She says that dogs probably bark more than other animals because of our long history with humans on our road to domestication. What they found is that dogs bark when they feel conflicted about something--the urge to run away from a predator conflicted with the urge to protect our food. Dogs bark more than other animals since we are put in conflicting situations more often than non-domesticated animals.
But you wonder, how come my dog always barks when it is dinner time? Because you taught him that he gets fed if he barks at dinnertime! Lord explains, "Dogs do quickly learn the simple cause-and-effect relationship between their bark at 10 p.m. and the fact that you’ll get right up and take them outdoors. It’s true, but in our view it’s going too far to suggest the animal is intentionally referring to a specific activity." Rather, it has just learned cues, as it does when it learns to sit or beg for a treat.”
Basically that means that we only know that our bark means something specific if you taught us that it does. Some dogs I know just seem to like barking for the heck of it! Why do you think your dog barks? Leave your thoughts in the comments section!