There’s one species that really comes to mind as a fantastic example of all the remarkable attributes of color shown in all the birds-of-paradise. And this is the Wilson’s bird-of-paradise. If we look at Wilson’s in a still photograph, we’re struck right away with the incredible variety and intensities of colors that we see. You can see he’s got all the primary colors right there. He’s got this incredible blue head. And those aren’t feathers. That’s actually all bare skin. And that blue color of the skin, that’s not pigment, that’s structural color, unlike anything else seen in other birds-of-paradise. That color is made from the proteins inside the skin and how they’re arranged. And you see this bright yellow that’s on the nape and neck, and the crimson red that’s down the middle of the back and also on the coverts of the wings. These red and yellow feathers are a great example of pigment-based colors. Unlike the structural colors they’re always looking bright red and bright yellow from nearly every vantage point. And then there on the tail he’s got these two curlicue handlebar mustache looking tail feathers. When you catch them in the right light sometimes they look incredibly blue, incredibly shiny. This is a good example of that kind of structural coloration that makes intense iridescent. Now if you were to look at them from the underside, there’s even a better example of that “now you see it, now you don’t” trick of iridescence on this brilliant emerald green breast shield. A lot of times it just looks black. But when he gets it lined up, like he does when he’s in his courtship display to the female, it’s this intense bright green color. It’s really extraordinary. Even the legs on Wilson’s are pretty spectacular. It’s another example of structural color in the skin that makes those legs so blue. They have the same kind of structural blue coloration as his head does. But yet perhaps the most hidden feature of color on this bird that becomes obvious in some video is that the inside of his mouth is also colored. And you know, of course, all of these colors that you see in all of these feathers and in the skin are the result of generations of females having selected for males that have them. And all of them are used and utilized by the males in the context of his courtship display.