“Hey, look at that!”  When someone says that in a crowd of people, you and everyone around you probably find yourself looking in the direction the speaker is facing rather than at the speaker.  Even if you can’t see the speaker, most people will inevitably look in the direction the person was looking when they spoke out.  Based on the speakers vocal cues we are able to extract the location of interest given as an indication of direction.  Humans are able to interpret these vocal cues for direction at the age of one year.
Research has shown that dogs and puppies are extremely good at understanding human visual cues in order to find hidden food based on just a slight glance from a human in the foods direction and dogs pay careful attention to our voice sounds.  Dogs show mental abilities that are equal to that of a two-year-old human therefore it stands to reason that they should be able to gather information about an interesting location based only on the vocal cues that indicate the direction a speaker is facing.  So, a team of researchers at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany did a series of studies to test this theory based on the same procedure previously used to test this ability in human one-year-old kids. 
The experimenter stood behind a screen with two identical boxes placed on either side.  One box contained a bit of food while the other contained only the scent of food.  The experimenter ducks behind the screen out of the dog’s sight, faces one of the boxes and excitedly says something like “Oh look; this is great!”  Will the dog pick up on the vocal cues showing the direction the experimenter is facing and use this information to lead to the correct box?  The experimenter positioned herself closer to the wrong box, meaning that, if the dog is just cueing off the sound of her voice instead of using information about the direction she is facing, the dog will choose the wrong box.
The results showed that dogs are good at picking up the directional information from the sound cues indicating the direction the speaker is facing thereby accurately responding to them.  This is important since chimpanzees, which are considerably smarter than dogs, cannot do this.  These results raise other questions such as, have dogs developed the ability to understand direction from voice cues as part of the domestication process?  Did we select dogs who were prewired with this ability in their genetic makeup or did dogs simply learn the ability as a result of living in close association with people?
To answer these questions, the research team tested a group of 8 to 14 weeks old puppies to see if they had this ability indicating it may well be coded in their genes.  The results showed the puppies did very well, even better than the adult dogs however, these puppies had either been living or in close association with humans.  When the researchers tested a group of puppies who had mostly been in the company of their littermates, the results were extremely different.  Performing at a chance level, they seemed unable to pick up the information as to which direction the speaker was facing.  You can interpret these results in two ways.  One, the ability to interpret directional sound cues is learned.  Two, the puppies in the mostly isolated litter were not adequately socialized to people therefore considering them to be sufficiently less important to cause close attention to sound information coming from them.
Humans are very important in the canine mind as they use our gestures, the sounds we make and the direction of our gaze to map their environment as well as communicating information about the world to our dogs, whether intentionally or not.