Ask A Scientist
Do all animals see different?
Asked by: Rebecca Curtis
School: Maine Endwell Middle School
Career Interest: Fashion designer
Answer from Debbie Dittrich
Research Support Specialist, Binghamton University
Research area: Teardown analysis of electronic packages
Interests/hobbies: Docent at the Binghamton Zoo, nature photography, gardening
Think about all of the different habitats that there are on our planet, each filled with animals adapted to live under those specific conditions. Every creature also has its own unique needs for food, shelter, and places to hide and raise its young. So you can imagine that different animals would see differently.
Birds, for example, are very dependent on eyesight for navigation and finding food and probably have the best eyesight of all vertebrates. Their eyes are large, sometimes even weighing more than the birds brain. Some can see colors in the ultraviolet spectrum, colors we can’t see. Raptors have particularly acute vision. An eagle can spot small prey from a mile away!
At the other extreme are animals that spend their lives in dark places; underground, in caves or deep in the ocean where little light penetrates. Their eyes are tiny or sometimes nonexistent, their eyesight is poor and they rely more on other senses.
Location of eyes on the head is also important. Predators typically have eyes on the front of their face, allowing the eyes to focus together to create one image (binocular vision). Thus the creature has good depth perception, which is extremely important for a hunter. Prey species often have eyes on the sides of their heads. Each eye forms its own picture (monocular vision). With this strategy the animal has a blind spot directly in front of its face, a small angle of binocular vision further out, and a blind spot behind its head. Otherwise, it can see all around itself and is constantly watching for any motion to expose a lurking predator.
Frogs and alligators have eyes on the top of their heads, and lie submerged in the water with just their eyes and nostrils sticking out so that they can breathe and observe their surroundings while remaining hidden. They can see in almost every direction and have some binocular vision. Four eyed fish also have eyes on top and can see both above and below water at the same time. The bottom half of their eyes see under water while the top half see above water.
Many animals see colors, and birds are not unique in seeing ultraviolet colors. Nocturnal animals sacrifice color vision for the ability to see well in low light.
As you can see, there is an endless variety of fascinating ways in which animals view their world.