its hard to think that colors could change mood in your cham but chameleons are the most visually reliant out of all animals and they communicate through visual cues conveyed by color changes and of course posture. so it could be possible that certain colors bother certain species of chameleon...
I found this very interesting. tongue testing among chameleons remains an enigma. all species, ages and genders of chameleons press a bilobed organ near the front of the tongue against objects for a moment. The organ has no function in feeding. Because chameleons wipe the cloaca on branches...