When dogs smell something they are not just registering a smell, they get an entire story. They can smell pheromone, which is not only found in the urine and fecal, but on the skin and fur. From this they can tell a lot about another dog or human including if they are male or female, what they ate, where they have been, what they have touched, if they are ready to mate, if they have recently given birth, or had a false pregnancy, and what mood they are in. They have even been known to smell cancer on people, alerting them to it and saving their lives. This means when your dog smells another person, tree that another dog has peed on, pant leg that another dog has rubbed up against, or chair that someone has sat in, they are actually reading a story, not just smelling an interesting scent. While a human will smell something like spaghetti sauce as one smell, a dog smells each individual ingredient. Unlike humans, dogs can move their nostrils independently, allowing them to know what direction a smell is coming from.
A dog can both sniff and breathe. These are two different functions. Breathing is for air, but when they sniff with short breaths they actually save some scent that does not get exhaled. When a dog is overheated and actively panting, its sense of smell is reduced by as much as 40 percent as it uses the air to cool itself rather than for smelling.
Puppies have heat sensors in their noses to help find their mother during the time when their eyes and ears are closed. These sensors disappear by the time they are adults.
Originally posted by marbles87
reply to post by pheonix358
Missing my point. Of course a dog won't put on a suit and tie and answer on the stand but info provided could have offered evidence on wether GZ or TM back tracked or lied about their paths.