Did you know? Dogs often bark at mail carriers or package delivery drivers because their territorial instincts make them want to drive away unfamiliar intruders. Each time the dog barks and the person leaves, the dog believes its barking worked, reinforcing the behavior. This is often described as negative reinforcement (the “intruder” leaving removes a perceived threat), though other forms of reinforcement and conditioning can also contribute. #fyp Voiced By: OneLineDerek Note: This sketch is b