Re: postulated bird/pterosaur competition... with a little HUMOR (?) at the end :o)

["philidor11" <philidor11@snet.net>]

Sorry to be coming on this so late, but I wanted to clarify an apparent
contradiction:
HP Cunningham commented:
<During that period [later Cretaceous], the big pterosaurs were larger than
any birds have ever been, or are likely to ever be because of structural
limitations that affect bird
wingspan more than pterosaurs.>
and later:
<I think the larger pterosaurs also may have helped keep birds from becoming
larger (sort of the inverse of John's view).>
Are these mutually exclusive alternatives?  Might the inability to compete
with the larger pterosaurs have caused birds to specialize in a way that
formed the structural limitations?
Just curious.