The Melanie Avalon Biohacking Podcast Episode #201 - Jackie Higgins

TRANSCRIPT

Melanie Avalon: Hi, friends. Welcome back to the show. I am so incredibly excited about the conversation that I am about to have. The backstory on today's conversation, there are a lot of different ways that I book guests for this show. Sometimes their publicists or their agents will reach out to me, sometimes it's through a friend, sometimes I directly reach out, sometimes publishing houses will send me a catalog of the books that they're working with or representing at that moment and ask if I want to interview any of those authors. I got one of those emails a while ago now, and I was looking through all of the books on the list and one immediately jumped out at me. It was called Sentient: How Animals Illuminate the Wonder of Our Human Senses. I saw the cover and I was like, "I'm in." I didn't even have to research it. I was like, "I have got to read this book. I have got to do this interview."

I booked it, no pun intended, got the book, read it, and it was, oh my goodness, friends, everything I was hoping it would be and more. I was already historically-- I don't know, I think about our senses a lot. I have historically-- it's just hard to know with reality what reality actually is. And I've thought about how our brain can make up stories about things. I've always been a little bit incredulous about how we're perceiving the world, and then on top of that, wondering if there were more things we could be perceiving. And reading this book by Jackie Higgins, she goes into the animal kingdom and talks about all of these incredible senses in different animals and what we can learn from that, how it applies to humans and it was really, again no pun intended, eye-opening experience. I feel like this is just ripe for puns.

Jackie Higgins: It's difficult to avoid the puns.

Melanie Avalon: I know. I feel like everything I say is going to be a pun. But in any case, I have so many questions and I cannot wait for this conversation. So, Jackie, thank you so much for being here.

Jackie Higgins: Wow, Melanie, thank you for having me on and thank you for such, it's lovely to hear the backstory of how it all came to be. And I'm really delighted you enjoyed the book. That gives me a warm glow. [laughs] Some sense.

Melanie Avalon: Honestly, I do love all the books that I have on because it's something I really want to read about. But yours was one of the books where I just had fun, like, so much fun reading it, and while learning a lot.

Jackie Higgins: That's really great to hear. I mean, before becoming a writer, I used to make documentaries, wildlife films, and science documentaries. And my job has always been to try and tell stories that aren't told because often they're normally found in dusty scientific journals. Translating them and making them fun, if you say they're fun, then I've succeeded. That's great.

Melanie Avalon: You definitely did. I definitely had that commentary in my head of just how much I was enjoying it. Well, you just touched on it a little bit right now. But for listeners who are not familiar with your work, I would love to hear a little bit about your backstory. You have appeared on numerous outlets, National Geographic, PBS, NOVA, Discovery Channel, like you mentioned making documentaries, you worked with the BBC and now writing books.

Jackie Higgins: You said it appeared. But I was always behind the camera, so I've always been a director or a producer or a researcher for these documentaries. Actually, writing a book was much more of a personal endeavor. But the way that I've structured the chapters was very much couched in what I know about telling stories with a camera lens, how to tell stories. When we worked, I worked for a long time at the BBC making documentaries, for example, on Horizon documentaries, which are like NOVA. And we're taught how to tell stories about science that would engage people.

And before that, I used to make wildlife films, and before that I did a degree in zoology. And Richard Dawkins was my tutor at Oxford many years ago. He actually the first-- I hadn't spoken to him in a long time, and I sent him this book when it was finished, and he read it and enjoyed it and wrote me a blurb, actually, which was wonderful.

So, yeah, I've always been interested in wildlife since I was a little girl poodling around in rock pools in Cornwall, and specifically, I suppose, in what wildlife can teach us about ourselves. I grew up reading books like Desmond Morris' The Naked Ape, which I don't think many people know about, but it informed the way I view the world. I'm interested in biology and the animal kingdom in order to understand myself a bit better.

Melanie Avalon: I love this so much, actually, my background. Well, I went to film school, so that's the reason actually I love this show, it's because I feel like it combines similar to you, like my love of research and learning and everything with a more approachable format for people to experience it.

Jackie Higgins: It's not until you explain something, I think, that you understand it. I mean, sometimes you think you understand it, but then being forced to either make a film about it or write it out, I think, actually really distills your thoughts and it helps you understand something.

Melanie Avalon: Yeah, actually, to that point, because one of the questions I was wondering-- so when you decided to write this book because there are so many animals, so many senses, we can talk about that, how did you decide which animals to use? And in that experience, did you have that experience that you just mentioned, where you learned while crystallizing it in the book? Did you learn more by doing that?

Jackie Higgins: Totally. I mean, for every animal that I chose, the conceit of the book is that one animal will teach us about one sense. And as I'm sure we're about to find out, the idea is that Aristotle got it wrong, [laughs] so it feels a bit mean, hundreds of years later saying this. But essentially, we have more than five senses. So, there are more than five chapters in the book. And I took an animal. It was great fun trying to figure out which animal was going to tell the story, for example, of our color vision, or tell the story, for example, of our sense of balance. But that took time. And I also wanted a balance within the book. Insects and mammals and so butterflies and octopuses and cheetahs and wonderful creatures known as star-nosed moles. That was all part of the fun, figuring out who would tell the story.

Melanie Avalon: This also felt like a film a little bit in that you went unexpected places. Like with the colors, for example. You talk about these certain type of shrimp, but you don't open by talking about their color vision. You open up by talking about how fast they are or how they can attack things really fast.

Jackie Higgins: Yeah, they've got the most fastest punch in the animal kingdom or some extraordinary thing that scientists at Berkeley University have actually studied and have numbers to put on, figures to put against the punch. Yes. So, it is part of that storytelling technique. Almost like the book, the chapter is divided into scenes and each scene propels you through to the next scene. You meet someone you understand why this person's interested in the shrimp.

