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Introducing Unexplainable

2021-03-14 | 🔗

Unexplainable is a new podcast from Vox about everything we don’t know. Each week, the team look at the most fascinating unanswered questions in science and the mind-bending ways scientists are trying to answer them. New episodes drop every Wednesday. 

Learn more: vox.com/unexplainable 

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This is an unofficial transcript meant for reference. Accuracy is not guaranteed.
Hey it's Matt. Today's episode is gonna, be a bit different instead of the weeds you're going to hear an episode of a new podcast from my friends in box is called unexplainable. Unexplainable is all about the most fascinating mysteries in science. Each week the team will dive into one scientific question that remains unanswered, talk to scientists and experts about how they try to find answers to these questions, the shows hosted by NOME Hassenfeld, it's gonna future reporting from producer Bird Pinkerton Box science reporter brand resnic. It's a great team at this episode is all about the nose. We know the basic mechanical of how smell works, but we ultimately don't know why one substance smells one way while another smells different known. Mixed. One researcher was built a robot knows they could smell even more accurately than a dog to see. If he's gotten any closer to answering this question other episodes dig into everything from what really lies at the center of the earth to why mysterious balls of lightning have been recorded throughout history. Talking about what we don't know can be uncomfortable, but right now it's more important than
ever before should enjoy a weekly deep dies into the weeds on policy. I think you will like this show you follow unexplainable in your favour, podcast apt to get new episodes every Wednesday morning This is unexplainable, I'm I'm having felt hang out here with our senior signs. Rapporteur, Brian Resnick, hey. So this is a show about unanswered scientific questions. Brian. I wanted to talk to you because, when we were initially talking about topics we might want to cover on the show you you told me there is this mystery. You wanted me to look into about the nose yeah I haven't done. Research on this myself but Edward. I do remember seeing a Youtube video that it was going on about
like how smell is still a mystery. Yet we still don't know everything about how smell works and it's kind of shocking, because it's a pretty basic thing do not fully understand. Yes, like one of the five senses, you learn an elementary school. Yet, as I looked into this over the last couple weeks, I realize this isn't just a fun mystery solve. If, if we could solve this mystery, we could actually save lives because cancer has a smell. I've never smelt it. Well, we can't smell it, but dogs can I'm sitting here with actually for I detection dogs, I talked to a scientist. Shoes are particularly big dog fan, Doktor Clare Guest, if you hidden in the background, is because they ve been for a nice long walk They are commonly drawing an scratching their paws on the carpet, though some cute, so in the early two thousands Clare was train
the dog, her bio detection dogs, so that they could smell disease. But then her work took a turn. She was training, her dogs, for a big upcoming study and one of my dogs, a beautiful dog who live with me called daisy. He's a fox read Labrador, she started to look upset. That was probably the best description a bit upset by me. She was just kind of sitting there just staring at me and then nudging at me and staring at me and nudging at me. Clara felt the spot where Daisy was nudging and she could fill a lump and I ass he went on to be diagnosed with a very, very deep, seated early stage
cancer. She got it treated and luckily she's okay, but she might not have found it in time, because the tumor was actually very defeated if it wasn't for her dog, daisy wow. So like Daisy, she was trained to do this yeah yeah, so it's sort of like a game, so you teach them to recognize an odor when they sniff that new disease, they say whoa. So that's interesting! That's what you capture you, give the dog a reward. The dog starts to realize you want me to find this characters to go to, and then you build from there once the dog learns. The smell Claire can use a bunch of different things, urine sweat, even pieces of socks, worn by people with a certain condition. She takes some positive sample,
and some negative samples and she puts each one on a stand: okay, they're sort of slotted into a grill on the stand and the dog goes along the grill sniffing each in turn. If the dog smells a positive sample, he'll stop and wait for a reward. If it's a negative sample, he moves from the one sample to the neck, so the passing on means it's a negative chief sample says cancer, though my thing maidens mouth smell can maybe smell other diseases. Oh it's not just cancer. It would seem from the docks behaviour that every single disease and condition has a unique Oda and dogs can be trained to reliably. Finally, and tell us about it. How me what diseases we we talking about can basically detect everything we ve tried so far, so they ve done various forms of cancer bladder cancer, prostate cancer and breast cancer
