Watching my dog pee and smell pee for inordinate amounts of time has led me to the following. This is what happens to a mind after spending too much time walking a dog.
Humans communicate with each other through various means, one of the more important being through voice. Voice is created by the flow of air from the lungs out through the mouth, across the vocal cords. Voice is "received" by the recipient, who detects the sound through receivers in the eardrums that are capable of sensing a particular spectrum of sound waves. Different elements of communication are expressed through altering the flow of air, including the force of the expelled air (eg, volume) and the shape and type of the sound waves (eg, through vocal cord vibrations and changes in the shape of the mouth).
So basically, we communicate by forcing air out through our mouths and purposefully altering the flow through various means to generate specific messages.
Now, consider this:
Dogs communicate with each other through various means, one of the more important being through urine. Dogs spread urine through its controlled flow from the bladder out through the urethra. The scent is "received" by the recipient, who detects the smell through olfactory receptors in the nose that are capable of sensing a particular spectrum of odors.
Now, the spectrum of odors detectable by dogs is, we believe, much wider than that capable of being detectable by humans. In fact, the part of the dog brain that controls smell is 40 times larger than in humans, and it is believed that the sense of smell in dogs is 1,000 to 10,000,000 times better than humans.
Which leads ultimately to the hypothesis: Dogs communicate different and perhaps specific messages to each other through urine by purposefully altering the flow or, perhaps even, the content of their urine, thereby altering the scent of the urine in ways that we neither suspect nor can detect.
Discuss.