Chameleons are often called solitary.
They are animals with deep sense of "community" approach, they are highly social! They have complex mechanisms of intraspecific communication, they have their territorial behavior, they have rituals and modes and patterns etc etc.
What fouls us in that respect is anthropomorphism and explaining the reptile (chameleon) behavior using irrelevant (or partly relevant) mammal or bird models.
The chameleons namely exhibit all their social behavior not from close proximity
BUT over DISTANCE!
They in fact work in the environment as a meta-organism, when a local
population is conquering a territory and utilizing the beneficial parts of it the best efficient way possible. This is why they spread almost hmomogeneously in suitable habitat. This is why they run from each other till they reach the margin of a territory...
This is why they get closer to each other but not breaking the margin of aggression limits. These two antagonistic substrategies allow them to build a 3D web-like presence in the conquered territory...
So, to get practical,
The PROXIMITY as one of the parameters of social behavioral models is in chameleons extended if compared to many other animals. And they get deeply social without physical contact with each other: they rely on visual contact (as they have no other real option due to limited function of all the other sensory organs with some exceptions like the Vibrations - but let us not complicate things unnecessarily).
The proximity has in fact three threshholds (distances) defining four ZONES:
1. INTIMATE ZONE defined by "intimate distance" (which is about 10% of the Total length) is the zone of possible physical contact and is in adults exclusively entered just for reproduction
2. AGGRESSION ZONE defined by "aggression distance" (which is in adult males about 5times the total length, in males/females about half of it, and in young it is missing) is the zone of possible intimidation, fight, physical attack and harming each other with the goal to get him/her to leave the territory and keep distance
3. COMMUNICATION ZONE defined by the "visibility distance" (depending on species and terrain, environment, foliage etc etc from several meters to several hundreds of meters and limited by seeing each other only. In this "safe zone" over a "safe distance" the most intraspecific communication happens.
4. IGNORANCE ZONE, the zone beyond visibility, where no sight/visual contact happens as no is actually possible.
So, a sight/visual contact is absolutely NORMAL for them and its absence can lead to behavioral pathology - increasing the thresh-holds of aggressive behavior e.g. and fostering its intensity.
So, what is the implication to the captivity?
1. As the visual contact with congeners is natural, it should be provided
2. The distance of possible visual contact should exceed the aggression limit (easy e.g. on opposite sides of the room)
3. If no congeners are available, a mirror can be placed opposite the cage to stimulate the chameleon (they do not recognize their own picture as their own and consider it another chameleon)
4. Immediate vicinity less than aggression limit should be avoided, through intelligent solutions as foliage or non-transparent separators (some mesh can be by some species and specimens considered a visual barrier)
5. Animals are to be closely observed and based on their behavior, adjustment need to be made
6. It is a general behavioral pattern, not a law: there is individual as well as species-specific variability and deviations
- Social pathologies
- Increased aggression
- Attacking females by males
- Increasing level of force in conflicts leading to killing each other (in males) or to extreme stress
- Aggression amongst females
- Females permanently unreceptive
- Slower growth