Athena: 00:04 Have you been zombified by morbid curiosity? Welcome to the Zombified podcast, your source for fresh brains. Zombified is a production of Arizona State University and the Zombie Apocalypse Medicine Alliance. I'm your host, Athena Aktipis, psychology professor at ASU and chair of the Zombie Apocalypse Medicine Alliance. Dave: 00:28 And I am your cohost, Dave Lundberg-Kendrick, media outreach program manager for ASU and brain enthusiasts. Athena: 00:35 You love brains. We love brains. So yeah, it's kind of our thing. [Dave agrees and laughs] Dave: 00:41 And today it's morbid curiosity, Athena: 00:45 Morbid curiosity, yeah. So we're going to hear from Barb Natterson-Horowitz. She is a professor both at UCLA and a visiting professor at Harvard. She's also a doctor. She has worked on, sort of, topics that range from very mainstream kind of evolution in medicine and how we can use evolution to understand ourselves, to topics like what she's writing her current book on, uh, which is adolescence and looking at adolescence from an evolutionary perspective. So how can we actually understand what human adolescence is like better by taking a really cross species approach. Dave: 01:34 So now, is that what you guys talk about today? Athena: 01:37 We talk about that and we get to the topic of morbid curiosity, because that seems to kind of be an adolescent thing. Dave: 01:45 So, so tell me what you mean by morbid curiosity. Athena: 01:49 So the kind of curiosity that will get, can get you in trouble, like can you know, make you die, for example. Like, say you are in a situation with a dangerous predator or maybe there's a zombie on the horizon and you just want to go towards it. Dave: 02:05 Okay. Just to see what it's up to? Athena: 02:07 Yeah. So why would you ever do that from an evolutionary perspective? Dave: 02:12 Do you want me to answer? I have a guess. [laughter] Athena: 02:13 Yeah, give it a try! Dave: 02:15 I mean, I guess it would give you useful information, right? Athena: 02:18 Yeah, that's kind of the direction that we go. So let's hear from Barb Natterson about morbid curiosity. Dave: 02:25 All right! Sounds good. Intro Music: 02:27 [Intro music] Barb: 03:04 So I'm Barb Natterson-Horowitz and I am an evolutionary biologist and a physician, a cardiologist. And in my work, I turn to the natural world for insights into human health. Um, specifically I like to look comparatively across the world of animals for commonalities and differences that can illuminate and sort of inspire how physicians and people in the health field approach medical problems and psychiatric problems, but also to sort of look broadly for insights from the world of animals for development and for every aspect of human life. Athena: 03:49 So, what can we learn from nonhuman animals that can inform how we understand ourselves and also how we take care of ourselves and manage diseases and promote health. Barb: 04:03 Yeah. And that's exactly, that's sort of how this all started. I mean, I should say that um... So we're having our meeting here today in my office in Cambridge. Athena: 04:10 Yeah, your awesome office! This is beautiful. Barb: 04:11 Well, you know what these are?These are... so everybody knows that John James Audubon did birds. [Athena agrees] But he also had the mammalian series, the mammals of North America. So these are - almost all of those are birds - but these are almost all... and this is my favorite one behind you. And these are all part of the, um, the public domain now, so you can get these from the national site. I mean the, and so anyways, so I just- yes, these are all John James Audubon prints. But yeah, so we're in Cambridge right now because I'm a visiting professor in the Department of Human Evolutionary Biology. Uh, and now, but I am also a professor of Medicine and Cardiology at UCLA. Athena: 04:58 And you do that because you've cloned yourself, so you can be in both places at once. Barb: 05:02 [laughs] Yes, I have made a secret discovery, exactly. [Both laugh] Which is not a secret anymore, but yeah. So the point is that, um, initially when, I mean I spent 20 plus years as a physician, as a cardiologist, you know, as an attending physician in the cardiac care unit at UCLA, teaching medical students and interns and residents and cardiology fellows, um, treating high blood pressure and heart attacks and all of that. Um, and then I had this experience that really gave me a closeup view of the world of veterinary medicine, which really transformed my perspectives. Athena: 05:37 What was that experience? Barb: 05:38 Oh, well, I was basically, at the time I was, I was the director of cardiac imaging for our Arrhythmia group at UCLA, arrhythmias are electrical disturbances of the heart, like atrial fibrillation. And I was doing tons of cardiac imaging around that issue and I got a call from one of the veterinarians of the LA Zoo that one of their chimpanzees had had what they thought was a neurological event and they wanted me to come to the zoo and to do a cardiac ultrasound on the animal to see whether