You meet someone in an island in the Pacific, at the island of Pingelap where people can't see color. So, I end up juxtaposing these stories that you might not have thought would go together. And one of the fun things, actually, I remember I was trying to figure out who was going to tell my story of taste and I ended up deciding on the catfish, the Goliath catfish because I had to choose the biggest catfish or one of the biggest catfish. The scientist Professor Linda Bartoshuk, whose story of supertasters in humans has been told time and time again loved the telling of her story in Sentient because it juxtaposed her against a catfish. It is in the juxtaposition and the surprise of the stories that I guess an arc and narrative come through, I hope, in an interesting way.

Melanie Avalon: No, it definitely did. And there are a lot of cliffhangers like, you talk about the spiders that building their webs and rebuilding their webs every night. And I was just like, "What is happening?" So, there're so many things.

Jackie Higgins: More scientists looking at creatures that we'd never-- we probably don't notice them when we pass them in the woods, but they go off searching for different species and can't find the species. I think they end up calling one the unicorn spider because it's so difficult to track down. And, yes, they're looking at these spiders to understand circadian rhythms. And I use these spiders to explore our sense of time, another sense that we wouldn't necessarily have included in the original kit bag of senses because it's something that's with us almost subconsciously all the time. Actually, I became fascinated by that chapter and I'm still researching it. So, I know even more about time than I did when writing this book. But yes, secrets.

So, in addition to the overt senses, the senses we feel, like the sense of pain or the sense of pleasure, the ability to see color or the ability to see in the dark. In addition to those tangible, conscious senses that we have, I also use a term I first read with Oliver Sacks, who's an author I loved, the Neurologist who wrote books like The Man Who Mistook His Wife for a Hat. I've always loved his books and he talks about secret senses. And so, I also explore our secret senses. We have these senses that collect information about the world or about our bodies. Sensing our body is also a sense and secretly informs our perception of the world subconsciously.

Melanie Avalon: I love this so much. Some questions about that. Well, first of all, I wrote down in my notes that most of us and Aristotle decided that we have five senses. Then I wrote, but now we know that we have at least 9 pus. But then I have, we might have up to 22. And then I have, well, maybe we have 33.

Jackie Higgins: 33? [laughs]. Depends on who you ask. And it depends on how you define a sense.

Melanie Avalon: How do we define a sense?

Jackie Higgins: The book's called Sentient. But how do you define Sentience? It's the same. A lot of these terms are bandied around. There's no actual definition. So, how do you define a sense? I mean if you define a sense according to a sensor, so if you imagine our body, you think of your brain in a dark VAT of your skull and it's not connected to the world. And the only way that it can collect information about what's going on beyond our skin and within our skin. The only way it can do that is using senses that collect information, be it light information or the vibration of molecules in the air, i.e., sound information or chemical information, like smells or like tastes. The only way it can do that is through these senses. So, take a touch, and touch probably for me was the most surprising sense in our skin. I mean, I've said this before, but we always look up to the stars and we're slightly dizzied by this vast expanse that we don't quite understand. Well, I now look to my skin, which, our skin is the largest sense organ that we have. And I look to our skin.

And scientists are only beginning to understand what's going on inside our skin. We know a lot about the way that we feel the topography of the world and that's through various senses, different senses that we have in our skin. And some fire when we squeeze our hand into a glove, some might fire when we're feeling something vibratory, some might fire according to temperature. So, even your sense of touch has so many different senses. Sorry, I'll get around to the point I've got off one.

But essentially, if you define sense according to the sensor, I mean, touch is very many different senses. It then becomes too unmanageable. So, I didn't in my book, I defined it instead more broadly according to perception. So, I split sense touch into two senses. I use the star-nosed mole to explore the way that our fingers feel the world. So, the topography of the world is beneath our fingertips. That's what the star nose mole can tell us about.

And then I use the vampire bat to talk about the emotional feelings of the world, the pleasures, the pains and we all know a touch is an incredibly emotionally loaded experience. And that's a very different sense from feeling the roughness of a walnut or the smoothness of a glass of water. So, yes, it depends on how you define a sense as to how many senses there are.

Melanie Avalon: I love it so much. And actually, while we're talking about touch because I did have some thoughts and questions about it, because you talk about how touch is so vital that it's basically our first sense that we have and then our last, usually to go in the end.

Jackie Higgins: Yes. I got really interested in these slow touch fibers, these sensors in our skin that scientists are really in the last few decades, only just discovering that give us a sense of the emotional content of the world I suppose. One of the scientists who I spoke to, Francis McGlone, was fascinating on this subject and he talked about the sense of touch being the first to come online. When you are a fetus inside your mother's womb, the sense of touch is one of our first senses that we have. And he talks about the swirl of the amniotic fluid around the baby's skin and the baby has these little hairs on its body and that fluid enlivening these hairs. And that's basically being the very first feelings and senses of touch that we get. And he says how he took me on a journey and I take the reader on this journey in the book about how he thinks, therefore, that sense of self is essentially within this skin.

He talks about mothers endlessly caressing and cuddling their little babies and how this reinstates a sense of self. You know, the baby at some point becomes aware of what is them and what is beyond their skin. So, it's really interesting and it's a very current interesting science. I mean, when I was writing this book, in the process of writing this book, another of the scientist who I spoke to with regard to this chapter, David Julius, and I spoke to him about these little TRP sensors in our skin that enables us to feel heat and pain and the experiments that they did with vampire bats, because this is how vampire bats, they have specialized TRP sensors like the ones in our skin that enable them to detect the warmth of a vein or rather an artery pumping under the skin.

Professor Julius won the Nobel Prize for his work while I was researching this book. He won the Nobel Prize for Physiology or Medicine. It's really fascinating and current science. But also, while writing this, of course, COVID hit and speaking to Francis McGlone, he believes that this sense of touch is so important to our well-being and our mental health that the fact that no one could touch one another, that touch had become demonized during the COVID epidemic, was a real issue for him. I ended up writing a few pieces for papers over in Britain for this reason because he worried about that.

