How many times do you ask yourself that it is so rare for you to find blue color in nature other than the butterfly? The wings are not blue, so why is that?
The color blue is rare in nature because there isn't a naturally occurring blue pigment, rather, they rely on physics to create a blue appearance. The wings of the blue butterfly you normally see are covered in small scales that reflect light in different shades of blue. In poison dart frogs, bright blue colors warn predators that the animal is toxic.