Page 120 - Miracle in the Eye

M MIRACLE IN THE EYE

Double Vision
On most species of snakes, the eyes are placed on either side of the
head, which produces two different images in the snake's brain. However,
this location of the eyes doesn't stop the snake from seeing forward. In fact,
this positioning gives the snake a wide visual perspective, allowing it to look
forwards, backwards and upwards with ease.

Infrared Vision
As you've seen, the human
eye can perceive only a specific
range of wavelengths of light.
Some species of snake are capable
of seeing greater wavelengths
than humans, including infrared
light, which humans can sense
only as heat.
Snakes have small pit organs
that can visually register infrared
radiation. These organs are a hun-
dred thousand times more sensi-
tive to infrared than human skin
and can detect even the slightest
change in a body's temperature.
For example, the rattlesnake
can locate a warm-blooded animal
or human even in pitch darkness,
because such creatures radiate off heat waves that the snake can detect—an
incredible advantage for any creature hunting at night.
The principle of detecting objects and soldiers by the heat they emit is
also used in recent optical military equipment. It took years of research to
develop the technology behind this kind of equipment, but snakes enjoy the
same ability from the moment they hatch from their eggs. It took decades for
humans to develop heat-sensing equipment, but snakes have always had it.

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