Yes, Ratter, we do get to know a range of barks but for the dog to have intended them all for humans means that it knew that the human would know the different meanings of each. All dogs, the world over, speak the same language of barks. Humans, however, the world over, make different sounds, different language, for every one of those messages. That's why I think that the barks are instinctive and intended to tell other dogs in the pack what the individual has seen or sensed, to the benefit of the pack, have evolved for that purpose, and that we humans, or some of us , have merely learned what the dogs are saying. The rarest sound that my little dogs make is the 'baying' noise, when one comes upon a deer and gives chase, and the others join in. That is telling the others, not me; the one needs the help of the others and they need as much help from other dogs around as possible