there had been, you know, there was a blood clot that could have caused a stroke, etc. So I started going to the zoo, basically. Athena: 06:16 When was the last time you'd been to the zoo before they called you? Barb: 06:19 Oh my God. That's actually a really, really good question. Um, wow. Well, well, here's kind of a fun fact. The uh, patient that they called me about was a female chimp whose name was Pandora and what's really beautiful about Pandora- and Pandora ended up doing really well and lived a number of years. She was very geriatric when she eventually passed recently. But, um, I ended up, I really got connected to her because I took care of her and it was my first experience going to the zoo as a physician, so she had a lot of meaning in my life. And as I was reading about her, I learned that she had been brought to, she came to the LA Zoo, I believe it was like 1965 or 66, in fact there is a picture of her as an infant in the arms of the veterinarians then. [Athena expresses awe] And my parents, I grew up in LA, you know, I went to like public schools in LA and I was like an LA girl and my folks loved the zoo and they loved Griffith Park. So we used to go to the zoo a lot and we would hike in Griffith Park and they would go to the zoo. So I have this feeling like I've known Pandora. [Athena aww's] I can't prove it, I don't really remember but- So yeah, but it was a, it was a cool experience. And that then led to... they asked me back to image their gorillas and their other primate patients. And then eventually I started doing more imaging under the supervision of these amazing veterinarians who are board certified. But for me as a physician, I had this 'Aha!' moment that, you know, even though I was a full professor of medicine and I felt I knew a tremendous amount about a wide range of cardiovascular diseases, I had not thought at all about which of those diseases could also naturally or spontaneously occur in nonhuman animals. It just wasn't part of my thinking. And so what happened through this experience of being in the world of veterinary medicine is I began seeing that, whether it was neurological, a stroke, or whether it was heart failure, whether it was breast cancer or whether it was, um, leukemia or lymphoma or a brain tumor, or even eating problems or anxiety kinds of problems, that this vulnerability to get sick is species wide. And that human exceptionalism had been a kind of blindfold that I had and that by taking it off, I was just able to see this whole new world. And so my career shifted from taking care of human patients all the time to begin looking for connections between animal and human health, which led me to the question of common ancestry and ultimately evolutionary biology. Athena: 09:11 And so it was like this revelation that all of life and especially mammals have a lot of similarities to us in terms of susceptibility to disease and what makes them vulnerable to disease. Barb: 09:26 Absolutely. But what happened as part of my journey, it was a journey of humility and awakening, was- I quickly learned- So I started, I was still working full time as a cardiologist at UCLA doing a lot of teaching and a lot of clinical work, but I was going to the zoo as much as I could when I was asked. I was going to veterinary conferences, I was visiting with vets, I was reading the veterinary literature. And, um, quickly I started hearing about, first on rounds at the zoo, actually about some animals who had self injury and were being treated with selective serotonin reuptake inhibitor drugs, right? Drugs like PROZAC and Zoloft. And I mean, to me self injury, um, I associated it with like with the cutting behavior that you might see in an adolescent or um, this kind of thing. [Athena agrees] So it was really interesting to even hear the, in that context, the use of those kinds of psychotropic drugs and then learning about anxiety, particularly separation anxiety in domestic dogs and learning about sexual dysfunction in stallions and then learning about eating disorders in a whole range of animals. Um, and as the sort of, the evidence mounted in front of me, I realized that not only was my- again, my human exceptionalism had been a blindfold, so, A. B, that the vulnerability to these problems is pretty broad. And, finally, that in order to- that this insight, that these were taxa-wide, immediately forced me to consider alternative explanations for- causal explanations, in other words- it led to new hypotheses that were not even possible in my mind without this comparative information. Because if it's just a human thing, then we're just going to look for exclusively human explanations. So it really is it, I mean, you can vomit because this is such a trite, but it was, it was paradigm- it was, I mean, it shifted... [Athena agrees] It blew my mind. Athena: 11:59 Blew your mind, your brain, whatever you want to say. [Both laugh] Well I want to talk about morbid curiosity with you and as I was thinking, and you're talking about your interest in the big killers and all that and like- 'wow, Barb