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Re: Archaeopteryx not the first bird, is the earliest known (powered) flying dinosaur
The basic contention that small theropods must have had a lot of
preadaptations on hand before becoming fliers is fundamentally absurd.
to Ornitholestes already has the basic skeletal features needed to become an
incipient glider. All it has to do is evolved sufficiently long wing,
asymmetrical wing feathers, hold the arms out to the sides and there you go.
other stuff for folding the wings (elbow-wrist push-pulley system), further
increasing lift area (longer arms and still bigger wing feathers) and
power stroke (large sternal plate, bigger pectoral crest, ossified sternal
ribs and uncinates) can be developed as flight progresses. No one has ever
why any dinosaurian flight adaptation had to evolve first as a preadaptation,
aside from the combination of long arms and bipedalism. One or more flight
feature may have started as a preadaptation, but that does not mean any or all
Nor has anyone explained why Archaeopteryx has expanded muscle attachments
areas on its arms just to glide. Where is the expansion of muscle attachments
the limbs of any gliding animal? They just stretch out the legs and hold them
there for the brief time needed to make a glide. It is obvious that expansion
of muscle attachments on a forewing will one way or another allow and improve
the power of a flight stroke.
I truly do not even begin to understand the arguments to the contrary. They
seem part of a continuing effort to some, based on a historical heritage that
saw dinosaurs as having nothing to do with birds, to keep theropods that were
not full birds as nonfliers or mere gliders, as though nonavian dinosaurs were
for some reason not allowed to be true fliers. Very odd.
There was no need for sinornithosaurs to deploy the nonflapping leg wings
when power flying. As I discussed in Prehistoric Times a few years ago, they
could have been used to increase the range of periodic nonpowered glides, for
soaring, and has extra flight controls, especially flight brakes, among aerial
ers that lacked the more sophisticated flight apparatus of real raptors.