I've researched a few forms of animal communication and happened upon some very interesting and unexpected forms of communication between animals. The most shocking to me is that ants communicate using chemicals. Depending on the species, ants can release between 10 and 20 different chemicals from different glands on their bodies. The chemicals released can mean a variety of different things: signaling danger and even signaling that a fellow ant is dead. This is by far the strangest form of animal communication I have come across. I was also surprised to learn that lions have a roar to locate one another. This roar is softer than the one used as a warning to other animals.
Although I believe that animals can communicate in their own way, I don't believe these forms of communication are a language. I believe that language is the spoken word with meaning given to individual units of speech. Just because different species of animals can communicate and understand their own form of communication does not mean that they are using a language. The languages we use as humans are simply a form of communication spoken among our own species. In my opinion there is no such thing as animal language, but there is definitely animal communication. I refuse to believe that animals communicate through language until I hear words (other than a bark) come out of a dog's mouth.
I like that you have brought up this topic in your blog. From the time I was very young, I always wondered what types of communication my dogs used with each other and other dogs they encounter. Like you mentioned with the lions, when dogs bark, do the different pitches and sound levels mean something to another dog who is listening? I agree with your statement that animals do not communicate through language, to an extent. Although they do not speak words, maybe these different types of barks and noises they make are a form of language that we humans are unable to detect.