Relax. Close your eyes and inhale deeply from your nose. What can you smell? The pleasant feeling of light, volatile odour molecules floating into the nasal passage and hitting your smell receptors is an intriguing experience. This experience could cover a much wider range than previously thought as scientists have discovered that our sniffing powers can detect more than a trillion odours.
Published in the journal Science, the paper found that the human sense of smell can detect more than 1 trillion odours, opposed to previous studies indicating a 10,000 odour radius. The human’s selection of senses in taste, hearing, touch, sight and smell are remarkable factors in our genetic make-up and the recent findings take our sense of smell onto a whole new level. Initial research suggested that our sense of smell may have never played much purpose, however the new findings show that the human smell receptors are as important as those in many animals.
Dr Leslie Vosshall, author at the Rockefeller University said: “Humans still have a sense of smell. We are just unaware of how good we are at smelling and are unlikely to use these senses to our full potential. Our paper shows that humans have a dramatically better sense of smell than previously assumed. It’s there for us to use. Everyone should go outside and smell things and be more engaged with scents.”
The modern day human holds their nose high above the ground and away from the majority of odours lingering on ground level. Dr Keller suggests that our ancestors made much better use of their sense of smell and that the purpose of the nose had larger importance. He said: “This could explain our attitude that smell is unimportant, compared to hearing and vision.”
Personal hygiene has also played a major effect in the evolution of the nose; by having daily showers it has effectively cut out a lot of the odour encounters that were once valued by our forebears. Nevertheless, the development of new food combinations and mixtures of ingredients in cooking has presented us with a constant supply of never experienced before smells and senses.
The study took place with volunteers smelling vials of odours that held different mixes of 128 odour molecules from orange to spearmint. They were then presented with three vials at a time, two of which contained identical mixtures of odour molecules, with the third one being different.
After being asked to pick the odd one out, the volunteers on average could distinguish between mixtures that shared as much as 51% of the same components.
Our nose receptors play an important role in daily life for both smell and taste. There are even specific smells that are enriched by human nose receptors- if you are looking for a nasal treat then look no further than zesty fruits and mint! Studies in 2010 found that the smell of lime is biologically hardwired to be pleasant for humans.
Oranges and grapefruits were also amongst the list of enjoyable smells. There is also supporting evidence as to the pleasures of having flowers in a room or nearby. The perfect gift of course- the chemicals and molecules commonly found in flowers such as freesia, amyl acetate and mimosa are likely to be universally liked.
What is your favourite smell and what season is the smell most prominent?