Why Do Chameleons Retract And Protrude Their Eyes?

19/07/2020

Chameleons's eyes are sunken.

"He is dehydrated!"
"He is ill!"

...You will hear people shouting from all corners...

Well, might be, but...
We tend to misunderstand chameleon's eyes same, as we tend to misunderstand many of other aspects of their biology.

Namely:
If a Chameleons is heavily dehydrated, then as a rule his eyes will be sunken in the eye holes. But, if chameleons eyes are sunken in the eyeholes, it does not automatically mean that he is dehydrated!!! There are namely many other reasons why chameleons retract their eyes deep into the eye sockets.

So, is it possible that a dehydrated Chamaeleon has his eyes not sunken in the eye holes? HARDLY.
AND
Is it possible that a Chamaeleon that has eyes retracted deep into the eyeholes is in fact absolutely healthy? YES OF COURSE! And, surprizingly for many, in the most of the occassions this exactly will be the case!

When do the chameleons retract their eyes?

It it happens basically in two modes: passively and pro-actively.

PASSIVE RETRACTION
happens, when the chamaeleon cannot control it, as it is a result of some external or internal factor, such as:

- Dehydration
- Opthalmic disease
- Respiratory disease
- Temporal gland infection
- Any discomfort or disease
- Parasital infection
- Overheating
- Sleeping, especially when in position head up

PRO-ACTIVE RETRACTION
happens, when the chameleon deliberately lets his eyes sink deep into the eye sockets for different reasons, such as:

- Stress
- Protection against injuries during combat
- Protection against injuries during predation (or what looks like that)
- Protection against injury while retracting the tongue during every single shooting at prey

So, you see that the reasons why the chameleons eyes can be situated deep in the eye sockets are very many, not dehydration only.

Interestingly, chameleons can not only retract eyes into the eye holes but they can also significantly protrude them and they do so passively and pro-actively.

PASSIVE PROTRUSION
happens, when the chamaeleon cannot control it, as it is a result of some external or internal factor, such as:

- Hyperhydration
- Opthalmic disease
- Respiratory disease
- Parasital infection
- Sleeping, especially head-down

PRO-ACTIVE PROTRUSION
happens, when the chameleon deliberately lets his eyes protrude deep into the eye sockets for different reasons, such as:

- Stress
- During imposing other male
- During combat
- During antipredatory mechanisms like thanatosis
- During eye cleaning

The chameleons can change the state of the eyes almost immediately they can change from having eyes protruded like a ball in a second to normal, same as they can modify them from normal state into deep sunken eyes within a break of a second when stressed.

Chameleons are masters of disguise, they foul us permanently, it is their nature to pretend what is not reality... So, do not get fouled looking into a notorious liars' eyes again! Whenever you want to assess the state of a chameleon, look best in the eyes last, after yiu have seen all the other aspects before, rather than first... They may foul you...

Fantastic creatures indeed!