Dull Brown or Green?

There is a myth about Arabian Chameleons (Chamaeleo arabicus) from Oman, saying that populations east of Salalah live on the ground, are colored dark brown to black, never changing to yellow and green... 

Well, in general, while foraging, this species is often found on the ground, crossing roads (there is a quite high number of roadkills I have seen). 

Also, when on dark ground, but also on dry bushes, they often turn brown or even. Lack (especially when stressed). But, they turn green when changing the environment or while sleeping - same as this male, found on ground in late afternoon, but spotted same day at night sleeping in the typical bright green colorstion with blue and yellow markings...