[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]
Re: NEW PAPERS and flight stroke
----- Original Message -----
From: "Williams, Tim" <TiJaWi@agron.iastate.edu>
Sent: Tuesday, May 14, 2002 7:05 PM
> Alas, the thylacine remains Austalia's most common extinct animal.
> The presence of feathers on the distal forelimb (the primordial
> primaries and secondaries) and tail of _Archaeopteryx_ has been by Garner
> al. (1999) to argue that the initial purpose of flight feathers (remiges
> rectrices) was to generate drag, not lift, during steering motions - the
> enlarged feathers could generate the most drag (and later thrust) when
> placed far from the body.
If flight feathers evolved for some activity in air, that is. -- About
flight (rather than flight feathers), I just saw a Pacific relative of
*Fratercula arctica* on TV (Alastair Fothergill's Discovery Channel ocean
series, last part, about coasts); it was flying slowly underwater. It has
pretty long and narrow wings... I'm pretty sure broader wings, like
*Archaeopteryx* has them, would be more effective for the way it did it
(would, if stiff enough, generate more thrust; shorter wings would give more
manoeuverability). Tertials seem to be unimportant because the wings are
half folded. Cries for a biomechanical test IMHO... maybe I'll build the
models sometime :-)
Such slow locomotion would probably make it very difficult to get
out of the water and fly on in the air, though.
Blood is quite a special juice.
Every Juice has two sides.