actually is literally, she has morbid curiosity!' You're curious about all these morbid things. Barb: 12:22 I love that. I love it. Athena: 12:24 So you're like the personification of this very episode on that. [both laugh] Barb: 12:28 Yeah, no, so I love this kind of zombification idea. So I mean it works in so many ways! [both laugh] Athena: 12:38 Yeah, so the whole morbid curiosity thing of like, you know, why is it that we are even interested in things that have to do with, you know, potentially dying or getting injured or threats, monsters... [Barb agrees] Barb: 12:53 So my new project, what I've- all the medical stuff was just sort of set up, that, although I'm still interested in that, I sort of moved to using the same methodology that I developed for studying this perspective on human disease and animal disease and to look at development and particularly, I set my sights on understanding one of the most challenging, misunderstood, confusing, and terrifying phases of life, which is the period between sort of childhood and adulthood, which sometimes is called adolescence, and so this has been what I've been doing for the last five years. And I've been, I've just finished- well, the new book, which is based on this, is going to be published in September. [Athena congratulates Barb] Well, here, I'll set up the name. So, what do you call the period of life between childhood and adulthood across all species. Wilhood [Athena laughs] So anyway, so one of the, so what I needed to do, I needed to find a way to use, to turn to the natural world, to turn to the world of animals, to see whether there were ways to better understand these really scary and tough aspects of adolescent life. Athena: 14:17 Right, because adolescents are like, they take a lot of risks, they often do things that seem like they're really not in their best interest and so how do you explain all that? [Barb agrees] Barb: 14:26 They seem zombified by this developmental phase, right? So, so the first thing that I needed to do, it was interesting because in the beginning, and Catherine Bowers who we are, we've been research and writing partners and all this, we needed to figure out, um, what animal adolescence actually was and what that meant. Athena: 14:48 Yeah. So what, I mean is there such a thing as animal adolescence, like can we say that for sure? Barb: 14:54 Well, I feel I can say for sure that there is at this point and um, you know, human adolescence is typically defined, has been defined by- the onset of puberty is the beginning, and then it sort of, it ends and different organizations have it ending at different times. So, um, in some circles it ends at 21 in other, other groups feel that it ends at 23... Athena: 15:22 So is it just like an arbitrary number or is it based on something developmental that is supposed to be happening in the brain or the body? Barb: 15:30 Yeah, the, well the question, I mean baked into the question is the problem because the definitions vary depending on the criteria. So, this increasing awareness about the unique neurological development of the adolescent brain has led to, sort of awareness that the, that the brain continues to develop through certainly the late teens, early twenties, late twenties, and in some, some instances even thirties. So there's been this sort of expansion of it if you're using the criteria of brain development. Right? But then there is also, um, there are other criteria. There are legal, there's a legal definition right, there is- so the American Academy of Pediatrics has a different- the American Academy of Pediatrics, the CDC, the WHO, I mean you have groups that are really, you know, evidence based and, but they, they differ. So it's, it varies. Athena: 16:30 So then how do you apply that to animals to say, like, we can tell that there is an adolescent period in nonhuman animals. Barb: 16:39 So, so the way that we did that was to first look at puberty across a wide range of animals and, you know, if you're going to, if you're a sexual animal and you're born as a juvenile, you're going to have a period where there's a transition and you're going to become- you're going to go through puberty. I mean, sharks go through puberty, right? And, um, whales go through puberty and, we, you know, it's even ancient animals, right? Every Neanderthal, well, I mean, every, you know, Australopithecus right? Like Lucy and... Athena: 17:15 Yeah, so there's like, there's like puberty and there's some time until you're fully mature. Barb: 17:20 Right, and what that, and what we realized is that adolescence, a lot of the way adolescence is even defined sort of was very much entrained to the physical, to the biology, to the reproductive piece, and what was not as definitional was really what the purpose of adolescence was or what the, what the core competencies were. And so what we began looking at is that across, across really all animal species, that transition from being a juvenile, and we sort of start not with puberty, but sort of with an animal who's already physically pretty grown and is