An optical illusion, like a magic picture. If you stare at them really hard they will disappear.
Yes, all mammals' eyes have an iris.
The Iris.
The iris is the colored part of the eye. When you say that someone has blue eyes or brown eyes, you are commenting on the color of the iris. Look at a dog's eyes and you will see that dogs do, in fact, have an iris. The iris is a ring of muscle that surrounds the pupil, which is the opening into the eye through which light enters. The iris is able to contract and expand to control the amount of light entering the eye. This helps our eyes (or a dog's eyes) to adapt to different levels of light.
That you have two iris's. Not really hard to figure out.
iris
This is determined by the positioning of pigmented cells in the iris of the eye. Blue eyes have the pigment at the back of the iris, dark eyed people have the pigment throughout the iris.
The lines in the irises are called as the iris pigment epithelium and the iris stroma.
The iris receives light and the cone cells located within the cornia determine color
The coloured part of the eye is the iris.
it is known as Iris. contraction or relaxation of iris alters the size of pupil.
The iris.
The sheep has brown eyes.