Final answer:
Private, unobservable mental behaviors are known as innate behaviors. These behaviors are closely controlled by genes and occur naturally in all members of a species whenever they are exposed to a certain stimulus.
Step-by-step explanation:
Private, unobservable mental behaviors are known as innate behaviors. These behaviors are closely controlled by genes and are not influenced by the environment. They occur naturally in all members of a species whenever they are exposed to a certain stimulus. Examples of innate behaviors include a dog drooling when exposed to food or a bird building a nest without being taught.