He doesn't think we fully understand how these sense are working and what they give us. And he fears that by not touching, by demonizing touch, we are depriving ourselves of something essential that humans need and crave and require. So, touch those, two chapters, I would never have imagined where those chapters led me. And it was fascinating. I love those two chapters.

Melanie Avalon: I love it so much. And it's interesting because I was thinking about it. I don't know if it's even worth doing a hierarchy or ranking senses, but I feel like touch would be the one sense like, if you lost your sense of touch survival wise, I feel like that would be the most dangerous to lose because you could get hurt and you wouldn't be able to address anything. Like, you can adapt to people being blind or deaf, but if you couldn't touch, I feel like you'd be in a really dangerous situation.

Jackie Higgins: Dangerous situation. So, back to Francis, he said I think his mother was a teacher or a nursery teacher and one day he remembered her coming back and telling him this when he was a young boy and it really left an impression. She asked the children that day which sense they would least like to lose and nearly everyone said sight. Because we're such visual creatures, we find that quite difficult. And most people then might say that it wouldn't want to be deaf and then most people, very few people would probably worry about losing taste, but a lot of people might worry about losing smell.

But apparently, there was this one little boy who said touch and that really stuck with her and it really stuck with Francis who ended up becoming a scientist studying touch. And as his work is showing, it is much more layered and much more fascinating and much more fundamental to-- I mean, take back to David Julius's work, the chap who won the Nobel Prize on his research into TRP sensors. These senses tell you whether something is cold or whether something is hot, or whether something is painfully cold or painfully hot. And our sense of pain, one of the scientists described it to me as our guardian angel and recounted stories of people who are unable to feel pain and consequently end up doing stupid things and dying young. There is a story in my book of one such case. So yes, without pain we wouldn't hold back from things that are dangerous and then without pleasure. Well, maybe the human race wouldn't have continued for obvious reasons. But yes, fundamental and we've yet to discover how fundamental.

Melanie Avalon: Is there a difference in touching something and being touched?

Jackie Higgins: Yes, absolutely. Touching something was much more the story of the star-nosed mole, touching something and feeling the topography, the ridges, the size, whereas being touched is different. And if you look at the distribution of different senses at our fingertips as opposed to in our arms or in our back or in our neck again and elsewhere on our body, there will be different senses or different concentrations of those senses in different places. So yes, being touched and touching are different.

Melanie Avalon: I was thinking about it because I was thinking then if you touch your two fingers together that's like four different signals that's each finger touching and being touched. And I was just thinking about so how is the brain interpreting that information?

Jackie Higgins: And then I guess this is the impossibility of being able to tickle yourself as part of that story too. Clearly, it's much more a story that's not just about the sensors, it's also about how the brain interprets it. So, yes, it's a tangle of interesting information.

Melanie Avalon: Yeah, because you didn't talk about tickling in the book. Do you know the purpose of tickling?

Jackie Higgins: I don't, I've read various evolutionary kind of what is the purpose of tickling? I don't know that there is an answer, but it is interesting that idea that you can't tickle yourself, it just points out the difference between information might be collected but then is reacted to differently according to whether you're the giver or receiver or both when it reaches your brain.

Melanie Avalon: I have a question about that. But before that, just talking about losing our senses, one of my defining memories from high school actually it was from our teacher who ended up becoming my favorite teacher of basically all time. One of the first questions he ever asked us in our class was "If we never had our senses to begin with, would we be aware of ourselves?" And that question haunted me, like haunted me.

Jackie Higgins: Yes. I don't think we would. I mean, golly, help. But essentially our senses, whether they're collecting information about the exterior world or the interior world, there was another really interesting chapter that I loved writing and that was the one on proprioception, this idea of sensing your body and where it is in space. And that's an interior sense. And we meet Ian Waterman-- I met Ian, who is one of the incredibly rare people who's lost their sense of body, their sense of proprioception. When he closes his eyes when he was in the hospital, after this virus had wiped out the nervous link essentially, between his proprioceptors and his brain, after that had been wiped out and he couldn't feel his body, he would close his eyes and he felt disembodied. I mean, he could feel from everything below his neck when he closed his eyes, he could not feel his body. Imagine that, so kind of the plot thickens with regard to what your teacher was asking because you are losing your body awareness if you don't have proprioception, yeah.

Melanie Avalon: Just a comment on the proprioception. That was actually one of the times I actually laughed out loud and I wasn't laughing at him. But basically, for listeners and you talk about this in the book that other parts of our brain can fill in if we have a lack. So, he was able to use vision to control his body movements, even not having proprioception. But you talk about how if he wasn't looking at his arm, for example, it would just do things, which is so interesting to think about.

Jackie Higgins: Well, he didn't know where it was and what it was doing. Like the octopus is my point. Ian is one of these exceptional people. I suppose he's being forced into this predicament with what happened to him. But the way that he reacted to the situation is immensely noble and extraordinary and brave. And when you talk to him, he jokes and makes little but he is an amazing man and he was very generous to share his story and talk about it. It is difficult to imagine what it is. You asked earlier, what is sentience? What is consciousness?

It's impossible to imagine another person's subjective experience, particularly when it's so different from your own. And I think the external senses perhaps we can get a better idea of like it's easier to imagine what it might be like to be blind. We simply have to close our eyes. But our sense of proprioception is so enmeshed in the fabric of our musculature and our bodies that you can't tease it apart. I can't imagine what it would be like to lose this sense. So, Ian tried to explain it to me and I think he did brilliantly.

His effort in order to regain control of his body, given he'd lost this sense, as you said, to use his vision to basically take over where proprioception had left off. And he has to watch and he had to reteach himself. He had to break down every motion and he had to then watch as he rebuilds it in real time in order that he could peel his back off the hospital bed, and could sit up, and could reach for a glass of water. And now when you see him today, he's doing all these things, and you wouldn't notice there was anything amiss. But if the lights go out, he says he crumples like a Ragdoll.

