Why Blue Jays Aren’t Really Blue

Blue jays are not truly blue, they just look that way. 

Most colors in nature come from pigments that absorb and reflect light, but a blue jay creates its color through structural tricks: microscopic layers and air pockets that scatter blue light back to our eyes. When light shines through its feathers, the brown pigment underneath is revealed. If those feathers are ground down, the delicate structures break apart, and the blue vanishes completely.