Crane
Adaptations: The Neck
Click for labeled photo
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A
whooping crane's neck must be very long so the crane can reach down and
pull up blue crabs from the bottom of marshes without getting its body feathers
soaked.
- Every
bird's and mammal's neck is a tube filled with other tubes that carry
important messages and substances from the head to the body and the
body to the head. The trachea carries the air we breathe from
our mouth and nostrils down to our lungs, and sends carbon dioxide back
up from the lungs to the mouth for exhaling. If you touch the front
of your own neck, you can feel your trachea through the skin; it has
rings of cartilage that keep it open so the moist air passing through
won't make it collapse like a flattened balloon. The trachea is also
where most human and animal sounds are produced. A whooping crane's
trachea is straight along the length of the neck, but coils dramatically
as it reaches the body cavity, inside the sternum. Although we can't
see this on the outside, its huge trachea allows the crane to produce
especially loud, resonating sounds in the way that a tuba can produce
louder, more resonant sounds than those of a tiny trumpet. A whooping
crane's voice can carry over 5 miles -- thanks to its long, coiled trachea.
Hear the unison call,
the guard call, and the
soft brood call to
babies.
- The esophagus
is softer and stretchier than the trachea. It carries food from the
mouth to the stomach, and can stretch enough for the crane to swallow
large blue crabs.
- The head
and body are supported by the vertebrae -- a set of special bones
that each have a hole in the middle, like stacked donuts. The spinal
cord runs through these holes, with nerves that carry messages from
the brain to the rest of the body. (You can feel some of your own vertebrae
by running a finger along the back of your neck.)
- Under
the neck feathers are a very thin layer of skin and a thicker
layer of muscle that moves the neck around. A crane's neck can
reach down to the ground and water to feed, stretch up as high as the
crane can reach for bugling and dancing, and turn all around to look
about and to preen the body's back and underside. The skin and muscles
have to be stretchy, too. A crane's neck needs to be as skinny as possible
so that the crane can easily maneuver it all directions for feeding,
preening, dancing, calling, and watching out for predators.
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