Suzanne Amador Kane, a physicist at Haverford College, in Pennsylvania, was thinking about visual signals by animals — mostly come-ons and warnings.

She was viewing various courtship videos online when she found some impressive high-speed recordings of the bird that defines showiness — the peacock.

They not only fan out those spectacular tail feathers — called a train — to tempt pea hens, but they also shake them in a behavior called train rattling. Dr. Kane noticed that the feathers “were resonating like cantilevers” during the rattling.

A cantilever is commonly defined as a beam or girder fixed at one end. But, in physics, it could also be a feather, or a stalk of dried hay or a pickup stick fixed at one end.