Parkinson's, vicarious malaria and when I think might be the most exciting part of this whole research is that now they're, starting to test disability uncovered Reich really like dogs can smell people who are carrying the current of ours yet, and they can do a pretty good job actually Clare as the research is looking really promising, they should be publishing the result soon and just think about the potential here I mean it's so much quicker unless invasive than your average. So in your nose, pc artist. This is with a single sniff. Sniff takes the dog about half a second you could just have a dog smelling tons of people in and send the ones that the dog thinks have covered for a pcr to confront so like what do you want here illegally enormous dog army. That would be one way and in some places are actually doing that there have been covered sniffing dogs in airports in Helsinki here, in Helsinki thereof,
of the pack into by now the folks in the Emirates claim they have train dogs to detect the smell of corona virus. With a ninety two percent success rate they were even used to screen, fan that went to Miami HEAT Basketball, game. Carbon sniffing dogs will now great fans before they enter the arena, but idea of seriously scaling all this up. It would be really tough to manage. It would take at a time and money and expertise the training easy and, aside from being difficult, a dog army has never been the plan here. The idea, as always been for the dog to translate, for he knows with his nose to an electronic device, and if scientists can reverse engineer what's going on in a dogs knows they could use a robot knows you know, maybe not for this pandemic, but for the next one. That would be helpful, but this is where the whole mystery of smell, starts to be a big problem and that sort of
when a focus on for the rest of the episode, because we don't really understand how smelt works her. We got some of the basic mechanics down but the fundamental issue is that we don't really know why one thing smells one way and my other things smell a different way than you would need to know that yeah. And how can you
harness the power of dogs knows if you dont know how smell works, but it's not like. We can't be totally in the dark here right, you did say we know some basics of how odor works. Yet we know the basics. So what is basically why? What is smell so their stuff, all over the place? Imagine like a candy bar or a tree or a candle. Anything and molecules these, like small bits of staff, are kind of flaking off in bouncing around and smell is actually kind of like touch or taste it. Its physical you're actually touching these substances with inside of your nose. You us smelling materials that reach a news and that physically directly material interact with it. We set this in your news that ends
the bar which she's professor at Indiana University? So when you go to public toilet anything or somebody went there before me, it's not shitty. Well, you ve got figure molecules indeed actually reaching an early, so I'm ruining a lot of experiences, so we ve got molecules hitting receptor proteins in the back of your nose in your brain, make sense of it all as a smell. That's the simple part. The tricky part is, even though we know how, as now into the knows. We don't really know why things smell the way they do. For a long time. The best thing we can come up with was the shape of the molecules, so lake, Sir, molecules if they have a certain shape? They smell one way and if they were configure differently, if they had a different shape, they would smile differently the exam? we did. This is called the lock and key model. Basically, there are a lot of different receptors in your nose lots of molecules out in the world and it sort of like
its game. You know you put the triangle in the triangle home, but the but the square into the square hole and just to be clear. So the receptors here are the locks, and these molecules are the keys that were right get unlocked and those send smell signals to your brain, but the more we studied receptors, especially in the last few decades. More, we realised that they can really work like locks with keys, first of all, the math just doesn't work we have in humans about four hundred. Does we ve got potentially trillion Oda molecules that humans can respond to so clearly, it can't be just a molecule receptor interaction can smell one trillion different things, yet one trillion different things and there are definitely not a trillion different types of locks and you're, not there's only four hundred. So the idea that you might have certain shapes of certain molecules responsible for certain qualities. Wasn't a naive
then you know the more were learning about these receptors. They start to look even less like locks, because scientists have discovered that receptors actually can like change their shape. These are not rigid entities because their concentration in confirmation of this quickly and wiggly- and they move a lot and the lock and key looks so intuitive it looks, but this is just not how it works so works. This idea, like completely bank like smell, has nothing to do with the shape of the molecules well, scientists think that shape is like one factor of many, because, like molecules that have similar shapes can smell, different molecules that have different shapes can smell exactly the same. What you're saying? here is that if I drew a picture of a molecule and took it to a scientist, they wouldn't necessarily be able to tell me what that molecule smells like right. There's a few molecules that might work for, but there's no systematic way to predict
smell, just based on the shape. Essentially, the lock and key model might sound nice, but smell is just a lot more complicated and actually dynamic. You have like a tango almost going on, so sometimes you might have a dance partner and you've got this kind of erotic tension other times the feeling isn't there and others you think a place. I never never again. Attraction is complicated, So it is a similar way receptors of different sensitivities, and each receptor is attracted to different kinds of things, so you might have one receptor that goes. You know I totally be out, for. I go for that. Another might be into a molecule when a kind of ring shape how the molecule is how flexible can be looking for more than one thing, and the next one might actually have ten different features. The reason it's a dance, though, is because these two
