Scents and Sense
1) The barking of dogs, meowing of cats and the singing of birds are similar to the human language because they are all forms of communication. These communications all transmit emotions or messages that are understood by other species members. For example, there are different types of barks by a dog that is barking defensively as opposed to a dog that is barking for a treat. A cat will meow differently when it is wanting to be fed as to being threatened by another animal. As with a bird, it's happy chirps can be different from it's call of fear or warning of danger. Likewise, we too communicate our basic needs and fears as dogs, cats and birds do. Our language however, is far more complex and a lot higher thinking than any dog, cat or bird. In our language we have the ability to communicate in past, present or future tense because we have a sense of temporal passing.
A dog though, will bark, communicating that it is hungry right now, or right now it is cold or right now its tail was stepped on. Humans are not limited by what is currently happening but we can express what did happen or what will happen.
2) A parrot does not speak excellent English just because it can produce complicated sentences like, "I want jam with my cracker." Speaking is not merely generating sounds. It involves an understanding of what is said or heard. The parrot is simply copying sounds and noises that have been repeated to it, and then producing the same noises itself. There is no awareness of the significance of the sounds, just a copy. Words are symbols. For excellent English, these symbols must be understood, and a parrot cannot do this.