Unveiling Filoplumes: The Overlooked Feather with a Big Story

Vanya Gregor Rohwer slid open a drawer to display the rich pink spread wing of a roseate spoonbill, one of thousands of mounted wings at the Cornell University Museum of Vertebrates. He pulled up a long flight feather to expose, at its base, a palm-tree shaped feather so minuscule it could easily be missed. For a long time, this tiny feature called a filoplume was indeed obscure. “The history of research on filoplumes is not super robust. They are kind of an overlooked feather,” said Dr. Rohwer, a curator of birds and mammals at the museum. “They were considered a degenerate feather or a useless feather, a relic.” No longer. Dr. Rohwer and his father, Sievert Rohwer, an influential feather researcher and curator emeritus at the Burke Museum at the University of Washington in Seattle, believe that the tiny filoplume is a key player in the monitoring and maintenance of birds’ feathers, which keep them airborne. Ever since feathers first appeared on dinosaurs around 150 million years ago, they have been evolving. Now there are six types of feathers on a bird’s body, including filoplumes, and all are made of keratin, a dead substance like human hair.