Answer 1:
Owls are very interesting animals. In general,
their eyes are like ours. Here's how they work.
Light comes into the pupil of the eye and is
picked up by receptors at the back of the eye.
Some complicated things happen, and then nerves
carry information about the light to our brains.
The brain makes sense of the information and we
see an image.
Let's go back to those
receptors. There are two major kinds and we have
both. Rods only let us see black and white, but
they work really well even if the light is very
dim. Cones let us see color, but only work well
when it's pretty light. You may have noticed that
if you look at things when it's sort of dark, you
only see shades of black and gray.
Owls
have good night vision for a few reasons. First,
they have a lot more rods and not as many cones,
so they lose color vision, but see a lot better at
night. Also their eyes are very large,
so they
pick up a lot of light rays.
Owls have a
sort of mirror at the back of their eye called the
tapetum lucidum. When light goes past the rods
and hits the mirror, the light is reflected back
at the rods. This means the owl gets 2 chances at
catching each bit of light. When you shine a light
at an animal at night and their eyes seem to glow,
you know they have a tapetum lucidum. You might
be wondering why we don't have this, since it
seems so useful. The drawback is that it makes
what you see slightly blurry, so animals that are
active in the daytime don't have them.
There are some owls that are active during
the day. Do you think that they have the same
kind of eyes as owls that are active at
night?
Thanks for asking, |