As we saw in the discussion of instinct, many behaviors, though genetically pre-determined to some extent, also rely heavily on learned components. Learning may take place at any age. Information to be learned can come either from other animals or from an animal's personal experience and observations of its environment.
There are two simple types of learning: associative and non-associative. Learning is associative when it occurs with a connection (association) to a positive or negative stimulus; it is non-associative when such a stimulus is absent. Associative learning is often the result of conditioning, which also has two main types. Classical conditioning occurs when two unassociated stimuli become associated through repetition. A well-known example of classical conditioning is the work of Ivan Pavlov, who conditioned dogs to salivate upon hearing a bell ring by repeatedly presenting them with food accompanied by a ringing bell. The dogs associated the ringing bell with receiving food and thus would salivate in preparation for the food they expected to receive when they heard the bell. Operant conditioning requires that the unassociated stimulus become associated with a reward. More complex forms of learning include latent learning, in which a stimulus becomes familiar in the absence of reward or punishment, imitation, and imprinting, the process by which young animals become familiar with other members of their species.