Hey Marco,
those are raaad facts... cant really believe,
that a blind Chameleon changes his colours to the surroundings...

I could just guess, that it is guessing witch colour by the temperature or feeling. Like harsh wooden ground is more likely brown or cold and slick ones are probably grey, ...
Or do you think it could be some other things like the language of colours, that they emit some kind of signals?? ^^

Anyway thanks for this rad content, really what I was looking for,
all the best from Germany my friend,
Johannes (: