Page 69 - The Origin of Birds and Flight

Harun Yahya (Adnan Oktar) 67

Most birds have eight air sacs, functioning just like bellows to move air
along their respiratory canal. Many air sacs extend into bones known as
pneumatic bones. (Pneumatic means “working under pressure.”) Thanks
47
to this unique creation, birds’ lungs remain always inflated, unlike those
of mammals and reptiles, always providing them with fresh air. 48

The Avian Lung: One Example of Allah’s Creative Artistry

When a bird inhales, air travels towards the rear air sacs(1). These then propel the air inside
the lung (2), and air then flows from inside the lung to the front sacs (3). When the bird
exhales, the front sacs expel the air. The avian lung does not expand and contract in the same
way that reptile or mammalian lungs do. (In the dia-
gram, blue represents low levels of oxygen and red,
high oxygen content.) The blood that collects oxygen Air cavities in
from the lung travels in the opposite direction from the the bones
flow of air. Thus the blood is carrying the lowest level
of oxygen when exposed to the fresh air.

Air flow Lung
Air sacs

Interior Blood flow
Mouth
of bird Trachea Bronchia
Lung
lung
In every region of the circulato-
ry system, the oxygen content
Front air sacs
(Some of these of the air is higher than that of
are located the blood it makes direct con-
inside the Rear air sacs
tact with, so the efficiency of
bird’s hollow
bones.) Outer bronchi the oxygen exchange from air
to blood is very high. This is
known as counter-current
exchange. Their efficient lungs
enable birds to meet the high
energy demands of flying,
especially at high elevations.
This flawless structure deals a
lethal blow to evolutionist
claims, and is just another one
of the proofs of creation.
Capillary blood Capillary air vessels
vessels