Overview
- Published in Science, the interdisciplinary study from MPI-IS with Humboldt University and the University of Stuttgart used micro-CT, electron microscopy, nanoindentation, 3D-printed models, and simulations to probe elephant whiskers.
- Elephant trunk whiskers have a flattened, blade-like cross-section with a hollow base and internal tubules, a porous architecture that cuts weight and resists impacts in whiskers that do not regrow.
- Nanoindentation found a pronounced stiffness gradient from a rigid, plastic-like base to a tip about 40 times softer, like rubber, which shapes how vibrations reach touch-sensing cells at the follicle.
- The gradient encodes where contact occurs along each whisker, helping elephants perform fine tasks such as picking up peanuts or tortilla chips; elephants are born with roughly 1,000 trunk whiskers, many anchored in wrinkles.
- These whiskers differ from rodents’ uniformly stiff, solid, circular whiskers and resemble domestic cat whiskers in having a functional gradient, a design the authors say could inform low-computation tactile sensors for robots.