To the Greeks and Romans, the owl was a symbol of wisdom and was the companion of their goddess of wisdom. They see very well but most kinds see better at dusk because their eyes, adapted for night hunting, are so sensitive to light that the iris almost closes in strong light. It is supposed that they are particularly sensitive to green, yellow, orange, red, and possibly even to infrared rays which are invisible to us. As with us humans, and unlike other birds, an owl has both eyes set in the front of its skull but they are immovable and cannot be rolled from side to side. This gives the bird's face an uncanny menacing staring expression.
Owls have another peculiarity.
Like hawks, they swallow their prey whole or in large pieces without removing the fur, feathers or bones. These indigestible portions are rolled up by the stomach into compact pellets and ejected from the mouth. The location of an owl' s den or roost is frequently betrayed by a pile of these pellets beneath it. They are clean and dry, do not smell, and can be taken apart to discover what the bird has been eating. Such examination will show that, contrary to common belief, nearly all owls are valuable to mankind.