Butterfly

I was in the Ulster Museum today. Did you know that unlike most colours in animals, blue is almost always not a pigment, and in fact animals which appear blue often only do so because of the *shape* of their scales at a microscopic level. The only known exception to this, I believe is a very special type of butterfly. Not this butterfly. To suggest that it might be this butterfly either underestimates the rarity of the creature, or overestimates the budget of the Ulster museum.