The high mountain cloud forests are one of the most magical habitats in all of New Guinea. So it’s appropriate that these forests would be the home to one of the most magical birds-of-paradise, the ribbon-tailed astrapia. It really is otherworldly to see. The ribbon-tailed astrapia gets its name from the tail of the adult males, which is about three times as long as the body of the bird. This is one of the longest, if not the longest tail lengths relative to body size of any bird in the world. And yet, as extreme as they are, these are still feathers like any other feathers on the bird. And every year an adult male astrapia will lose those two feathers of his tail during molt and have to re-grow the whole entire thing. One of the things I love most about the ribbon-tailed astrapia is how its extremely long tail has really come to defy everything that we think about the role of feathers on birds. Typically we associate feathers with basic function of survival in birds – aiding in flight, keeping warm, keeping birds dry – and yet these feathers defy all those things. Here you have this three foot long tail that hinders flight, clearly does nothing for keeping warm, and it often gets in the way when the bird is trying to forage. And it’s at these times, when you see the male fly with a struggling undulations flight or with his tail wrapped around a branch while he’s trying to forage, that you can really come to understand that this is an adaptation produced by sexual selection and not the product of natural selection adding to some survival advantage.