"Blind the prey"? Really? ummmm lets see they hunt at night or in the evening right? They only sparkle in direct sunlight how does this work in any way? I'm sorry but it just seems like it has no real advantages at all. Also why don't they sparkle under artificial light? If there skin is that reflective shouldn't all light reflect off of it? How does something as elastic and supple as skin reflect light in the first place. I know vampires are fictional but most stories I've read had reasons for vampires to have certain abilities.