Mating season is a violent time for many animals. Male platypuses stab each other with the venomous spurs on the back of their legs. Peacocks aim nasty kicks at interlopers. And male deer literally lock horns, jockeying for supremacy. Yet despite the immense force created by these clashes, their antlers rarely break. Now scientists say they understand why. They published their findings in the journal ACS Biomaterials Science & Engineering.

While slightly uncomfortable to watch, the sparring of male deer is less dramatic than you might imagine. It’s less like a high-speed car crash and more like two texting commuters running into each other on the sidewalk. And then not letting go.

Researchers from Queen Mary University of London (QMUL) set up antler bone samples under high-powered x-ray scanners, then squeezed and pushed them, watching how the antlers would behave at the microscopic and molecular levels.

The secret to the antlers’ durability, the team discovered, is the unusual structure of the fibrils (teeny-tiny fibers) within: alternating rather than lining up evenly.

"The fibrils that make up the antler are staggered rather than in line with each other,” first author Paolino De Falco said in a press statement. “This allows them to absorb the energy from the impact of a clash during a fight.”

The researchers say this clever setup could translate well to nanomaterials and future technologies.

"Our next step is to create a 3D printed model with fibers arranged in staggered configuration and linked by an elastic interface," said co-author Ettore Barbieri. "The aim is to prove that additive manufacturing—where a prototype can be created a layer at a time—can be used to create damage-resistant composite material."