Male peacocks put on quite a show for their mates, and now scientists understand more of what goes into their wiggles
This male peacock is trying to impress a lady friend. He fans his long train, then violently rattles his feathers. New research reveals the biomechanics behind these flashy feathers.
Researchers took slow-motion footage of peacocks showing off and also shook feathers in the lab.
In slow motion, the eyespots seem to float on a shimmering background. They stay put because they have a different structure than the rest of the feather. Each eyespot barb has microhooks that bind it to its neighbor. When the feather shakes, the eyespot moves as one.
A peacock’s tail strums its train feathers like guitar strings. When peacocks are flirting, they shake their feathers about 25 times per second. That takes a lot of effort! Properties like the length and stiffness of a material give it a natural preference to vibrate at specific rates. Those are called resonant frequencies. The researchers found that peacocks wiggle their feathers right at those frequencies, which might help them conserve energy. That might help them save energy while still putting on a vigorous show.
But males with longer and heavier tails shook them faster, not slower as the resonance would predict. They might be putting extra oomph into their courting, but scientists aren’t sure why—or if the ladies even notice.
[The above text is a transcript of this video]
Executive Producer: Eliene Augenbraun
Producer: Lydia Chain
Videography: Roslyn Dakin
Stock Audio: AudioBlocks
Special Thanks: Roslyn Dakin, Suzanne Amador Kane, James Hare, Erwin Huebner
Dakin R, McCrossan O, Hare JF, Montgomerie R, Amador Kane S (2016)
Biomechanics of the Peacock’s Display:
How Feather Structure and Resonance Influence Multimodal Signaling.
PLoS ONE 11(4): e0152759. doi: 10.1371/journal.pone.0152759