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



So, agreeing to the ground-up theory, perhaps the most parsimonious thing to 
admit is that birds had wings of scarce use for locomotion (using thier wings 
for brooding or courtship), until they get the muscular mass necessary in their 
pectorals to perform strong flight, without a gliding phase. If they could get 
into trees (WAIR mediating) their flights might have been longer, but the 
non-climbing state in the Paleognathae argues against this.

Indeed, apparently among the most basal Palaeognathae and Neognathae alive 
(tinamous and galliforms) flight is short, and that might be the primitive 
condition (but not in the also basal Anseriformes), and takes origin from the 
soil. Perhaps all the Cretaceous birds were not better flyers than tinamous and 
chickens??.

After all, it is true that based on the recent evidence, flight is more basal 
than gliding for birds (e.g., tinamous and galliforms do not glide, but fly).
 
Now, with respect to retroversion of digit I, perhaps it has not so much to do 
with perching as it might have to do with the generalised great angle between 
all digits. There are fossils where even Archaeopteryx seem to have a 
retroverted digit I, even if it cannot perch. Metatarsal I seems to be rather 
freely attached to the rest, so assessing its position seems difficult to 
assess.

It seems we arborealists have to capitulate to parsimony reconstruction, and 
lack of arboreal adaptations.