Every other Friday, the Outside/In team answers one listener question about the natural world.
This week, Jenna from North Carolina had a question about pheromones. She asked, "Do ideal mates really smell better to us as humans than non-ideal mates?"
Outside/In’s Felix Poon and Nate Hegyi looked into it.
Transcript
This has been edited for length and clarity.
Felix Poon: Nate do you get the same Instagram ads I do for cologne that’s supposed to make me irresistible to the ladies?
Nate Hegyi: No, no that’s so fascinating. What kind of algorithm are you churning up?
Felix Poon: I don’t know, pheromone algorithms.
Nate Hegyi: Evidently.
Felix Poon: So, I followed my nose to Tristram Wyatt, he’s a zoologist at the University of Oxford. And I asked him, first of all, what the heck even is a pheromone?
Tristram Wyatt: So a pheromone is a molecule or combination of molecules that's the same in every male of a species or every female.
Felix Poon: So it’s basically a universal smell that’s supposed to elicit some universal response. And it’s been a lot easier to find in all sorts of animals and insects. The first one to be found was in silk moths in 1959.
Tristram Wyatt: A team had to collect the pheromone glands, the bits of tissue that produce the pheromones, from half a million moths.
Nate Hegyi: That sounds like a really tedious job.
Felix Poon: Yeah, they literally had to snip off the abdomens of half a million female moths and then isolate a molecule that, on its own, could attract male moths. This is actually something that’s used in pest control now, to basically divert moths instead of killing them.
Nate Hegyi: Okay so that’s moths, but what about pheromones in humans?
Felix Poon: Yeah it didn’t take long for scientists to go looking for sex pheromones in humans. And there was this famous study in the 1990s where a Swiss scientist tried testing for this in college students.
Tristram Wyatt: He got the male students to wear a t-shirt overnight, and then he had the female students sniff the t-shirt and rate it for whether they were attracted to the smell.
Felix Poon: And what he found was that the women preferred the t-shirts that were worn by men who were more genetically different from them.
Nate Hegyi: Well I guess that kind of makes sense because if you’ve got an older brother and you smell his t-shirt you’re like, ugh.
Felix Poon: Yeah, but it’s not really conclusive unless you isolate the specific molecule of attraction, like they did with the moths. Now there is one company that claimed to have found human sex pheromones in the 1990s. The one for males they said is called androstadienone, and the one for females they said is called estratetraenol.
Nate Hegyi: So these are the Instagram ads you’re getting now, it's from companies like this.
Felix Poon: Exactly. They infuse infused perfumes and colognes with these things. But, Tristram says there isn’t any evidence that these qualify as pheromones because they don’t elicit a universal response. The problem with trying to find human pheromones is that courtship is really complicated in humans. You know, there's personality, values, sense of humor. Which isn’t to say that smelling nice doesn’t affect attraction. I mean there are lots of studies on this and it definitely does have an impact. It’s just what smells nice to one person might smell stinky to another depending on say your culture or you know very subjective things.
Nate Hegyi: Right.
Felix Poon: But, Tristram’s still hopeful we’ll find human pheromones. A research team in France demonstrated that newborn babies will turn towards the smell of breast milk, and the breast milk doesn’t even have to be from their own mother. If they ever isolate the specific molecule that gets them to do that, then it would technically be the first pheromone discovered among humans. And…
Tristram Wyatt: Then that would give us much more confidence to put the hard work of looking for a human sex pheromone.
If you’d like to submit a question to the Outside/In team, you can record it as a voice memo on your smartphone and send it to outsidein@nhpr.org. You can also leave a message on our hotline, 1-844-GO-OTTER.
