Smell is a powerful sensory capability.
It's the most evocative sense we have, the one most bound up with memory.
And we and other animals use it to do some really remarkable stuff.
All sorts of species, fish, birds, probably elephants, rely on smell to guide them on their great migrations.
For example, rats can sniff out landmines.
And yet of our various senses, smell is also the one that we tend to neglect.
We treat it as if it were a little bit primitive, sort of childish, or generally unserious, you might say.
We look down our noses at smell.
And so when a woman in Scotland realized that she could actually smell Parkinson's disease, that the illness itself gave off what was to her this intense, musty, oily odor and gave it off years before a diagnosis.
It took a little while before doctors and scientists really began to listen.
My name is Scott Sayre, and I'm a contributor to the New York Times magazine.
For a recent piece, I spent a bunch of time with Joy Milne, a scottish retiree with a really extraordinary nose.
And you'll hear about her in this week's Sunday read.
Joy's always been a hyperosmic, or what's maybe better known as a super smeller.
She actually makes serious adaptations to her life.
In order to avoid certain scents, she'll only drink water that comes from a spring, for instance.
She changes sidewalks to avoid the stink of men's spray deodorant, which she particularly detests.
So one day, many years ago, Joy caught a whiff of something new on her husband, a peculiar, unpleasant scent, something stale and thick.
It was only much later, years after hed been diagnosed with Parkinsons, that she realized that everyone else she met with Parkinsons smelled exactly the same as he did.
When Joy first told scientists about this bizarre realization, not too many of them took her seriously.