Melanie Avalon: I know it's not even remotely the same thing, but the closest thing I could think of would maybe be when you're looking in a mirror and everything's backwards and you're trying to move accordingly, you have to tell yourself how to move because it's backwards in the mirror.

Jackie Higgins: I suppose that introduces an element of confusion between you and your body. It's not an element of loss, but it is an element of confusion trying to figure out. I know what you mean and I get confused by that, too, even having made documentaries and camera right, camera left, or having written about photography, and I've written books on art photographs, and yes, I'm still confused by that. Perhaps that's just a problem with my left and my right.

Melanie Avalon: Well, speaking of imagining senses and also left and right, it's also probably hard for us to imagine having senses that we might have, but might not be as intense or strong as they could be. So, the one I'm talking about is you talk about our sense of direction. I loved that chapter so much. This blew my mind. You talk about how they did a study where they would take people, I think they would, like, drive them all over, they wouldn't know where they were, basically. And then most people could still, even having been all around and turned around, they could still basically point in the direction of home unless they used a sort of Faraday cage-type situation where they were blocking them off from the electromagnetic--

Jackie Higgins: Magnetic information.

Melanie Avalon: Yeah, and then they couldn't anymore, which is fascinating. The second part would be the tribe that always knows direction, the tribe that always knows have they studied them with the Faraday?

Jackie Higgins: So, Joe Kirschvink, who's the chap at MIT who I spoke to, whose most recent study that suggests we do have a sense of direction, is hoping to get out and study them properly and analytically. But they do have an unerring sense of direction, whether it's informed by stars in the sky or where the sun is in the sky, or how long the shadows are or whether it's informed by visual cues that they're picking up on, or whether it's informed by another sense is the question.

So, of all the senses-- I have 12 chapters in my book. The sense of direction is not yet proven in humans, but there're lots of tempting information to suggest it could be there. It's certainly proven in lots of species. Migratory birds are the example that I use. But even within animals, what's been difficult and what scientists have been trying to figure out is they've been looking for the sense organ that enables them to detect the magnetic signals.

So, the question is whether there are two leading theories at the moment. One is that there are little magnetite crystals inside cells that essentially act like a mini magnet, like a little mini compass. And the other really fascinating work, again, very contemporary, coming out of all sorts of universities around the world, is a theory of the quantum compass and this idea that, say in a bird's eye there are these proteins called cryptochromes and they have some form of quantum reaction with the magnetic lines that enables the bird to perceive the magnetic fields. And they're theorizing that these birds could actually see the magnetic field.

So, in addition, my first two chapters are on sight. I talk about cones being the sense that give us color, and rods being the senses that enable us to see in the dark. So, in addition to the cones and rods of the bird's retina giving this bird the ability to see the ocean that it's been flying over for the past few days, day in day out without stopping. In addition to that, there may be some overlay whereby they can see which way is north and which way is south. Obviously, they don't think of it as north and south, but to be able to give them information on how to give them a sense of direction.

Melanie Avalon: Yeah, that is crazy. And that makes you think, like, if you could have that experience of whatever they see, because I think, like hearing this now, we're like, oh, well, if they saw that's not reality, it's just a direction that they're interpreting. But if that's what you see, then to them, maybe that literally is real-- like that is the world.

Jackie Higgins: That is reality. Well, one of my favorite bits at the very end of the book, the tale of the duck-billed platypus and I pose this idea that this creature senses electric currents. And this is something we can't do unless they're so sharp that they give us a pain reaction. So, we do not have this sense. So, its reality is different to us. So, it depends on the senses that animals have that construct your reality. And within our world that we see, we smell, we engage with our five senses plus with our regular toolbox of senses, within that there are many other realities.

Realities that perhaps birds that see different many more colors, or different colors, or UV, or polar butterflies that see polarized light. So, this is wonderful, I go back to this Baron Jakob von Uexküll, who was a biologist who proposed this idea called the umwelt, which is this wonderful word, I think, for basically your umwelt is your reality. It's what your senses have constructed for you as reality.

But the duck-billed platypus is a umwelt. It's radically different from ours because it's able to sense a whole new dimension of what's really out there that we can't. So, it's umwelt is different. So, all these creatures, the world is full of very many animals with very many different solutions to sensing the world and very many different umwelts. So that should question our reality. Our reality is just one reality of very many. So, the world is a much more interesting and intriguing place, tasted through a goliath catfish's skin or felt through a star-nosed mole, starry-nosed or whatever it is, through an octopus' sense of body.

Melanie Avalon: I'm glad you brought up umwelt. It's funny because I had that in my notes as well and I didn't remember it from the book and I was like, is that a typo? I don't know what that word is.

Jackie Higgins: It's such a great word, we should use it.

Melanie Avalon: It's amazing. I know. We need to integrate it into our common vernacular because it describes something so well.

Jackie Higgins: A couple of weeks ago, I went to a WWF, a World Wildlife Foundation, evening where Alastair Fothergill, who's a series producer of this new series that's hitting the BBC. It started this weekend with David Attenborough basically doing The Blue Planet, but just on British Isles. I was up on the podium next to Alaistair and a few other people, but we're watching clips from this latest Attenborough series. And, of course, making programs, making documentaries it's a feast of visual imagery. And there were these wonderful scenes of turns, I think it was turns on a beach in Norfolk.

And of course, what we were seeing, I knew was completely different from what-- that's right it was a peregrine falcon catching one of these birds. And what that falcon sees is completely different from how we would see reality because it's got this-- no bird is able to see with such detail at such distance. It's almost like, "If a bird is caught in its eyes, it's almost like it's been caught in the hairlines of a rifle." So, we were talking about what we see in these wildlife films, the visual feast of them.

