Scent Into Action

Rodent responses to a whiff of predator may offer clues to instinct in the brain

David Ferrero wasn’t expecting the jaguar to pounce. When he approached the holding pens at Massachusetts’ Stone Zoo, the big cat watched but looked relaxed, lounging on her cage’s concrete floor. Two other jaguars rested in separate cages nearby.

In mice, a sniff of certain odors can trigger instinctual responses related to defense and mating.