reproductively capable although not reproducing. And from there, because actually many animals are reproductively capable but don't actually reproduce for quite a long time, but from there we just looked at the necessary stages that there are. Across the animal kingdom there are four core competencies, four challenges that you have to face and deal with. For wild animals, if they don't go through those stages of "wild hood," they don't survive. Athena: 18:36 So what are those stages? Barb: 18:37 So first you, an animal, a juvenile needs to learn to be safe. Athena: 18:41 Okay, so stay away from the zombies. [Barb laughs and agrees] Barb: 18:45 Well actually, we're going to, actually in some cases, and this is what's so cool, you have to sometimes go towards the zombies in order to really be protected from the zombies, which is- Athena: 18:55 After the safety period. Barb: 18:55 That's actually during the safety period! Athena: 18:59 Oh! Really? Barb: 18:59 Right, right. Well, I'll go there. So they have to learn to be safe. Social animals, and social animals are mammals, birds, and actually even reptiles, and amphibians, and fish. So social animals have social brain networks and they need to learn how to engage with other members of whatever the group is. So there's a social, um, social learning function. The third is sexuality, is understanding the language of courtship and sexual communication. And, um, and this is really very important because, you know, in our species, sex-ed is all about- Athena: 19:40 Well, and I mean you're saying that, but I have a feeling that there's some people who never go through that final stage. [Both laugh]. They might have sex, but they might not learn the language of sexual communication, right? Barb: 19:52 Which by the way, yes, it is a problem on lots of levels, including, just to be a little bit serious for a second, including all of these modern contemporary challenges around around consent and coercion and understanding that if you look actually at animal sex ed, sex ed in the wild, young animals from the earliest stages are learning these subtle, complex, how to understand and transmit and respond. And courtship is more than something, you know, you're watching a David Attenborough documentary about, you know, the plumage- courtship is a two way conversation between animals, essentially a conversation, "should we or shouldn't we, are we or aren't we?" And um, that's a whole other conversation but, but the, point- Athena: 20:36 Yeah, that's super relevant though to the zombification issue, right, the control and autonomy and if you have a bidirectional conversation then you can figure out is this something we're both entering into that is in both of our interests, or at least at the moment, we think. [Athena laughs, Barb agrees] Barb: 20:54 Yeah, totally, I mean like one of the most interesting ways of thinking about, I think, I mean since the roots of all human behavior can be found in our animal ancestors and I think there's more to be found there than we have, I know that, again, because of human exceptionalism and a tendency to assume that we are more different than we are the same. But if you even look at your self, if you look at fruit fly courtship, right? So, um, the male, you know, the male approaches and puts on a limb on the female who then, and then based on how she responds to that, um, it determines what he's going to do next, whether it will be an initiation of the next step. And so there is this, so even between flies you have this back and forth and she has part of her brain, some neurons that is processing whether she wants to accept the offer. So there's this whole thing, it's not just a couple of flies, it's two individuals who are gonna, who are talking about whether it's going to happen or not. And what's really interesting in terms of the zombie, the zombification because you know this, there's this, there has been, I've heard this idea that, you know, you hear that well, teenagers are sex trays and they're in a hormonal storm and all this, this is, you know, it's trite. It's underexamined, but sort of with that as a very low bar for understanding sexuality in emerging adults, we then can look at animal courtship and see some really interesting examples of, of how things happen. There is, for example, coercive sexuality among animals. There's no question that, um, there is sexual coercion, but there's also, you do begin to see the building blocks of human consent. And yes, they are. I mean that sounds maybe provocative or controversial, but they are the building blocks of consent. [Athena agrees] There was a study, this Brazilian biologists did this amazing study where she looked at, um, these turtles and she looked at the male- so when the males advanced on the females to, you know, to have sex or to express their interest, in this study, the females, accepted those overtures, the primary overture, that first overture only 14% of the time. So then 86% of the males went away. Of the 86% that were rejected, 96% understood, gain, I'm going to be, I'm