But there's so many other senses that are playing out in reality in those scenes that are shot. I mean, if only we could make movies. It's always visual but including the smell and the touch and the taste and sounds. Quite often a lot of these sounds are created afterwards in wildlife as I know from doing it myself. You go to Foley Booze and you kind of munch your cucumber, and you lay that sound on the caterpillar as it's munching through the leaf. Or you take a damp cloth and you flip it and it creates a kind of [onomatopoeia] lovely sound of a bird flap, a wing flapping. Anyway, yes, I've gone off one.

Melanie Avalon: No, no, no. I love it so much. I've been haunted for years about the concept of "I just don't know if the colors I see are the same colors that you see." Like, "What if all of my reds are your greens?" And what if it just translated that way?

Jackie Higgins: I'm speaking to scientists. Highly likely there's a variety in the way we see color, highly likely. Maybe our photosensors are tuned just a tiny bit differently. But then also how the brain computes, creates a million different colors from our three different types of photosensors. It's very likely that what you see as red is slightly different from what I see. And we know that from people who have serious issues with confusing red and green or being, as my first chapter talks about people who can't see color at all. They see the world in black and white. So, yes, color is not something that is out there in the world. It's totally a creation of your senses and your brain. Color is an easy one to envision, but then when you get into the other senses, it's even more of a mind bend.

Melanie Avalon: Something-- I swear these are things I've been thinking about for years, since childhood. I was so happy. I used to always think about like literally when I was really little. I think when I first learned about how color works or light and color and how it's reflected, I started thinking about, does that mean that in a dark room, like a red apple, it's literally not red? It's not that I just can't see the red. Like, it's literally not red.

Jackie Higgins: It's only red through your eye and my eye and then through another animal that can't see red. And then you've got this coevolutionary, conversation between-- remember that the apple evolved and evolved those pigments in order to attract particular eyes. And I'm not talking about Eve and the apple, but I mean, whomever the apple first, you've got this wonderful coevolutionary race between flowers and insect pollinators or fruits and birds that disperse them.

So, actually probably what's important is how the fruit or the flower looks to the creature for whom it's enticing. Bumblebees, all those wonderful stories of bumblebees being able to see UV light. And then you have blooms, flowers that have these little runway patterns of UV tracks saying "This is the way to the nectaries, follow these lines and we'll guide you in."

But of course, these signals are completely invisible to our eyes. So this is back to the umwelt and then shared umwelt, I mean, shared ecologies and communities within the broader picture of this extraordinary world that is more diverse and led than we can imagine.

Melanie Avalon: Something I thought was really mind-blowing is you talk about the role of randomness in seeing. It's something about how single photons are bouncing around and there's an aspect of randomness as to whether or not they actually land on was it the cones or the rods.

Jackie Higgins: On a sensor, the rods. This is the story of the deep-sea spook fish that lives in the ocean abyss where so few photons reach down from the sun. The sun's got to hit the water and then that light's got to travel down and down and down and it loses energy as it goes, and then very few photons reach the depths where this fish is, and then they might hit the eye, but they might bounce off at the wrong angle or they might hit the retina, but not the protein that's going to react to within the rod to redoxin, which is going to react and send a message ultimately to the brain. So, yes, I hadn't thought of that. I wrote it but I wasn't thinking of the random aspect. But of course, of course.

Melanie Avalon: Because I read that and I was like, "Well, that's a little bit distressing because that means everything I see-- if there's an aspect of randomness to it, then maybe I could be seeing things different ways." But I was wondering-- do you think the brain-- because I was actually reading an article last night, it was not about this, it was actually a list of like 10 random unique types of pie. Don't ask why, but in any case, the first one on the list was an apple pie not made with apple. And they were talking about how people eat it and still will say it tastes like apple pie. They were talking about the role of the perception of the brain and how it fills in information, if it's like expecting something. So, I was just wondering if maybe with seeing, even if there is an aspect of randomness, maybe my brain has sort of decided what everything looks like. I'm just conjecturing and it just like goes with that.

Jackie Higgins: You've got this bottom-up influx of information from the senses to the brain, but then the brain has this top down. It chooses what it listens to and what it doesn't listen to. I remember when I was at the BBC, we made a series on the brain. For me, the most extraordinary sequence was these experiments that had been done, I think it was with basketball. They basically filmed. They'd ask someone who's sitting in a booth watching a clip of people playing basketball.

Melanie Avalon: Oh, I love this one, I love this, I love this one.

Jackie Higgins: Yeah. The person asked, "Count the number of basketballs. Watch that ball and see how many." And your brain, therefore top down, is so focused on counting that it doesn't know not the elephant in the room, but the gorilla in the room. And then they say, "Okay, we're going to play back the same clip and this time look for the gorilla. And you see there was a gorilla the whole time, except you never saw it." So that's a classic example of your brain is very much what attention it chooses. Your brain also is in charge of what you're seeing. It's not necessarily the reality.

Melanie Avalon: You really do only see what you want to see in a way. Maybe I guess maybe the first time you see something do you see it more objectively and then you make assumptions?

Jackie Higgins: I mean, these are deeply philosophical questions. I mean, that's, I think, why this subject area really interests me because it does leave science and you are left with a lot of metaphysical questions. The questions that are quite difficult to prove one way or another. But the delight of asking them is great.

Melanie Avalon: You talk about how we historically thought that the cortexes of the brain, like, there's like the part of the brain that sees that it's all individual. Maybe it's more nuanced and more complicated than that. So, how does it work in the brain?

Jackie Higgins: Yes, I suppose, again, the story of Eşref Armağan, who is a blind artist and his brain has been-- so he feels the world and then he draws what he feels. And of course, he's been told various things, like he uses color in a naive way. He's been told when it's an apple to paint it green or to paint it red. He's never seen color, but he feels-- I mean, for him, the world comes alive under his fingertips and he says, he went talking to him, he's a lovely gentleman, and he says how feeling the world with sense of touch has eradicated his blindness. He was studied at MIT by neuroscientists who asked him to feel objects and then draw them. And while he was doing that, they scanned his brain.

