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Re: Mesozoic birds made insects shrink



Well, the birds and pterosaurs really didn't overlap much in terms of size and 
niche, but it would make sense that even early birds could push similar-sized 
pterosaurs to the edge of extinction, unless the pterosaurs became specialized 
like the Anurognathids. There are fewer and fewer of the little ptero's as the 
Cretaceous progresses and birds establish themselves, which could have happened 
quite early. Look at *Nemicolopterus* for a possible example of this.

----- Original Message -----
From: "Don Ohmes" <d_ohmes@yahoo.com>
To: dinosaur@usc.edu
Sent: Tuesday, June 5, 2012 5:14:02 PM
Subject: Re: Mesozoic birds made insects shrink

On 6/5/2012 3:53 PM, Mike Keesey wrote:

> How well do we understand what the evolution of bats meant for birds?

Have bats pushed birds out of any eco-space since the Eocene?

My impression is that the answer is "no, they seem to have largely 
avoided direct competition" -- so that might be an easy and cheap way to 
answer that.

> There is _no_ evidence at all that birds competitively excluded pterosaurs, 
> for instance.

AFAIK, birds waited until the largest ptero's were long gone to evolve 
to similar sizes, yet there is a very long record of at least bird-ish 
animals co-existing with pteros -- that seems to me like indirect but 
strong evidence further supporting the idea that the old "birds were the 
invasive new-comers that doomed the old guard" scenario is not a good 
fit to the geo-record.