idk if this is true with beardie's but with a lot of desert reptiles not just lizards they will change their color to black on 1 side and white on the other... the black side is to the sun to gather as much heat as possible and the white is on the other side and it is used just to break up the outline so it is not as noticable to prey as if it would be all black... just a thought that came to my mind....