(My editing time expired so here in full, I'm unable to delete the 2 partial posts preceding this one. DD)
Lee Olsen Wrote:
-------------------------------------------------------
> DDeden Wrote:
> --------------------------------------------------
> -----
> > Sorry, I've been referencing the extra large
> front
> > claw as the perching claw, NOT the
> rear-facing
> > claw! The rear claw was used in balancing
> upright
> > while on the ground, in water, on branches.
>
> So I take it you don't have any examples of a
> perching bird (on the large end of the size scale)
> that can climb with this front facing claw like a
> lineman?
I have no significant evidence that Zs climbed or perched using the enlarged front claw/toe (one each limb, so 4 total, compare this number to (dense forest) 2 toed sloth's claws...no, I'm not claiming that Zs hung upside down from branches...).
I would not expect Neorniths to have this arrangement since they evolved along a different pathway, hollow bones, beaks/bills, many air sacs, arboreal nesting, etc.
> I don't see any here:
>
>
> I'm going with KK on this one: "That big claw
> seems to have been used for deadlier things than
> perching."
Yes, of course. But I prefer it over "Slashing Claw" which I reject entirely.
Cats have retractable claws, but cheetahs don't and like dogs don't climb trees. Do you think Zs climbed trees or chased prey?
The rear one then, seems too small for
> anything on Zs, much less for balancing.
No, it complemented the front perching claw IMO, giving adequate control for perching upright, the combined talons compressing for a good hold, but not enough for sleep due to the lack of a locking tendon arrangement.
After the
> math comes testing a hypothesis in the real world.
> Birds that attack from the air have perching type
> feet, but much stronger, same configuration as
> perching though.
>
Yes, some modern birds are extraordinary attackers from above, I'd guess better than any other flyer.
> > Scavengers are predators in other
> circumstances.
>
>
> My bet is this buzzard, with a similar foot type
> (notice that long protruding front facing middle
> toe?), can't climb like a lineman with it.
I see turkey vultures every day along the Atlantic shores soaring on the breeze, never seen them climb trees, usually they are on the ground beneath the mangrove forest edge. They're pretty lightweight considering their size in flight at least compared to turkeys which they resemble.
Remember I referred to it (Zs's) as a perching claw. My claim extends only that far. Also, Zs had 4 of them, a buzzard has 2, with its wing claws tiny in comparison.
>
> > At least one reason for direct killing might
> be
> > fresh blood in live prey (eg. mosquitoes are
> > parasitical flying predators). Better field
> of
> > view from above.
>
> Yeah, but the mosquitoes don't have a foot pattern
> like Zs and buzzards.
They perch on 4 or 6 legs, right?
>
> > Humans pick up needle between the thumb and
> > forefinger. Chimps pick up a needle between
> the
> > forefinger and the index finger. Zs was not
> a
> > modern bird. Modern birds perch with a
> rear-facing
> > toe/talon. Zs did not.
>
> You have yet to demonstrate how any bird, modern
> or not could climb at all with the Zs/buzzard
> pattern.
Again, I called it a perching claw. Climbing with the use of 4 perching claws and opposing rear claws to clasp branches/bark does not seem improbable to me.
> >
> > Do you think that you can perch (for an
> instant
> > only, due to lack of practice) by putting the
> big
> > toes down and the other toes curved over a
> branch,
> > and grasping? I've done it, and written my
> > signature using the same grasp (barely
> legible but
> > nonetheless). Again, with the big toes down.
>
>
> I'm not sure what you mean. Olympic tumblers can
> balance on a beam, but I don't see how that can be
> called perching.
They wear slippers. I meant bare foot, perching. But that's another train of thought, not closely connected to the topic, so I'll drop it.
>
> > I did not refer to Zs's perching claw as a
> > pouncing claw,
>
> You used an owl for a model, that has a perching
> claw and a grasping claw that does double duty,
> front and rear. We need an example of same in the
> real world that has an oversized front facing claw
> that can climb with it, like a lineman.
Well maybe there is one in a dense forest somewhere, but probably not in open water wading or open plains running.
>
> > and certainly not a slashing claw
> > (as I've seen written in the literature).
>
> Since Zs has a head and teeth like a T-rex, I'm
> sure it would need something substantial to hold
> the victim while tearing it apart with it's teeth.
> So yeah, maybe the claw wasn't used for slashing
> per se.
Right. Pouncing would stun prey, struggles would be reduced, body weight would probably hold prey long enough for a killing bite.
>
>
> > I agree sparrows don't always pounce on
> their
> > prey.
> >
> > Woodpeckers bore with their beaks.
>
> But climb with feet up vertical poles with their
> toes.
Yes, with some support from their (woodpeckers) stiff tail feathers I think. Did Zs have a stiff tail you think? The reconstructed image shows a sort of ladder-like feather arrangement along the spine, if they were stiff bristles they might have helped vertical climbing, as some reptiles do. Perhaps tactile prehensile tails originate this way in opossums, macaques, capuchins etc.? Please see both reconstruction images, the fossil tail looks straight and stiff. Wonder why. It didn't have a few long straight feathers sprouting from the base like a peacock, but had bunches all the way to the tip.
>
> > Linemen use a belt, freeing their hands for
> work
> > while they are perched vertically. Zs had 4
> > perching claws, 2 in back (=spurs), 2 in
> front
> > (=belt).
>
> The linemen I've watched place the belt around the
> pole before taking the first step (or spur dig in)
> and then with both hands flip the belt upwards as
> they go, using the belt to hold them from falling
> as they unhook with a spur for the next step.
> Definitely used to climb with.
Yes. I've done that up a coconut palm, with no spurs, just bare feet. A bit rough descending.
> These guys are using a rope, but same principle.
> They don't have a heavy bag of tools to worry
> about, so a rope works for racing I guess.
Yeah, or a sarong around the ankles pinching the trunk allows fast climbing without spurs, as in SEAsia/Polynesia.
>
> > I agree that Zs may have been moving towards
> a
> > larger body size, but not sure.
>
> T-rex is just a model. Take a look at these
> creatures:
Yes, all those may have been similar to Zs in perching/pouncing (including cliffside attacks too in some areas).