Artificial whisker reveals source of harbor seal’s uncanny prey-sensing ability
Harbor seals have an amazingly fine-tuned sense for detecting prey, as marine biologists have noted for years. Even when blindfolded, trained seals are able to chase the precise path of an object that swam by 30 seconds earlier. Scientists have suspected that the seal’s laser-like tracking ability is due in part to its antennae-like whiskers. Now engineers at MIT have fabricated and tested a large-scale model of a harbor seal’s whisker, and identified a mechanism that may explain how seals sense their environment and track their prey. The team found that a seal’s whiskers serve two main functions in sensing the environment: first remaining still in response to a seal’s own movements through the water, and then oscillating in a “slaloming” motion in response to the turbulence left by a moving object. In their experiments, the researchers observed that once the fabricated whisker enters the wake left by a passing object, it starts...