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Gregory S. Paul on Confuciusornis



In the new Science out this afternoon:

Comment on âNarrow Primary Feather
Rachises in Confuciusornis and
Archaeopteryx Suggest Poor
Flight Abilityâ
DOI: 10.1126/science.1192963
Science 330, 320-b (2010);
http://www.sciencemag.org/cgi/content/full/330/6002/320-b

I had two questions about Paul's text.

1) "Nudds and Dyke (Reports, 14 May 2010, p. 887) reported that the primary 
features of the early birds Archaeopteryx and Confuciusornis were too weak to 
power flight"

What are these "primary features" that Paul describes? How do these features 
confer weakness on the animals in question?

2) "the shallow-bodied basal bird was intermediate in mass to the 
Munich Archaeopteryx and the deep-bodied pigeon, so the feathers were a number 
of times stronger than calculated by Nudds and Dyke (Fig. 1, A to C)."

How does changing the mass make the feathers stronger or weaker? Isn't strength 
an inherent quality that depends on the structure of the feather?