Canine Communication

In the last two decades scientists have become more and more curious about the dog’s (Canis familiaris) seemingly innate ability to understand human cues. Historically this ability has been overlooked or dismissed in any non-primate species; dogs in particular were dismissed as an “‘artificial’ species.” (Mikolsi, Topal, & Csanyi, 2004) Then, just before the turn of the century, a trend in research began to emerge: dogs were showing ability near or above that of primates in human gaze driven studies. Following an initial study by Brian Hare, Josep Call and Michael Tomasello in 1998, researchers began to attempt to answer the questions: “How much do dogs understand about human cues?”, “What is responsible for the dog’s ability to do this (age, breed, training, domestication)”, and “If this is a learned ability, when do dogs learn this ability?”
Although researchers agree that the domestic dog has an uncanny ability to both interpret and utilize human-given cues, there continues to be debate regarding the origin of this ability. One school of thought posits that the ability to read human cues is a result of the dog’s domestication over thousands of years by humans. This is known as the “Domestication Hypothesis”. Others posit that this is not enough to explain the dog’s ability. This second group favors the “Two-Stage Hypothesis”. This hypothesis suggests that, along with domestication, dogs must have been given opportunities to enjoy positive interactions with humans, and their age and level of training must be taken into account and their lifelong experiences.
This review will cover research in the area of canine cognition from 1998 up to the present year, 2015. Generally each study reviewed was performed with the object choice task and human given cues. An object choice task is one in which an informant indicates the location of the hidden item to the subject (canid) by looking toward or pointing and looking toward one of two opaque containers (Hare & Tomasello, Domestic Dogs (Canis familiaris) Use Human and Conspecific Social Cues to Locate Hidden Food, 1999). Scoring was done based on the number of times the dog followed human cues (such as pointing or gazing, or a combination of both) and correctly chose the baited object. Before trials, dogs underwent training (commonly referred to as “pretraining”) with the experimenters in order to learn that the objects placed before them held food (small treats used to reinforce the dogs’ correct behavior; commonly called “reinforcers”). Some studies, where applicable, also included temperament testing in the form of questionnaires filled out by their owners. Most studies done have focused on human-given cues (a point, a gaze, a physical marker or any combination or variation thereof). However, some studies have incorporated conspecifics (others of the same species) and tested dogs’ ability to follow their cues in order to find hidden food.