Researchers around the world have worked to create super black substances that absorb the majority of light, and a new study details a type of bird feather that is comparable to them. These super black birds of paradise feathers are so black, they absorb up to 99.95% of light, depending on where the light is coming from, resulting in a super black plumage. This, it turns out, helps the birds win over a potential mate.
The study analyzed feathers from five birds of paradise species, finding that when viewed from straight ahead, the feathers absorb 99.95% of light, resulting in an incredibly black appearance. This, researchers note in their study, may be the evolutionary result of the birds’ courtship displays, which involves puffing up, flattening out, and showing off a colorful patches of feathers.
It’s hard to visualize that courtship ritual, so check out the BBC Earth video above to see it in action. It’s a bizarre dance that involves the male bird showing off brightly colored patches; what better way to highlight those colors than contrasting them with incredible darkness?
That high absorbency level pertains to incident light; the percentage drops to 96.86% when the light is coming at the feathers from the sides rather than straight on. Still, that puts the feathers up close to the same level as super black substances created by humans. This is made possible by the feathers’ unique structure, which causes light to bounce around in the structures, either being absorbed (super black) or reflected (the incredibly shiny, striking colors).
The study reads:
SEM, nano-CT, and ray-tracing simulations show that super black feathers have titled arrays of highly modified barbules, which cause more multiple scattering, resulting in more structural absorption, than normal black feathers. Super black feathers have an extreme directional reflectance bias and appear darkest when viewed from the distal direction.