Barbarian asks:
As you learned, it's demonstrably true. Didn't you read any of the evidence I showed you?
Evidence? What evidence? Do you mean the 'evidence' that ostriches running down a slope manage to balance themselves using their wings?
Even on level ground, they use them as airfoils as flying birds do, with the same limb movements.
Yes. They show that the bipedal dinosaurs already had all the elements necessary for flight; birds just adapted what was already there to a new use. Evolution always works that way.
Can you account for the absence of a keel?
Not necessary. Archaeopteryx and Microrapter could fly, and neither had a keel. It's necessary for strong and prolonged flying.
The "keel" is still there in ostriches; it just failed to grow much as the birds got bigger. As you just learned, it's not essential to flight.
Barbarian observes:
As you learned, all the physical and behavioral components necessary for flight were already present before there were birds.
The were useful in other ways for the animals having them.
Nope.
Barbarian observes:
When there were feathered bipedal dinosaurs with full-evolved flight feathers, such as Microraptor.
Why were they there if Microraptor couldn't fly?
It could. The assymetrical flight feathers, found only on flying birds, and the deep insertion of feathers to the bones of the wing pretty much settle that.
I understand it had 4 'wings'.
No, but it did have flight feather on the legs, which seem to have been useful as control surfaces.
Where did the extra 2 come from
Pre-existing things (legs).
Still there in birds. My thought is that such an early flier probably lacked the fine control that birds have today, and the lower feathered surfaces probably served to stabilize flight, much as the tails of early pterosaurs, or tails on kites.
If it was a glider, then how did its non-gliding ancestor obtain the information needed for it to glide?
As you learned, running dinosaurs already used wings as airfoils.
That is evolutionary nonsense, because those genes, being useless, would have been selected out long before flight arose.
As you learned, they were useful in the organisms that preceded birds. Evolution always works like that, adapting old things to new uses.
Barbarian observes:
As you learned, the adaptations didn't appear out of nowhere, but (as always happens in evolution) were merely modifications of something already existing, and useful in its own right.
Sorry, you're question-begging again.
That excuse won't hold up for you. As you learned, the structures and behaviors used in flight were already in place before birds.
But let's pursue that further. You're saying thatsomewhere along the imaginary evolutionary line, something appeared that was useless for flight, but useful for something else. So far so good?
Read it again. Bipedal feathered dinosaurs used their wings as airfoils to control movement. So everything necessary for flight was already there.
And somehow, in the process of time, that something became a feather (BTW, why did reptiles have feathers?
Dinosaurs, at least the smaller running ones, are now known to be warm-blooded. So feathers were likely first useful as insulation, and we know they served as signals (we have found evidence of color and pattern in them)
(And where are the feathered reptiles today?)
Flying around. The only survivors of that clade are birds.
no, 10 different types of feather, wings (proper aerofoils - BTW, what IS an aerofoil? Did you find out?)
In the US, it's called an "airfoil." Learn about it here:
http://en.wikipedia.org/wiki/Airfoil
Quite incidentally, for the benefit of the non-biological among us, did you know that reptiles have possibly the lowest metabolic rate in the animal kingdom,
As you just learned, the small bipedal dinosaurs had high metabolic rates and were warm-blooded. That's why at least some of them had avian lungs. It was necessary for an energetic life style. Velociraptors, for example, ran down and killed larger prey. This while the few mammals about where relatively sluggish with lower metabolic rates. And even modern reptiles generally have more energetic metabolisms than most fish and amphibians.
You've been misled about that.
Can you see the physiological and biochemical problems involved in producing those differences?
Doesn't seem to be much of a problem. Some fish, for example, are warm-blooded. So that, too, is an adaptation. Birds evolved from organisms that already had high metabolic rates.
The whole thing is so stupid I can't understand how someone of reasonable intelligence can possibly believe it.
I think if you spent a bit of time learning about it, you could understand.
Back to topic 
)
