The dog’s superhuman sense of smell is much fabled and very well known. Especially in comparison to human beings, the sheer number of smells a dog remembers and the remarkable accuracy with which it can differentiate between them, even when they are cluttered or far off, is amazing. It is put to use in several human endeavours, most famously of course, in the case of police dogs.
The significance of the sense of smell in a dog’s life takes a wee bit of effort to understand from the point of view of a human being. Sight is our primary sense, in that it is the one which most shapes our experience of reality and helps us formulate a response to it. We see things as they happen and this fundamentally shapes the way we act and the way we store and recollect memories. For a dog however, the sense of smell is a much more primal one and is definitely most useful for survival.
Dogs, just like us, smell through specialised oflactoreceptor cells which are located in their noses. While they are completely analogous to the olfactoreceptors we’ve got, an average human being has only got 5 million of them to say, a bloodhound’s 300 million. In addition, the centre of the brain that is responsible for processing these olfactory signals is also proportionately much larger in dogs. This enables them to store and recgonise a lot more olfactory signals. The difference this variation in biology makes is staggering: If you can pick up and discern a scent clearly, a dog can pick the same scent up with a thousandth of the quantity in a packed football stadium located 2 miles away. In addition, if it recognises the components, it can distinguish them as well.
This phenomenal capability of dogs has several applications and manifestations in every day life. The more famous image that this conjures in most of us is that of the universally revered police dog. While law enforcement is an area where this sensory gift of dogs finds wide application, it does manifest itself in other more overlooked areas. For instance, let’s take the apparent emotional compatibility of dogs with humans. It’s the stuff of legends. This, many experts argue, is the result of a dog getting a whiff of the hormonal shift that precedes a substantial emotional shift. i.e they can literally smell our anger or happiness! What more, dogs have also been shown to be able to discern small biochemical changes that accompany cancer and are being used to arrive at diagnoses.
Furthermore, when dogs are at a place, they are capable of constructing a complex olfactory image that interlaces the recent past with the near future and the present using residues of smell, left behind by events and people. In a way of speaking, they can smell the future coming.