Do snakes blink?

When you watch a snake, it may look menacing because it does not blink. However, the snake will sleep with their eyes open and it is hard to know when the snake is asleep or awake. The eyes of the snakes do not have eyelids, and this means that they are not able to blink or close their eyes. In the place of the eyelids, there is a clear membrane cover at the corneas and it is called brilles or spectacles. It is normally attached to the skin. However, they are able to close their retinas when they sleep. There are snakes that have round pupils like humans while others have vertical-slit pupils.



Most of the time, the snake spends their time on the ground. They meet the vegetation, grit and dust in their faces while moving within the natural habitats. Spectacles will protect the sensitive corneas so that they do not get damaged or scratch. A thin membrane cannot lie directly at the corneas but is separated by the use of the fluid that looks like tears and moistens the eyes. The scientists want to learn more about the eyes of the snake so that they may develop good contact lenses.

The fluid found in the eyes of the snake is being produced by the tear glands found behind their lenses. There is a pair of the nasolacrimal ducts that will drain the fluid in the mouth roof. Since spectacles have been attached to the skin, then the tears may never overflow to go outside of the eyelids as happens with mammals. This is the reason why snakes can never cry. Because the eye scales are among the parts of the skin, they will also shed while shedding their skin. The mature snake will shed twice or even once in a year and the younger ones that are still growing will shed at least four times every year.

The single eye scales are used to protect the eyes of the snake against injury and to prevent the drying out of their eyes. This means that the snakes are not that able to close their eyes and they are not able to blink and may have to sleep with the eyes open.

When it comes to the snake, it is hard to distinguish if it is asleep or not through looking at its eyes only. If the snake looks totally still, then it is possible that it is fast asleep, but it may also be relaxing, so you should not assume that it is asleep only because it is not moving. There are also some types of lizards that have spectacles instead of eyelids like snakes and you may never know when they are asleep or not.

For more information about whether snakes blink, go to my Snake Removal - How to Get Rid of Snakes home page.

More snake trivia:
Do snakes have bones
What is a snake’s natural diet, and how does it obtain its food?
Do snakes drink water?