"Our computer modeling done shows that the beak is optimized to an amazing degree for high strength and very little weight," said Meyers. "It's almost as if the toucan has a deep knowledge of mechanical engineering."
In a paper to be published Dec. 1 in Acta Materialia, Meyers and graduate students Yasuaki Seki and Matthew S. Schneider reported that the secret to the toucan beak's lightweight strength is an unusual bio-composite. The interior of the beak is rigid "foam" made of bony fibers and drum-like membranes sandwiched between layers of keratin, the protein that makes up fingernails, hair, and horn. Just as the hook-shaped barbs on cockleburs inspired the development of Velcro, Meyers said the avian bio-composite could inspire the design of ultra-light aircraft and vehicle components with synthetic foams made with metals and polymers.
"The big surprise was our finding that the beak's sandwich structure also behaves as a high energy impact-absorption system," said Meyers. "Panels that mimic toucan beaks may offer better protection to motorists involved in crashes."
Toucans are highly social, noisy residents of rainforests in the Amazon, although the birds live as far north as Mexico. They use their extremely large and often brightly colored beaks for a variety of purposes, from gathering fruit from the tips of tree branches, to defending themselves.
Bird beaks are typically either short and thick or long and thin. The Meyers team decided to prospect for a novel material in toucan beaks because they are both
Contact: Rex Graham
University of California - San Diego