Re: FUCHSIA and the Ostrom Symposium Volume (long...)

["James R. Cunningham" <jrccea@bellsouth.net>]

David Marjanovic wrote:

> + Shows that once wings and musculature sufficient for powered flight are
> present, takeoff from the ground is feasible, so if these features were
> present before flight, as FUCHSIA incl. HOBHY assumes, an arboreal phase is
> not needed.

For birds an pterosaurs, it would appear that takeoff from the ground is
feasible even before wings and musculature are sufficient for powered flight. I
don't have much of an opinion about bats in that regard.

> (+ Explains what well-curved claws are good for in a terrestrial runner that
> doesn't climb -- to retain a grip on the ground when that unwanted byproduct
> called lift becomes too strong.)

I've got some doubts about that, but they are good for retaining a grip on the
ground while turning at speed, or while leaping whether running or not.

> + Shows that sustained flight (cursorial, FUCHSIA) and nonsustained flight
> (parachuting, gliding) can't have both been used while powered flight
> originated.

I don't see the two as mutually exclusive, though I don't see gliding
improvements leading toward flapping improvements, while I can see the
possibility of improvements going in the other direction.

> - Fails to show (actually doesn't even attempt) why a sane winged runner
> would suddenly begin to flap its wings at maximum speed. Why would anyone do
> that, without knowing a priori that doing so increases speed and/or leads to
> takeoff?

It generally doesn't lead to an increase in speed (remember my car and rope
scenario).  It does have other extreme and obvious benefits for a running
animal.  Also, don't forget that cursorial animals are also likely to have leg
power enough to get into the air by leaping without being obligated to do it by
running.

> Roadrunners don't do it when they just run. Chickens are, if I
> don't misinterpret it, mentioned as doing so, but I think they're just
> trying to take off.

I remember the chickens on the farm where I grew up using flapping to help them
turn, to great effect, particularly when I was chasing them.  I don't think we
owned any chickens that couldn't take off when they wanted to.  We naturally
selected those.  They were tasty too.

Dunno about roadrunners.  Do they turn much when they are running, or just go
like h*** in a straight line?

> , and the first takeoffs into the air would have been simply flying out of the
> water.

Sounds to me like taking something simple if done from solid ground and making
it difficult to the point of improbability.

> Jeremy M. V. Rayner: On the origin and evolution of flapping flight
> aerodynamics in birds, 363 -- 385
>
> (- Uses great confidence in an outdated phylogeny to show that bats must
> have begun as gliders.)

Don't forget that Jeremy has forgotten more about flight than most of us will
ever know, and remembers far more than he has forgotten.

> Why shouldn't Archie have had a deltoideus? And when nonavian underwater
> fliers don't have a supracoracoideus, why should *Archie*, more basal than
> any bird with a well-developed supracoracoideus, have had one?

I believe Archie did have one, though not particularly well-developed.  But that
isn't my field -- anybody know for sure?

>  A runner that, in the style of Burgers & Padian above,
> tried to flap wings in the predatory stroke while running would have a very
> effective brake. :-)

Would you explain the mechanics of that to me?  As phrased, I don't understand
why you hold this view.