Re: Cost in Aquatic Birds (long)

["David Marjanovic" <david.marjanovic@gmx.at>]

----- Original Message -----
From: "James R. Cunningham" <jrccea@bellsouth.net>
Sent: Thursday, April 11, 2002 8:39 PM

> For those who postulated that archie was an aquatic
> swimmer, have you considered the following?

I did write it may well have habitually swum, but _not_ been aquatic, unless
you consider a dipper aquatic. -- No, I didn't consider it.

> For reasonable thrust efficiency,
> underwater 'flying' requires substantially
> more pronation during the downstroke than flight in air

What exactly is pronation? Rotation in a certain direction? (I've so far
only read this term in connection with the capability vs. not of radius and
ulna to rotate around each other... is it the playing-the-piano position, or
is that supination?)

> If archie were a swimmer, there should probably have been substantial
> adaptations for increased pronation-supination ability at the shoulder,
[...]
> This should require either an advanced supra-coracoideus [...] or an
> equivalent mechanism.  I know the s-c isn't advanced.  Are the
> equivalent modifications present?  If not, it
> might imply that archie wasn't much of a swimmer, if at all.

Interesting... I don't know of such adaptations in Archie, but I don't know
the literature well. Anyway, thank you for bringing up an idea for how to
test at least a part of FUCHSIA. :-)