And what was extraordinary is that and I suppose it's not extraordinary when you think about it, the part of our brain, our somatosensory cortex is the proper name, but it's the part of our brain that basically deals with the information that our fingers are feeling about the world. How our sense of touch and our body is feeling about the world. Basically, our sense of touch is processed in this area of the brain. And of course, with Eşref, it's not like that part of the brain is not being used. It's not like it's lying fallow doing nothing.

Of course, it's being co-opted by the sense that most needs processing. And for him, that is his sense of touch. There's a brilliant book by Eagleman called Livewired. It's called Livewired over in the UK. I don't know what the title is, but it came out around the same time as Sentient. But he's a neuroscientist who talks about the plasticity of the brain and the fact that the brain is live-wired. And in my book, because of the book, I talked to a scientist called Alvaro Pascual-Leone, who did these amazing studies where he asked people would they mind foregoing their sight for a while.

And so, he blindfolded them and they put little bits of photographic paper underneath the blindfold. So, they knew that these people had never cheated, because if they cheat and let in a crack of light, that little piece of photographic paper would be exposed. So, they knew that these people hadn't cheated for a few days. Basically, these people were blind or his colleagues taught them how to use braille to read. So, they were exercising, they were using their sense of touch. And in that short period of days, their brain started, its live-wired, it started to rewire.

And so, parts of the brain that they normally had used for vision were now being co-opted by their sense of touch. So, our brain is this plastic organ within our skull that is basically processing whatever information it can get hold of. And so, Alvaro Pascual-Leone was talking about the fact this is a completely different way to view the brain, that it's not divided into these-- the cortex is not divided into this is the area for sight, this is the area for hearing, this is the area for touch. That's an old-fashioned view. And looking at these unusual brains has taught us so much more.

Melanie Avalon: With all of the different senses, because I know you talk about it with at least one of them, which I think was smelling that, like, if we tried to smell better, we could-- so for all the different senses, if we really focused, can we enhance any of our senses basically?

Jackie Higgins: Yes. So, if we try to smell better, I think what I mean is and as you said, focus, if we give it attention, did I read you're interested in wine?

Melanie Avalon: I am, yes.

Jackie Higgins: Yeah. So, there you go. I bet you give every glass of wine that you sip and then drink and enjoy a lot of attention. You probably smell it and taste it in a way that many people won't. And because you're exercising that sense, you will improve that sense. More of your brain will be devoted to understanding how that wine smells, why it smells different from the one you had the night before. What's different about it? So, absolutely. And that is one of the messages throughout the book, the fact that our brain is plastic.

There's the lovely story from Oliver Sacks of the gentleman who hadn't lost his sense of balance, but he was walking at a tilt and so his friends had called him the Leaning Tower of Pisa. And this gentleman came into Oliver Sacks' office and said, "Well, I'm not quite sure why I'm here. There's nothing wrong with me." As he was leaning over at a tilt, he refused to see it. And I think that Sacks had to film him and then play it back for the gentleman to realize that he wasn't straight.

He built some spectacles which basically, I think, had a little plumb line dangling off the bridge of the nose as far as I can gather from the way that Sacks wrote about it. When he saw this plumb line and he saw it was swinging to one side, he would then adjust his stature so he would be straight. It probably felt quite awkward to him to begin with, but he kept doing that and the brain consequently adjusted and he didn't need to wear the specs for him to walk straight again. Yes, absolutely. The plasticity of the brain means we can improve upon our senses by giving them attention and just exercising them. Like we might practice a football school-- football kick or whatever it is.

Melanie Avalon: And it can also happen without us realizing it. Like, you talk about the role of balance again and dancers and dizziness that blew my mind. You talk about how I don't know what it's even called.

Jackie Higgins: Mad pirouettes, the ballet dancers.

Melanie Avalon: Mm-hmm. Yes. And how they don't get as dizzy. But there's actually something really happening in their brain with that.

Jackie Higgins: Yes. Again, amazing study conducted in London by a local scientist and he wanted to understand the ballerina's brain. What is it about the ballerina's brain that means they don't get dizzy? Ballerinas are taught all sorts of techniques. They snap their head around. So, your balance organs are in the inner ear, locked inside your skull. They work on fluid and hair. And so, when you're turning around, if you lock your eyes back onto a fixed point, that should minimize the amount of information and it should quieten down your balance organs. They'll fire less to the brain. So, that's one technique.

Seemungal looked at the ballerina's brain and realized there was a difference between their brains. And I think from memory, he juxtaposed them against people who were equally athletic, but not for balance. I think they were rowers or something like that. So, these people were very fit, but they had very different brains. And I think it was part of the cerebellum that is used for balance had shrunk. So actually, they were getting less information from the balance information because I suppose it's because their sense of proprioception has stepped in. So, they have this immaculate sense of balance by knowing where their body is. So, they don't maybe need to listen to their balance so much anymore. They're not going to fall over because they have such a highly trained body. Their sense of balance was reduced.

Melanie Avalon: Reduced. Wow.

Jackie Higgins: Which was completely counterintuitive.

Melanie Avalon: So, dizziness, are there different causes for it or is it always a saturation of too much movement and so too much like balance stimuli?

Jackie Higgins: No, I think with all the unusual cases that I encounter in the book, there are always multiple stages where the information doesn't get through. So, it could be at the level of the sensor or it could be, for example, let me think with regard to that.

Melanie Avalon: What happens with alcohol?

Jackie Higgins: Yeah. Oh, with balance. So, I doubt that will addle the sensor. I would think that will addle the brain. The colorblind people on the island of Pingelap who I discussed, they had a mutation that meant that the cone wasn't working. So, that's where the sensor is working. And then you could talk about someone like Ian Waterman, who's unable to feel his body, who's lost his sense of proprioception, his sensor, the little proprioceptors were working, but basically the motorway, the nervous highway up to the brain was wiped out. So, there was no communication from the sensor to the brain.