going to personify, forgive me, understood that no means no, only 4% persisted. So, you know, there's a million factors, what's going on in the ecology and all these things, but it's just interesting to look at a Brazilian turtle and to see that this conversation of understanding, of sending signals, receiving signals, um, responding, probably learning what they mean. I mean, I don't know who the 4% were that persisted, were they- but anyway, so, so once you begin thinking, "oh my gosh, in turtles, really, in fruit flies, these conversations are happening?" Now all of a sudden, the idea that, and by the way, even Drosophila have a stop- there's, you know, if there's a negative signal, there's this, there's a stop and go, right? This is, it's not automatic as the, Michael Crickmore who, and his... gosh I forget her full name, they have a lab together, [inaudible]. He says they're not little robots. It's not like once they start, they're just going to go to copulation, like, there are signals and they, they're- Athena: 24:55 They're not sex zombies. Barb: 24:56 They're not sex zombies! Even Drosophila aren't. So, it's just sort of like, let's, let's try to think of ourselves more like Drosophila in terms of this like, and begin thinking about learning and, just because there's sexual desire, even Drosophila, it's like a balancing of desire and restraint. Desire and restraint, not zombified pursuit regardless of what's coming back. [Athena agrees] But anyways, and the final thing that adolescents need to master across the animal world, they need to learn to be self reliant and you know, find food for themselves and all of that. [Athena agrees] But the safety part was what we have to talk about. Athena: 25:39 Yeah, so tell me about what you mean by like they have to learn to be safe, but that can involve actually not being safe, that paradox. Barb: 25:48 Right. So one of the first things when, this is several years ago, when I started thinking about adolescence and risk and all this, so you- Athena: 25:57 So are you going to explain like basically why it's mostly adolescents who like Zombie movies, essentially? Barb: 26:03 Yeah, we're getting, we're going get to that. [Athena laughs] Athena: 26:06 And everyone else who loves Zombie movies, they're really just, they haven't even left that first stage of development. [laughter] Barb: 26:14 You know, it's funny. I should probably get the statistic on like who buys tickets for scary movies, that does really seem like, it does seem like I would tip in that direction. [Athena laughs] What did I know about- okay, so first of all, the grim statistics, okay? And it's, it is grim. Like, between being a child and being a young, like person in your twenties, there's a doubling, like it's reported as a 200% increase in mortality. It's a very, very dangerous period for human beings. Between adolescence, essentially from moving from childhood mortality risk to early adult- talk about, the risk of dying increases significantly. Now that's been explained to me. A lot of really smart people have been looking at that. And um, a lot of that, first of all, most of that is accidents and most of those accidents are car accidents, followed by suicide and homicide and, and then some other factors. But, um, just starting with accidents first. So, a lot of the really good science that's looked at why adolescents are so accident prone has looked at unique aspects of adolescent neurobiology. And we've learned that actually the, yeah, that the, the restraint centers or the executive, the executive processing centers, that prefrontal cortex that sort of regulates and contains those things come online later than other brain functions, and so that may lead to impulsivity and a lack of judgment. And in fact, some of the characteristics of adolescents, broadly, are that they tend to be, some of them at least, tend to be more impulsive and more more um, sensation seeking. They may experience the pleasure rewards of risk taking more. They also have brains that, their threshold for risk decreases- well they're willing to take more risks when they're with peers. I mean and these are all kind of brain-based. Athena: 28:21 We love brains on this podcast. Barb: 28:23 Neurobiology! But here's, but here's the thing, I would say neurobiology is fantastic and it's transformed lots of things. Right? Before neurobiology we were, we were talking Freudian, you know, we were explaining things based on whatever, potty training and whatnot, and psychology and psychiatry and neurobiology, really, really valuable. But I would say that ecology is actually as important as neurobiology or psychology, that those are sort of inside out ways of understanding things. But ecology really is outside. Athena: 29:02 So how does ecology help us understand what's going on in adolescence and in particular like connecting it to the work that you've done looking across species at adolescence? So, how does ecology give us these answers? Barb: 29:16 So the first thing that I needed to know to sort of see, hey, can we move past this