Bay (dog)

Dog communication is the transfer of information between dogs, and also the transfer of information between dogs and humans. Behaviors associated with dog communication include eye gaze, facial expression, vocalization, body posture (including movements of bodies and limbs) and gustatory communication (scents, pheromones and taste). Humans communicate with dogs by using vocalization, hand signals, body posture and touch.

Both humans and dogs are characterized by complex social lives with rich communication systems, but it is also possible that dogs, perhaps because of their reliance on humans for food, have evolved specialized skills for recognizing and interpreting human social-communicative signals. Four basic hypotheses have been put forward to account for the findings.

The pointing gesture is a human-specific signal, is referential in its nature, and is a foundational building block of human communication. Human infants acquire it weeks before the first spoken word. In 2009, a study compared the responses to a range of pointing gestures by dogs and human infants. The study showed little difference in the performance of 2-year-old children and dogs, while 3-year-old children's performance was higher. The results also showed that all subjects were able to generalize from their previous experience to respond to relatively novel pointing gestures. These findings suggest that dogs demonstrate a similar level of performance as 2-year-old children that can be explained as a joint outcome of their evolutionary history as well as their socialization in a human environment.

One study has indicated that dogs are able to tell how big another dog is just by listening to its growl. A specific growl is used by dogs to protect their food. The research also shows that dogs do not, or can not, misrepresent their size, and this is the first time research has shown animals can determine another's size by the sound it makes. The test, using images of many kinds of dogs, showed a small and big dog and played a growl. The result showed that 20 of the 24 test dogs looked at the image of the appropriately sized dog first and looked at it longest.

Depending on the context, a dog's barks can vary in timing, pitch, and amplitude. It is possible that these have different meanings.

Additionally, most people can tell from a bark whether a dog was alone or being approached by a stranger, playing or being aggressive, and able tell from a growl how big the dog is. This is thought to be evidence of human-dog coevolution.

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