Re: large fossil birds

[Tim Williams <twilliams_alpha@hotmail.com>]

Patrick Norton wrote:

> All bets are off if you push this back into the Mesozoic, however....

If we define 'bird' as any member of the clade Avialae, then I think 
_Dromornis_ is still the 'largest' ground-dwelling bird that ever lived.  As 
you say, in the context of avian dimensions, "largest" could mean 
"heaviest", "tallest" or even "broadest wingspan".  But on all three 
accounts, I don't think we'll find any Mesozoic bird that's heavier than 
_Dromornis_ or has a broader wingspan than _Argentavis_.

The biggest terrestrial bird from the Mesozoic bird is perhaps the 
presumably flightless _Gargantuavis_ or a similar-sized French bird 
(unnamed, but also from the LK), around the size of an ostrich - but there 
may be hesperornithiforms that were bigger (=heavier in this context) - I'm 
not sure.  I don't know what the largest volant Mesozoic bird was, but it 
may be the soaring _Sapeornis_ - but even this was only around the size of a 
gull.  There might have been larger enantiornithines by the LK.

Cheers

Tim