DDeden Wrote:
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> Ok, I meant "swoop" as a (diagonal-vertical)
> gliding pounce functioning as a stunning action on
> the prey, (not catching it), with no altitudinal
> lift-flying. The alula (thumb-claw-winglet) act to
> stop flight for landing on branches, nests and
> prey, not necessary for near-ground pouncing.

Your explanation helps, but still not good evidence for "gliding pounce" either.

> I didn't say flight,

You used the word swoop and owl as one of the models...that suggests flight.

> and wouldn't expect Zs to
> have proper flight feathers, just
> 'parachute-glide' wings and feathers.

Flying squirrels, for example, fit that description and they don't pounce on victims.

> The perching claw may have allowed climbing up
> unbranched palm trees or tree ferns.

See types for different birds here, note toe lengths:
[lansingwbu.blogspot.com]
Zs doesn't have a perching claw or a pounce claw. Those have equal, longer, or stronger claws. Perch is not the best fit for the claw on Zs, in fact it is the worst fit scenario as the length ratio to the other toes is nowhere near an owl's.

> Here at Miami Beach I see guys climb coconut
> palms, some use side-heel vertical spikes(like
> telephone linemen) jabbed downward, some use
> horizontal toe-spikes jabbed forward into the
> trunk. Notably, the guys are about the same weight
> and size as Zs;
> while lighter-smaller guys tend to
> just clamber up the stem with bare feet/hands.

Yes, actual hands. Those guys also have hands with 4 fingers and a thumb, not so for Zs. Its feathered wings would actually hamper tree climbing by getting in the way rather than being good for climbing. Try putting Zs feathered wings, in place of arms and hands, on those linemen and see if they can still climb a telephone pole or a palm tree.

> Zs was a dinobird of the dense forest, that
> perched above the ground to see prey and pounce on
> it IMO.

We know for a fact dense forests do not preserve fossils very well, that's why there are so few chimp fossils known. The rock matrix Zs was found in is proof it was operating along a shoreline of some sort. That perching claw is actually closer in length and size to a wading bird's claw remnant than that of an owl. It isn't even close, only about 25 % of the length compared to other toes (hard to measure exactly from the photos). But owls (and hawks/eagles) are equal in length, you can see that with your eye. This is evidence it was not a "dinobird" IMO.

> Owls have powered flight and highly evolved flight
> feathers, as do all raptors.

And just the opposite of Zs when comparing foot structure. You are using owls again, that suggests flight and you claimed above "I didn't say flight", yet you keep using a known flyer as model and Zs doesn't have toes anything like the toes of an owl, so there is no reason to suspect flight or perching either.