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Remember running your hand along a feather’s barbs and watching as the feather unzips and zips, seeming to pull itself back together miraculously?

That “magical” zipping mechanism of feathers provides a model for new adhesives and new aerospace materials, according to engineers at the University of California San Diego.

Findings are in the Jan. 16 issue of Science Advances – “Scaling of bird wings and feathers for efficient flight.”

Feathers have a “magical” zipping mechanism that pulls itself back together

Properties of Feathers

Researcher Tarah Sullivan, who earned a Ph.D. in materials science from the Jacobs School of Engineering at UC San Diego.

She takes a detailed look at the general structure of bird feathers (without focusing on a specific species).

Sullivan 3D-printed structures that mimic the feathers’ vanes, barbs and barbules to better understand their properties.

"Magical” zipping mechanism in feathers can provide a model for new adhesives and new aerospace materials (Red-tailed Hawk Feather) — “Magical” zipping mechanism in feathers can provide a model for new adhesives and new aerospace materials (Red-tailed Hawk Feather)

Feather’s Spacing Essential for Flight

And how the underside of a feather can capture air for lift, while the top of the feather can block air out when gravity needs to take over.

Sullivan’s findings show that barbules, the smaller, hook-like structures that connect feather barbs, are spaced within 8 to 16 micrometers of one another in all birds.

Suggesting the spacing is an essential property for flight.

“The first time I saw feather barbules under the microscope I was in awe of their design. Intricate, beautiful and functional,” Sullivan says.

Feathers are intricate, beautiful and functional (Woodcock Feather)

“As we studied feathers across many species it was amazing to find that despite the enormous differences in size of birds, barbules spacing was constant,” she adds.

READ: Art Light as a Feather

Feather’s Properties Model for Adhesives

Sullivan believes studying the vane-barb-barbule structure further could lead to the development of new materials for aerospace applications, and to new adhesives.

The structures zipping together the barbs in bird feathers could provide a model for new adhesives and new aerospace materials (Downy Woodpecker Feather)

Think Velcro and its barbs.

She built prototypes to prove her point, which she will be discussing in a follow-up paper.

“We believe that these structures could serve as inspiration for an interlocking one-directional adhesive or a material with directionally tailored permeability,” she adds.

So next time you find a feather on the ground, think about the scientific implications this .0082-gram object provides.