Page 77 - The Origin of Birds and Flight

Most evolutionist scientists still believe that birds evolved from dino-
saurs. One consequence of this widespread view is that they ignore all the
evidence to the contrary.
One example of this is the research by respiratory physiology expert
John Ruben at the Oregon State University in Corvallis. A group under
Ruben’s leadership examined the fossil design of the internal organs of
Sinosauropteryx, a small, 120-million-year-old carnivore, and found that
theropods resembled crocodiles rather than birds. Says Ruben:
I realized that here was the first evidence in the soft tissue that theropods
had the same kind of compartmentalization of lungs, liver, and intestines
that you would find in a crocodile—and not in a bird. 1
Theropods have two main cavities: the chest cavity including the lung,
liver and heart; and the abdominal cavity containing the other organs. As in
the crocodile, these are completely separated from one another by the dia-
phragm. In birds, there is no such separation. The function of this division
in crocodiles is to prevent air leaking between the cavities. When the dia-
phragm muscles contract, they retract the liver and equalize air pressure in
the chest cavity by allowing the bellow-type lungs to fill with air.
Birds have no need of such a divider between the two cavities, because
with the expansion and contraction of their air sacs, the air drawn into their
bodies flows in a single direction down millions of tiny air channels.
At the same time, Ruben also showed that theropods and crocodiles
possessed different hip structures, attached to muscles and which helped
the bellow-type lungs fill with air. As a result of these findings, Ruben states:
It’s pretty solid evidence that theropods could not have had a modern,
high-performance avian-style lung . . . and were stuck with an unmodi-
fied, bellows like lung. 2
In an interview, Ruben stated that the pul-
monary system in birds could
not have evolved from
dinosaurs’ lungs.