Answer: Extinction has occurred.
Explanation:
In psychology, the extinction refers to the process of weakening of a conditioned response by the respondent. This actually results in decrease or disappearance of a particular behavior response.
In the given situation, the dog is showing the trait of salivation in the behavior but after the occurrence of number of trials the dog is not receiving any food this is a tiring situation for dog which made it to stop salivation. Thus here, the extinction of behavior that is salivation has occurred.
Key physical features. All three species share similar physical characteristics - a relatively small body and a 'robust' or strongly built skull including large lower jaws with extremely large molar teeth.
Explanation:
Classification system are system with distribution of classes created according to common relations or affinities.