inside out approach to this outside in approach is first of all, do nonhuman animal adolescents also suffer high rates of accidents and risks? And it turns out they do. I did a very large systematic review of animals who are, we would call them, I call them animal adolescents. They're leaving home, they're called dispersing animals. They're old enough to leave the natal, you know, den or borough. Or fledgling birds, so these are birds that are old enough to be off, right? And in those first days and weeks out of the nest, it's the most dangerous period of their lives. They are inexperienced. They are, first of all, easy prey. So a lot of predators know to look out for newly unchaperoned young who are big enough to be on their own but, they're, they're just, they're big and dumb basically. And so they are, they're easy prey. So that's one piece, so young animal adolescence have high rates of death in those early phases. And by the way, if you look at the early days of driving, when kids start to drive those first, that first year is the riskiest, right? And it's, and the more experience someone has behind the wheel, the safer they become so every- Athena: 30:40 So there's some sort of parallel between like adolescent nonhuman animals kind of going out and learning to deal with predators and be safe and then adolescent humans who are learning to drive and keep themselves safe from other cars that could hit them and- Barb: 30:54 [Barb agrees] It's an imperfect parallel, but it's there. But anyway, so in terms of why- so if you were to just look at animal adolescents and the things that they do that put them in danger and all you knew is neurobiology and psychology, if you didn't know about ecology, you might say, "oh, well, maybe they have like, underdeveloped prefrontal cortex," but then you're like, wait a minute, do they have a human prefrontal cortex? Right? So then it, it's confusing. Okay. So how to explain it? So this is where you put on your ecologists hat or your animal behaviors hat and you start saying, "hmm, so why are- what are they actually doing?" And there are two really amazing, I found really, transformational insights. The first is that some of what adolescent animals are doing is just trying to stay alive. It looks like risk taking, but actually it's not. So, if you look at a group of birds, and there have been a lot of experiments that have looked at their dominance and their subordinance and it turns out, when you are a young member of a flock- age is really an important rank criteria so the older are you typically become more dominant. So adolescents are typically subordinates. So the bird biologists look at these groups of dominant and subordinate birds, right? And they do this thing where they, the birds are all feeding in a little field and then they bring in this predator, this pseudo-predator. And what are the birds do? They all, of course, go into the bushes to hide. And that's when the experiment begins. Okay. They then start to watch which of the birds will come out to start feeding first. Athena: 32:34 So if you did this, like in a crowd of high schoolers, you'd like bring the zombie out all "raaaaah" and everbody would go hide, right? And then who would come out first? [Barb agrees] It wouldn't be the teachers, it would be the adolescents. Barb: 32:48 Yeah and I love where you're going with it, I'm gonna make, I'm gonna make the metaphor work a little bit better. That Zombie has a big, um, is it Halloween? The Zombie has a lot of candy, it's food! Athena: 32:58 Oh so it's like a pinata zombie! Barb: 33:02 It's a pinata zombie! All right, so they watch to see- and of course now the birds knows whether the predator is gone or not. It's an unknown. And what turns out is that the subordinates come out first and the subordinates, and there's theories about it, but one of the primary theories is that subordinates are... you know, dominant birds eat the food, when there's food and often restrict access to subordinates, the subordinates are hungrier. And the birds, these younger birds presumably have to come out and start eating because they don't want to starve. So, in other words, need is driving them to do- it looks like risk-taking and if you don't know what's happening, you might think, well, maybe it's just neurobiology. And actually it's amazing because what that means is that being a subordinate forces you, not having as many resources, forces you to do things that would put yourself in jeopardy that can be misinterpreted as just risk-taking. [Athena agrees] The Urban Institute, which is this, you know, think tank that LBJ founded in the 60's for the war on poverty, they published a study in 2016 and they looked at food insecurity among teenagers in America. And between, in 2016 there were almost 7 million, 10 to 17 year olds in the US who have regular food insecurity and many of them steal, sell drugs and even engage in sexual transactions to eat. To eat. And so again, if you, if you're not thinking like an ecologist and you don't really see this pattern, you can misunderstand