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RE: Campbell's even crazier than a MANIAC? (archeopteryx



Tom Holtz wrote:


> For myself, I think that far too many people extrapolate a neoavian
> (non-tinamou, non-galliform) flight ability too far down within the history
> of birds. Based on flight distribution of living birds, I consider it quite
> likely that good long distance flight may have been limited to anseriforms
> (and not sure how far down it goes among these) and in Neoaves, and that
> basal members of Aves/Neornithes may have had a more limited flight scope.


Also, this part of the tree (basal Neornithes, with Neornithes being the crown 
clade) is crowded with large flightless taxa: ratites, dromornithids, 
diatrymids, brontornithids.  Is this a consequence of chronology (i.e., many 
large-bodied flightless forms emerged soon after the K/T extinction, because of 
the availability of recently vacated niches); or did some innate property of 
basal neornithean anatomy/behavior make them more likely to give up flight 
(such as their level of flight capability).  



Cheers

Tim
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