Page 67 - Design in Nature

Sparrows have
The outspread wings of the stork in keeled sternum
that enables them
the figure show the composition of its
various feathers. Shorter feathers to fly for extended
layered one on top of another give the periods. This bone is
covered with breast
bird aerodynamic advantages.
muscles.
RIB CAGE
The breast bones of birds are relatively inflexible for
protection of the body when the wings are closed. That is,
the volume of the rib cage does not change during flight,
inhalation or exhalation.

Shoulder feathers

Wing primaries

Wing secondaries

Wing feathers

Lung

Air sac
"Running birds", such as
the ostrich, have long
legs and strong
Gizzard
muscles that
Crop function in
running,
Heart whereas predator
birds have shortened
bodies and relatively
spinal cord sloped, which
Liver Stomach enables them to move
Bird of prey
more swiftly. Running bird