partners they do more than just fit together. I like the analogy of tango, because you've got two people do to get interacting and you've got sometimes, of course, a more dominant person that bleeds, the other. Sometimes the receptor can take over. So the receptor might also bend the molecule if it's a bit more flexible other times. A molecule can activate a receptor turning it on, but in a different molecular contact. A different mixture. It decreases receptor activity which is more of a turn off in all of this is happening four hundred times over for each receptor in the nose and then getting sentiment brain. How does the brain knew what feature this reset? The response to we don't really know. That's the interest in question So the nose is really complex and sold on that it is. It sounds to me like we just have no idea what this dance looks like for every conceivable odor and that's it.
Oh here, well, that's part of it. What goes on in your noses is definitely super. Complicated in this dance is what allows four hundred receptor is to create a trillion different smells, but that there is actually a second level here. Different people can smell the exact same thing and experience different smells. Like think about salon. True, I'm sure you know how some people think it smells and tastes like. So I came to think it tastes like soap and smells like soap. Oh now, that's sad, but I also don't hate it s weird, but I guess my nose just doing a different dance than your nose. Yet that's, basically it and it's because you're a mutant. Actually, oh, if salon Trow smells like soap to you, it's because you have a mutation that causes your receptors to respond differently well, but on top of all this,
there's a whole bunch of things to consider that has more to do with the brain things like language and culture. What your mom ate when you were in the womb context experience all of these things, impact how you smell- okay, but here's where we get to the truly bunkers part scientists are looking at all of this. The whole tango and they are undeterred, because the idea dear of harnessing this superpower in the dogs knows to smell disease it it's so enticing that some scientists are just full steam ahead on up nation build a robot knows so those people now have now works, not we know how Can you build something like a robot knows when you just don't know stand how smell works there. Just of ignoring the problem. Just just ignoring it yeah it turns out, you might actually be able to build a robot knows really understanding how it works.
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o Brian we're back up. So three things to remember from the first half of the show. One dogs can smell all kinds of diseases to. We don't really know how they do it because smell is this super complicated knows NGO that we don't really understand, you got that one in three. Despite this enormous question mark some people are still trying to make a robot knows there. There actually excited by how little we know what a trap into the whole game a smell. Was these dogs being able to something that's no analytical tool in my lab could do. This is Andres Merchan he's an excitable research scientist at MIT and I have access over a hundred million dollars worth of equipment, and it kind of pisses me use that a lowly dog can do better than a hundred million dollars worth of equipment. Some things off with that picture. I should be able to do this, and all this big fancy equipment has can do this whole thing because of this complicated
tango, that's going on yeah how the nose tango exactly works. We still this big question mark, but Andreas thought he could solve it. I just decided to look. The Dutch have proven that they can do this. We can do it to figure out, and fortunately, Andreas got a great chance to figure it out, DARPA the research and development agency for the Defense Department. They wanted to figure out this dog superpower to maybe use it to sniff out bombs, other things, so they held a contest to see. If someone could build a robot knows the goal was pretty simple: beating the dog that was a challenge. It was an mit scientist up against a dog Andreas liked, his chances. I thought I knew what I was doing outbreak evident. He got to work the collaborator at MIT. She, one John who had figured out how to grow real receptors in cells. The same receptors that you haven't knows we established
them using various technologies and they sort of spreading out on top of a circuit board? It looked about the size of a desktop, maybe laying sideways wait. A minute. Please you talk like this is a cyborg. Like something out of science fiction yeah. This could be like a cyborgs knows or something tat. He thought that it could sort of work like a soup up carbon monoxide detector, just one that would look for certain bomb related chemicals if it detected All of its kind of chemical alarms would go off, but there were so many chemicals it had attacked the alarms just what had gone off way too often. Essentially, he realized this model just wouldn't be able to decode the nose tango. So he is right back beginning square. One now like he thought he could solve this whole tango sniffing bang and just failed yeah, but it actually gave him an idea. He thought he had to build something that decodes smell.
