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The Nose Really Does Know, It Turns Out…

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Photo credit: MarionF via Pixabay.

Anthropologist Sarah Ives reflects on the experiences of people whose sense of smell fell victim to COVID-19:

Melissa, a New York–based podcaster, realized how crucial scent is for safety when she lost her sense of smell. “I kept burning stuff on the stove,” she says. “I’ve sent rotten turkey to school with my kid. I have thought, What if I end up dying because I can’t smell something dangerous, like knowing whether you are going to burn the house down? I’ve literally almost done it three times. There are flames, and I’m just sitting in the other room.”

SARAH IVES, “WHAT THE ANTHROPOLOGY OF SMELL REVEALS ABOUT HUMANITY” AT SAPIENS (JUNE 30, 2022)

Anosmia, the loss of a sense of smell, affects up to 80 percent of COVID sufferers. It is usually temporary but, however long it lasts, it is a health and safety concern. Science journalist Gaia Remerowski reports a similar experience:

One year, my dad came down with a terrible cold and a very high fever. As with many colds he’d had before, he lost his sense of smell. But this time, it didn’t come back.

By Christmas that year, we were all gathered in the kitchen as my dad cooked a big family dinner. My cousin, who was standing near the stove, said she smelled gas. It turned out one of the burners was no longer lit and gas was escaping quickly through the house. My dad, who had been at the stove the entire time, couldn’t smell it at all.

Ives, author of Steeped in Heritage: The Racial Politics of South African Rooibos Tea (2017), notes that the human sense of smell is far more sensitive than we may think:

While many people can discriminate between several million colors and nearly half a million different auditory tones, we can smell more than a trillion odors.

Smell “has this infinite dimensionality,” says Matthew Cobb, an evolutionary neurobiologist at the University of Manchester. Yet smell remains distinctly enigmatic, he adds. “We understand how vision works, how hearing works, and more or less how taste works, how touch works, but not smell. We don’t know what the rules are.” 

SARAH IVES, “WHAT THE ANTHROPOLOGY OF SMELL REVEALS ABOUT HUMANITY” AT SAPIENS (JUNE 30, 2022)

Rutgers University neuroscientist John McGann reports

“The fact is the sense of smell is just as good in humans as in other mammals, like rodents and dogs.” Humans can discriminate maybe one trillion different odors, he says, which is far more, than the claim by “folk wisdom and poorly sourced introductory psychology textbooks,” that insist humans could only detect about 10,000 different odors…

“Dogs may be better than humans at discriminating the urines on a fire hydrant and humans may be better than dogs at discriminating the odors of fine wine, but few such comparisons have actual experimental support,” McGann writes in Science.

The idea that humans don’t have the same sense of smell abilities as animals flourished over the years based on some genetic studies which discovered that rats and mice have genes for about 1000 different kinds of receptors that are activated by odors, compared to humans, who only have about 400. 

RUTGERS UNIVERSITY, “THE HUMAN SENSE OF SMELL: IT’S STRONGER THAN WE THINK” AT SCIENCE DAILY (MAY 11, 2017); THE PAPER REQUIRES A FEE OR SUBSCRIPTION.

In direct comparisons, humans sometimes do better than other tested mammals, says Linköping University biologist Matthias Laska, who has studied the question for two decades.

Read the rest at Mind Matters News, published by Discovery Institute’s Bradley Center for Natural and Artificial Intelligence.