It is said that during mass migrations birds rely on three senses. Firstly, they hold a mental map of the terrain from a high vantage point, and thus can visually guide themselves on.
Secondly, a sixth sense seems to use the earth’s magnetic field, or rather the fluctuations in it, to keep a sense of location during flight.
Thirdly, birds have been proven to associate certain smells with their home region. Aromas drifting for miles high up at the level of bird flight can be detected by these creatures. The identification of the scent- it could be of the sea-coast, or of an industrial landscape, and a judgement of the prevailing wind direction, can help the bird home in on home.
I have this painting on the wall at home (not the original of course!) and it’s always puzzled me. Salavador Dali had some kind of obsession with Noses and lips (check out the perfume bottle) but in this case the obsession seems to be with mushrooms- and psychedelic ones at that. Maybe that’s where Senor Dali got his inspiration
“I was conscious of a faint smell of the scent known as white jessamine.
There are seventy-five perfumes, which it is very necessary that a criminal expert should be able to distinguish from each other, and cases have more than once within my own experience depended upon their prompt recognition.”
“Hound of the Baskervilles” October 1889 Sir Arthur Conan Doyle
Lucky Sherlock- only seventy five perfume brands to consider. Now there are over 6000 fine fragrances and numerous other knock offs/mass market brands to work on.