You know that figures out exactly what it is based on its tiniest parts, but maybe that's not how smell works. Andreas kept thinking about Clare and her dog daisy, he was thinking, wait. Daisy. The dog of Clare was trained on bladder cancer does this at the breast cancer, which is really weird, because the tell tale molecules of those two types of cancer are different: there's nothing in common to them, and yet the dogs can generalised d, on one cancer? They realize all this also smells category have no idea how the dogs can do this. We just know that they can serve as a kind of like their their learning. What cancer smells like yeah that that's what I thought You're teaching the dog had to smoke answer. Maybe when you smell something, you don't see a list of molecules same as when you listen to music. If you look at a painting, you don't see a list of pixels and color values. You see the whole painting at the same time, so this India is, is really key.
Actually want to use one of Andreas as examples and try to think about a smell like a piece of music Brian you recognize this song right. Obviously, no it because you recognise the pattern, you don't Sisera. We know it because you ve memorized every last individual sound, but also, I know what the sounds. Won't you so recognize it. When the sounds change like, if I play it with a synthesizer we're a trash can or even when it's an indifferent key
Actual notes are different. You can recognize it. You still recognize it yeah, it's still somewhere over the rainbow right, even though the parts are different, the relationship between the parts is the same, but the pattern is the same. So smells are like these big holistic patterns. We learn to recognize yeah. It's like you just need that kind of whole impression. So here's where we get to robot knows two zero. He called it. Banano knows the yeah, and this time he tried something different. You realize he didn't need a chemical detector. What he needed was a brain. He looked at them couple of a dog and he said, look we're not the dogs are doing this. All we know is that they can do it and that they can be trained. So if Andrea's could build something that recognizes a song not the individual notes themselves, but a bigger picture, the pattern he wouldn't need to.
You're out exactly how all those parts come together to form a smell as long as he could train it like a dog, it could work so Ike How do you train cyborg? Do you give it a treat honestly kind of? Let me the idea so simple, it's either super brilliant or world very crazy in and then stupid, because here's what we thought- okay, we gotta, get weed, understand what the dog thinks about. We do now how the dogs knows ultimately works, but if we follow the training that the dog is having meaning dog gets a reward when it smells the right stock, the computer, it's slightly different instead of a reward, it's a different button. You push and it just informs all the receptors at that point. Whatever you sniffing now is the thing we're looking for, find other ways to find that same thing. This is kind of like machine learning like building up artificial intelligence yeah, instead of
Solving this enormous mysterious question mark of exactly how smell works. You know how every little part comes together to form a smell Andreas just ignored the question: where is he the man who knows to recognise patterns showed it what it needed to recognised for the test and then he let the NATO knows teach itself had a recognised the smells and when you reach the same statistical here, one involving dogs, one involving machines. At that point, you can basically say of either the two things are doing the same thing to the limit of man. So undressed ignored. The question mark instil built a working notes. What what's gonna score? here is that what's going on in the narrow knows it might not be the Acting that's going on in the dogs had Andrea's doesn't really know. He just knows that it works and it does work like he built this.
