How does social facilitation differ from observational learning in chickens?

In the study of animal learning, the distinction between social facilitation and observational learning in chickens centers on whether the animal acquires new knowledge or simply responds to a social stimulus.1

• Social Facilitation: This occurs when the sight of other chickens feeding acts as a stimulus that triggers a satiated chicken to begin eating again. In this instance, the chicken is not learning a new behavior or gaining new information; it already knows how to peck and recognizes the grain as food. The observation merely serves to elicit an existing, well-known response.1
• Observational Learning: This requires that an animal acquires new knowledge or a new response by watching another. For an act to qualify as observational learning, the animal must have been unlikely to perform the behavior in the absence of the observation due to a lack of knowledge. Unlike social facilitation, where the behavior is already within the animal's repertoire, observational learning involves the acquisition of a skill or information that the observer did not previously possess.1