Are you familiar with Pavlov’s dog experiment? Pavlov showed that dogs could be conditioned to salivate at the sound of a bell by associating a bell’s ring with food. After repeatedly feeding dogs after the sound of a dinner bell, dogs began drooling as soon as they heard the bell, even when no food was presented. This phenomenon is known as classical conditioning.
Other studies have shown that classical conditioning occurs not only in dogs, but also humans, and even trout. Through laboratory experiments, scientists have proven that trout are capable of learning, and remembering to associate certain actions with feeding. In a controlled study, trout that would strike at a red lever were awarded food pellets, and learned that striking the red lever would repeatedly present food. My point is that trout, who spend a large portion of their lives scanning for food items, are constantly learning from their environment, and applying that knowledge towards eating, and surviving.