are described. And don't forget that modern birds,
> which are dinosaurs as well, are the most diverse tetrapod subgroup, beating
> mammals by more than two to one.

Welllll . . . . I think this kinda depends on how you define
"diversity."  How do you define it?  Is it the same thing as "variety"
(which is the word I used)?  

-- JSW