Sight is only one of the five senses which functions as a way to see not only colors and shapes, but can tell if objects are near or far away. Eyes can see movement and distinguish familiar patterns. Small, but impressive organs, eyes allow the wonders of sight.

Gee Whiz Facts About Eyes

Eyes in Different Places

Animals like the wolf and the lion have eyes on the front of their heads; the giraffe and rabbit have eyes on the sides of their heads. Animals who hunt like the lion have both eyes facing forward which gives them the ability to see farther and judge distances more accurately. Animals that are hunted, like the giraffe, have eyes on the sides of their heads so they can see all around them.

My What Big Eyes You Have!

Nocturnal animals like the owl, galago and the domestic cat have very large eyes to let in lots of light so they can see at night. Owls have eyes on the front of the head for greater depth perception. Owls and other birds of prey have eyes that enable them to see with amazing accuracy while flying high above the ground searching for food. In dim light, owls see 10 to 100 times better than humans. The domestic cat, like many nocturnal animals, have developed an adaptive layer, called the tapetum which acts as a reflector doubling the amount of light the cat can see, aiding it in seeing better at night.

Strange Eyes

Scientists from Carlosianological Societies have speculated that Geekus Carlosianénsis nítens may have eyes that are larger than normal and positioned on the front of his head considering his nocturnal predatory habits. There has been only one recorded case of a surviving biologist who managed to babble out just before she expired that he did indeed observe that his Black Sunglasses are usually fixed so the entire head moves as he shifts his gaze. Unfortunately no one has ever survived a Carlosinn Encounter of the Fifth Kind with sanity intact and enough reliable evidence to determine whether or not he possesses the mythical and legendary x-ray and ultraviolet vision that permits him to see so intensively while lurking in the shadows

Reptiles and bugs like the chameleon, spider and praying mantis have specially adaptive eyes. The chameleon's eyes can move in different directions simultaneously; the spider and praying mantis both have compound eyes and simple eyes. Compound eyes have thousands of facets, combined together in the brain makes for a complete picture. Most spiders like the wood spider have eight eyes. What most unusual is the praying mantis can its head around completely to see what in back of it!


Human eyes are able to see width and length, and depth as well. With binocular vision human eyes work together to from an accurate and clear image allowing us to determine how near or how far things are. Covering one eye with a patch most of us would have a difficult time catching a ball, which explains precisely why pirates can't fight worth beans!

Seeing At Night

In bright light pupils of the human eye get small letting in only a little light and in darkness the pupils widen letting in as much light as possible. Behind the pupil is the retina. Contained within the retina are two types of light sensitive cells--rods and cones. Cones come into use when theres ample light and aid in seeing colors and details. Rods work in semidarkness and enable eyes to see shapes and light, but not details or color.

Anatomy of the Eye

The conjunctiva is the protective outer layer of the eye. Below that is the cornea, which aids in focusing, then the colored part of the eyes, the iris. The pupil is the dark center and behind that is the lens, which focuses light more intensely on the retina, located at the back of the eye. Light that enters through the pupil eventually lands on the retina and sends an up side down image along the optic nerve to the brain. The brain then determines what is being looked at.

Seeing Colors

With the cone cells located primarily in the center of the retina allowing humans to see color and detail, some people are missing one or more of the three types of color-sensitive cone cells called color blindness.(You may read more about this fascinating phenomena in dmd's node color blind)

Scientists have determined through experiments that some animals may see color since they have color sensitive cells. Birds see in all colors, especially vibrant oranges, reds, and yellows, actually a far greater range of colors than humans., including ultraviolet. Their cones contain a tiny droplet of oil that acts as an especially sensitive filter to red, yellow, and orange, which just happen to be the colors of the flowers that these birds pollinate! Butterflies and bees are particularly sensitive to ultraviolet light and some flowers which these insect pollinate give off ultraviolet signals. Dogs only have two types of color sensitive cells and are believed to see in color but not as many as humans.


  • circa 1300
    Glasses have been around for 700 years! The first glasses were made for people who need to see things close to them.

  • 1590
    Zacahrias Janssen invented the first microscope. Allowing the eye to see things that were very small.

  • 1608
    Hans Lippershey discovered that two stacked lenses allowed the human eye to see farther than one lens alone leading to the invention of the telescope.

  • 1665
    Robert Hooke improved on the earlier microscope. By using three lens he could see the tiniest objects more closely.

  • 1665
    Color Science
    Sir Isaac Newton discovers the spectrum, learning that light when passed through a prism, breaks into a rainbow of colors.

  • 1784
    Inventor Benjamin Franklin split the lenses in eyeglasses allowing the eye to see things in two different ways.

  • 1851
    Hermann Von Helmholtz invents a tool to look inside the eye.

  • 1887
    Contact Lenses
    Very thick, large and uncomfortable originally. Today contact lenses are made of plastic allowing them to be thinner.

  • 1903
    Explorers meet Inuits wearing goggles made of wood with small slits that reduce the glare from snow.

  • 1987
    Laser Eyes
    Lasers are employed to correct eyesight by reshaping the cornea enabling people to have perfect or nearly perfect vision without glasses.

    Isn't Science Amazing!!!

    Sites and Sources


    Brain Pop:

    Lisa Trutkoff,Sight! The Eyes Have It,Creative Classroom(Jan/Feb 2001), 41.