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The origin of flight: from the water up - still LONG



> The only hypothesis that does preclude the others is the "FUCHSIA" one,
> since it assumes the development of feathers to the point of being able to
> fly in air (but not doing so!) PRIOR to the maniraptor becoming mostly
> aquatic.

True. But e. g. using the wings also for display, including complex
courtship dances and jumping, is not precluded, I just think this alone
didn't lead to flight.

> After some extended time adapting to living mostly in the water,
> the maniraptor develops the strokes for flight due to the need for them in
> the water,

No, it uses the basic motion of its arms -- the famous predatory stroke --
from the beginning, as waving around its wings is the most effective thing
underwater it can do. And it doesn't live "mostly" in the water, it just
hunts there, like a dipper. It may well derive a considerable amount of its
food from dry land. No specialization necessary.

> then for some reason applies these strokes to flight in the air.

Basically, it flies out of the water as fast as it can, and finds that it
doesn't fall down :-)
(This is indeed the weakest part of the whole argumentation. Nevertheless,
the corresponding parts of other hypotheses are at least as weak. E. g. a
flightless roadrunner analogue will likely stay flightless, given how little
roadrunners fly.)

> The only good thing about this idea (in my opinion, of course), is that it
> posits a reason for the separation between the forelimbs and hind limbs in
> terms of the locomotion cycles.

Hm. Due to bipedality, fore- and hindlimbs were already separate, weren't
they? A more important question is the separation of hindlimbs and tail.
Using the tail for steering, as Archie could have done, might be a good
start. But full separation may well have come only after a considerable
reduction of the tail.

> I don't think the "FUCHSIA" hypothesis explains why the maniraptor would
> need to use its wings to 'fly' in the water,

They are what it has, and they are enough, even though not perfect.

> rather than converting to
> smaller, more penguin-like wings;

It still needs its wings for brooding, and maybe display and whatnot. I
think FUCHSIA went pretty fast, the time to evolve penguin-like wings may
not even have been available.

> After 'learning' how to be good
> water 'flyers', why would you assume the skills would transfer EXACTLY to
> flight in the air?  The only thing that would match would be the stroke.

When more normal wings rather than penguin-like ones are used, the only
thing that would _not_ match is the frequency of the wing strokes (HP Jim
Cunningham, I await your rebuttal :-) ).

> Pulling oneself through the water it NOT the same as pulling oneself
through
> the air (Try it yourself! :-)).

I can't. I'm too big, and I can't find a way to make myself wings of that
sort. The usual wax is much too weak :-)

> The question is whether a sufficiently advanced form of the
> oil glands were developed to allow the aquatic maniraptors to BE aquatic.

Semiaquatic. Anyway, the existence of such glands may well be untestable.

> Personally, I think that "Archie" could fly, probably much better than
your
> average chicken, and maybe nearly as good as a wild turkey.  (This is
based
> on extrapolating from tables in Pat Shipman's book "Taking Wing", and
other
> miscellaneous items).

This excellent book doesn't take Archie's not-asymmetric-enough feathers
into account.

>  Also, its lifestyle may have easily included diving
> down to grab fish or smaller animals and insects from the water.

Do you mean plunge-diving? That may well require more adaptations than seen
in Archie.

>  It may not have been an extremely
> specialized feeder (just a guess).

I fully agree.

> I'm trying to say why I think that the
> "FUCHSIA" hypothesis doesn't explain all that it needs to.

I'm trying to say that it is still the best of all bad hypotheses... :-)