And then in the brain, the chap whose balance isn't completely right, I think he had Parkinson's. The chap who I was just explaining earlier, The Leaning Tower of Pisa from Sacks' wonderful book. He had Parkinson's, so I think aspects of his brain weren't quite working. So, essentially it can go wrong. Dizziness simile can go wrong at each and every stage.

Melanie Avalon: Yeah. This is so fascinating. Another sense I would love to talk a little bit about is one that I think people think about sometimes with culture and romance. So, pheromones, are those real? Are we actually attracted to people through these scents?

Jackie Higgins: So, pheromones are certainly real. Whether the love potion for humans, the love pheromone that we can't resist is real is not yet proven. There're some really interesting studies happening at the moment on babies. I think Benoist Schaal, university in France, and I don't know whether the work is yet published, but I know he's looking at pheromones that are detected in mother's milk, that enable babies to guide them towards the breast and help them with breastfeeding.

So, that possibly will be the first human pheromone to be a love drug between mother and child of another kind. But there are definitely pheromones in the animal kingdom. And I talk about the very first pheromone to be discovered, which was bombykol, which comes from the silk moth. But there are also lots of interesting and that's what the chapter looks at, lots of interesting ways in which smell subconsciously subliminally plays to perhaps our sense of love or attraction.

Really interesting study on the MHC genes. You mentioned in passing the major histocompatibility complex genes, which essentially are genes that look after our immune system. And there's been some really fun studies on getting members of the opposite sex to smell sweaty T-shirts and they make choices on which smells they prefer based and when the numbers are crunched what they find is a woman might choose a man who has compatible genes with her MHC complex.

The idea being that by having babies together you'd create babies with stronger immune systems. So, there are many ways in which smell does get involved in dating, in attraction, but we have yet to find the human love drug, Puck's love drug for Titania. But there are scientists who think it will be found-- It's been found pheromones, I mean, since that discovery of bombykol in moths, pheromones have been found nearly everywhere throughout the animal kingdom in so many different places, I think most recently in elephants.

So, this is another theme of the book, the idea that we think we're special, that we're different is to me as a zoologist, a bit of nonsense. We have a deep evolutionary past with all these creatures. We share commonalities in many different ways. So, I'm of the belief that we will find a human pheromone whether it's as compelling as people fear, whether it completely banishes free will, I doubt, but I think I suspect that we will find one and it will encourage attraction. It's all in the gray areas rather than the black and white.

Melanie Avalon: I find it interesting that I guess I don't really know enough to make this statement but it seems like there are a lot of studies on it, so I find it interesting that it's not more crystallized yet in the research.

Jackie Higgins: Yes, well, it's highly political as well so the evidence when it comes is going to have to be watertight.

Melanie Avalon: Okay, that makes sense.

Jackie Higgins: If and when it comes.

Melanie Avalon: Because I was thinking about it, because you mentioned how in the studies, it does seem to indicate, like with the genes, that opposites likely attract. And so, then I was thinking, well, that's interesting. So maybe evolution set us up for mating and procreation in the beginning, but maybe it didn't set us up so much for longevity in relationships, because I've heard the opposites attract, but similarities stay together is what they say. So, I just wonder if it's hard to find the perfect partner who's your opposite pheromone-wise but similar as far as personality and getting along and all of that.

Jackie Higgins: I think, I mean, the thing is we use our brains and we're not dictated by our senses and things. And there are very many other things that come into play when we're thinking about attraction nowadays. So, I think it's more complicated than just smell. I think smell is part of the story and is part of the story in a way that is surprising and intriguing but there are very many other important factors and looks, I mean, the way someone looks, so, yes, it's complicated. We are complicated. I don't think we are other, but we are in comparison to other species there are very many commonalities, but we're complicated in different ways.

Melanie Avalon: Just a few last things. Speaking of genes and longevity, because I'm really interested in all of that. I was fascinated. You talked about owls and their sense of hearing and how their hearing doesn't seem to age.

Jackie Higgins: Yes, that's wonderful. Yeah, that's a wonderful story. I wasn't expecting that when I was looking at the great grey owl and our sense of hearing. But that's an example of where contemporary science pops up in the book. There are remarkable similarities between the way that we hear and the way that owls hear and in the senses that we have to hear and in the senses that owls have to hear. So much so that scientists are looking to owls to cure human deafness because the extraordinary thing about the owls that they've studied and there's this lovely study coming out of Germany with owls, where they've studied the hearing abilities of these owls from when they were little fledglings all the way to the ripe old age of 20 odd, a grandmother, a queen of the colony of the owl. And her hearing is just as good as when she was six months old or whatever it was. So, yes, owl's ears do not age. They are just as good as hearing as they are when they're fledglings. So, that's a lovely story. Yeah, and I was surprised by that. Again and again it's back to the message of the book, which is the similarities between us and these other creatures that-- I mean, imagine if the owl creates us, for us a cure for deafness.

Melanie Avalon: No, that's amazing. Well, I want to be really respectful of your time. So maybe just one last question about time. You have a really amazing chapter. We touched on it briefly earlier but with the spiders and circadian rhythms. And you talk about isolation studies and what happens when people go in basically where they're not exposed to a concept of time or light and how do they adapt, you know, accordingly to that. Okay, so I have heard and you mentioned this in the book, you talk about that the Earth's rotation is, 24 hours-ish, I don't know if it's exactly 24 hours.

Jackie Higgins: Yes, and it's changed over-- yes, it's changed over time.

Melanie Avalon: Yeah. I didn't know that. I was like, "Oh, that's interesting." You mentioned in the book that when they do these studies that it seems that most people's inherent circadian rhythm is actually a little bit longer than 24 hours. I had heard that a reason that people were like night people versus early people might be that they have shorter or longer circadian rhythms. Do you know if there's credence to that?

