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Re: *Archaeopteryx* Is Not A Penguin




Jaime A. Headden wrote:

> ...............to alter the ability of passivity?

I'm sorry, I don't know what that means.  Would you elaborate please?

> I understand that penguins reduce their feathers and increase
> their aspect ratio to compensate for their medium, and gain the
> most thrust and "lift," and if the same features were applied in
> the air but correspondingly to body size, the penguin would be
> the most powerful flier.

Again, I'm not sure that I understand.  Are you saying that penguins are
descended from flighted birds that had a lower aspect ratio?  If so, I
don't know - phylogeny isn't my thing.  Re feather surface texture in
penguins, I haven't looked into it.  I was commenting on the possible
effects of feathers on surface texture and boundary layer -- whether
reduced or not.  Re applying the the same features in air, there would
have to be quite a few morphological changes to compensate for the
difference in density and wingspan, and the relationship between power
required and power available would come into play.

Jim