Well sort of Andreas showed that it could smell certain molecules that DARPA was interested in and it's pretty sensitive, but that was in an extremely controlled setting, which might Why DARPA ultimately moved on from the programme The real world is just way harder. There's all these smells bouncing around, but Andrea thanks banana knows can still get there. He still pushing forward with the research and ready he's working on making the brain part way. Smarter. Oh so, like this dismay, I just need to get better yet are still trying to first engineer exactly what's going on and dogs had when it smelling like what exactly make something smell: cancer, Andreas and Clear actually just put out some really promising research on that front last month, but they haven't put it all, together with NATO, knows in a real world environment. Yet, yes, how do you like getting ready for the real world is not easy? He's gonna have to expose it two tons and tons
smiles to keep training the brain make the a I smarter and that could take a while, but as far as the actual NATO news itself, you got no way smaller than a desktop. Now, at this point I can actually fit inside your phone. Is that the goal here am I gonna ass, like hey SIRI, do I need a shower? Maybe I do. About Syria, but I can tell you that for Andrea, that is absolutely the next step. Think about it, right. Any single one of us can have a mole that becomes malignant and it has a this period of six months. It's changing, color is changing, shape and exchanging small. If you wait six months, sometimes it becomes a death sentence, and this isn't some sort of far off cipher technology. This could be happening soon. I think we're maybe five years away, maybe a little bit less to get it from where it is now. Two full inside of a phone and I'm talking to deploy into a hundred million false medical device. Phones are coming, there's still some
like this. It's not solved here like we might get noses and our phones, but still he don't know her nose works yeah. It's kind of weird, but here What might actually be my favorite part of the whole thing, it's true that he skipped over understanding. But what I love about this is that this move this. This skip might be the exact thing that ultimately get him to the understanding Richard Feynman, a famous physicist, he famously Mps blackboard they died. What was left on that was, if you cannot create something, you don't understand it Kind of deep and powerful by then realize that it put it really meant was its folly to think that you must unjust. Something before you build it. That only works. If you already know it, maybe What fine men was actually saying, was more like this builded to understand it but you can understand something better through the act of building the Wright Brothers who invented flight, they didn't know
work. They build their plan in order to understand how it will fly. So this is what happened with us with the nose anything. Is here the scientists don't perfectly understand how planes lie yet probably for another episode, Yellow get to it: as far as the nose. Andrea still doesn't have the complete picture here, but he's closer, and he's learning more. The more work that he does to build it to understand it, but TAT understanding part not quite there yet, kind of love this as an answer to an unexplainable question, because you know it shows, you don't need The full answer to actually make progress here. We have this incredible. Sounding new technology yet, and I, I love this sort of confidence and hopeful ass, an optimism of Andreas Exam but because he is honest, the fact that he doesn't really know how the nose works, but that big, empty box that question mark
is starting to feel less like an obstacle and more like an opportunity. This episode was reported and produced by no on passing out. He wrote the music fourteen editing from a giant Mr Ryan Resnick and me bird Pinkerton Lily Mitchell Lena did the backtracking, Hennis Brown did the mixing and sound design things Hennis and Meredith hot? Not is our senior producer also Liz Kelly Nelson? Is the editorial director of Box POD Cas special extra thanks this episode to Sarah Harrison and two Ella fatter?
Also the mystery of smell has some pretty wild turns that we couldn't fit into this. One episode like there's this theory that the way our noses really work is by using quantum mechanics which gets a little complicated. But if you want to dive really deep, please check out our show notes for a link to a peace by an, Sophie bar, which you heard from her in the first half of the show, and she wrote all about how the scientifically Ve got really enamoured with this quantum knows theory, and then the theory wasn't really all that it was cracked up to be, and while you are down there in the notes, we ve got a link to the unexplainable website. Where you can find articles about our episodes show transcripts. You can find more and make sure to jog down or email address, so you can send us your thoughts year at unexplainable at box. Dot com. Please send us, that's, we would love to hear them.
One more thing: if you want to learn more about the mystery of smell, I cannot recommend enough and book smell atrophy. It covers all kinds of fascinating history that we were unable to get into this episode. Unexplainable is part of the box media podcast network, and we will be back in your feed next Wednesday.
Transcript generated on 2021-05-06.