Jackie Higgins: Yes. Really interesting work done on larks and owls. And there is definitely, they call them chronotypes. So, whether you are a person who gets up in the morning or a person who likes to stay up at night. And the science is very established on this. There's a wonderful book, actually, Internal Time by Till Roenneberg, which explores these different chronotypes and how they are and they're beginning to work out the genetics of it. And they've discovered genes that make someone a lark.

Again, looking at unusual people who can't-- who fall asleep at night and get up really early. They do have different genes. And there is a sense that this chronotypes are genetically coded within us. They also change throughout our life. So it's obviously altered by hormones, but teenagers definitely tend to be more owl-like. And then as we get older, we tend to become more lark-like.

But apparently, women tend to be more lark-like than men. So, there are these interesting broad generalizations. Yes. So, that's a fascinating study. I mean, the sense of time, I talk about it in terms of circadian time, but of course, time is very many things. I was reading the other day, it's the most used noun in the English language and it means very many different things. So, we could talk about the perception of time, how time unfolds into seconds and the minutes.

And these circadian clocks are something different. Our body clocks are our 24-hour clocks that keep us on track with night and day. They enable our bodies to basically function on a 24-hour schedule. So, we know when to sleep, we know when to wake up, we know when to get hungry. We're very different biological creatures in the morning to at night. And there're all sorts of amazing studies about. We proofread better at certain times of day, we swim better at certain times of day. I mean, there're all sorts of extraordinary studies. So yes, yeah.

Melanie Avalon: A really quick question because you mentioned men versus women and you also talk throughout the book about how some things are different in men versus women, or like with pain, for example, that women have a higher tolerance for pain. Have they studied this in animals for all the different senses, female versus male?

Jackie Higgins: I don't know, actually, I don't know. And with the pain issue, it's difficult to know. So just coming back to that, because there's no way of measuring pain other than asking someone to say, "Okay, on a scale of one to ten, where would that lie? So, the evidence from women is because a lot of women have gone through childbirth, they've probably experienced something more painful than most men. So, when they're told, okay, on a scale of one to ten, where do you fall and you've got a bit of toothache and it's nothing like the labor you enjoyed last week, you go, well, it's a two, but someone who hasn't. So, it's incredibly subjective.

So, I can't say that women have a higher pain tolerance than men. That's a tricky sub-- I do talk about how they're possibly better at touching than men because we've got smaller fingers and we have roughly the same number of touch sensors on our tips of our fingers. And given they're squeezed into a smaller area, we're probably a little bit like the star-nosed mole us women, in that we can feel the nuance of ridges and topography closer, more detail with more acuity than men. The pain thing, golly, I don't want lots of men to write and complain. [laughs]

Melanie Avalon: Okay, so clarification for listeners.

Jackie Higgins: Perish the thought. [laughs]

Melanie Avalon: Maybe someday there'll be a study showing men have a better sense of direction.

Jackie Higgins: Yes. Or maybe not. [laughs] I'll contest that too. [laughs]

Melanie Avalon: Well, this has been absolutely so amazing. Thank you so much, Jackie, for your work. I just find it so fascinating, and I learned so much. I'm really excited about you coming out with another book.

Jackie Higgins: Aww. Thank you. Melanie, you've done a real close read of it and digested it, and I really appreciate that. And you've brought out some lovely things to talk about? So, thank you.

Melanie Avalon: The last question that I ask every single guest on this show and it's just because I realize more and more each day how important mindset is. So, what is something that you're grateful for?

Jackie Higgins: Oh, so many things, but maybe for my senses. And I think that each chapter I wrote made me incredibly mindful of whatever it is I was writing about. So, from the first chapter, where I talk about color, I became really fascinated by, I don't know, looking all the different greens that I could see in a blade of grass or the chapter on smell, I became really interested in smelling my morning coffee. I've mentioned him before, but Oliver Sacks is a big influence and he does have a lovely quote in his book about gratitude. And I use it at the top of the book. And he talks about when he's just discovered that he has terminal cancer. He writes his last op-ed for the New York Times, and he talks about the gratitude he feels in just being a sentient animal on this planet. I'm so behind that. I think those are words we should write large somewhere and think about every day.

Melanie Avalon: I love that so much. Well, thank you so much. And I can't let you go without asking you what is your favorite animal. I'm sure you get asked that all the time. I have to know, though. I have to know.

Jackie Higgins: My cat would say-- it will get very cross if I don't say a cat. My whippet would get very cross if I choose that-- we have a Vizsla as well. I don't know where I am. Each day for me is a new favorite. I think I know so much about different animals that each day is a new favorite. I do have a soft spot having written sentient for the octopus.

Melanie Avalon: Yes, listeners, if for nothing else. I mean, get the book. There's so much more that we didn't even talk about. But the chapter on the octopuses, which I learned is octopuses, not octopi, will blow your mind. What happens when you cut off there?

Jackie Higgins: Literally. It really will.

Melanie Avalon: So that's such a teaser. Get the book. So, thank you so much, Jackie.

Jackie Higgins: Pleasure. It was really lovely chatting to you. And I look forward to another time when I have something more to talk about. [laughs]

Melanie Avalon: That would be incredible. And how can listeners best follow your work?

Jackie Higgins: So, I'm in the process of-- so I'm on Twitter. So, you can find me on Twitter. I'm on Instagram. Yeah. And I'll be online soon as well. I've realized these are things that as an author I need to do. So, those would be the best bits. But Twitter is something I use the most, perhaps.

Melanie Avalon: Awesome. Well, we will put links to all that in the show notes. Thank you so much again. I really hope we can speak again in the future because I just love everything you're doing and I'm so grateful for it. So, thank you for your time.

Jackie Higgins: Thank you. It was my absolute pleasure. Thank you. It was really fun. I enjoyed our chat.

Melanie Avalon: Have a good night, because I know it's later there. Bye.

Jackie Higgins: Good night. Bye.

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