the motivation. Athena: 34:42 Right, and you can miss that the situation that they're in is really the problem. It's not that there's something wrong with their brains. Barb: 34:49 Correct. It's the ecology which then gives us this amazing opportunity. If we as a society want to take that opportunity to actually address that by changing resources. [Athena agrees] But that's one, one reason. Athena: 35:05 One, one potential reason why you might approach a situation where there's a predator is because there's some potential benefit to be gotten. And if you're subordinate, you might actually need to get that more, right, than if you're more dominant. Barb: 35:19 The dominant's been fed. Their risk of starvation is not as not as near. And actually it also works for the dominants to keep the subordinates hungry. This is a little political, but it's true because if the subordinate goes out and there is a predator there, then A) they now know that, they're watching from the bushes, and B) now the predator has eaten. Athena: 35:42 That's so dark. Barb: 35:43 It's dark. Yeah. It's not exploitation, it's not exploitative zombies. Athena: 35:47 Well, it's like they're making the subordinates zombies if they are keeping them more hungry than they would otherwise be. Right? Barb: 35:54 Yes, that's actually true. And you know, as I think about it, everything is a zombie because when there is suppression and hunger, this leads people to do things that they wouldn't do otherwise. Hunger zombifies people. [Athena agrees] Need, oh my gosh. But the other behavior that you see adolescent animals engaging in, which can eliminate risk-taking in human adolescents or the higher accident risk is something that's really, really interesting and uh, it's kind of remarkable. So, if you watch a group of young gazelle, Thompson Gazelle, in Africa, you may see a behavior that surprises you. You may see, like if a cheetah comes, approaches, the expected response and usual response is that the gazelle take flight. But sometimes you can see, you can watch it on video, on Youtube rather, you see a group of gazelle see a cheetah, and you see them actually not only not fleeing but they're standing there looking at them, and the cheetahs are looking at them. There's no question of that. And they actually don't go away from them, they start to approach the cheetahs, and this behavior has also been seen in minnows, certain fish, it's been seen in some bird species, it's seen in meerkats, and it's called Predator Inspection. And Predator Inspection is believed to- it's defined essentially as individuals approaching their mortal enemy and displaying what is essentially morbid curiosity right. [Athena agrees] Now the question is, why the hell are they doing that? Seems like a real- are they just really dumb? Are they going to have a death wish? Um, are they showing off of for their friends? [both laugh] Athena: 37:58 Are they on the pathway to becoming a physician? [laughter] Barb: 38:00 It is kind of incredibly sort of, on the one hand, it seems to be counterintuitive, but- and by the way, when predator inspection happens, they often do it in groups. Like they, it's part of sort of a mobbing behavior. So they come together, but nevertheless- Athena: 38:18 So you shouldn't go to a Zombie movie by yourself, is what you're saying. Go with your friends. [laughter] Barb: 38:22 It's best, yes, go with your friends. If you want, and there's safety in numbers. [laughter] Which is actually, you know, typically in those Zombie movies, it seems to me that when, when the group is separated, it's bad news. Right? [Athena agrees] Athena: 38:39 Never, never go break up. Just stay together! [both laugh] Barb: 38:44 Exactly, do your predator inspection as a team, for sure! But these amazing, these amazing, you know, investigations that look at predator inspection show that yeah, it's true that sometimes predator inspection can cost you your life, but in the long run it actually keeps you safer. So it's a kind of, um- Athena: 39:08 How is it keeping you safer? Barb: 39:09 So, the proximate mechanism, how it's believed to work is that having more information about the thing that's most dangerous to you allows you to navigate risk and, sort of, make better decisions in your future, your near future. Athena: 39:30 So if I'm a gazelle and I know just how fast the fastest cheetah can run, then I know how long I can keep eating this until I run away. Barb: 39:40 Exactly. But there's lots of things. I mean, it's not just like, "oh, cheetah, dangerous. I should avoid." It turns out that cheetahs are dangerous when they're hunting and when they're hungry. But a carnivore who's been fed isn't dangerous at all. And you can see video of prey species walking right past their mortal enemy when they're, when they're sated. So just knowing your predator keeps you safe because it also, you're then not deprived of certain feeding opportunities because you're not overreacting unnecessarily. So the more knowledge you have about your predator and how, how it, how it relates. The other interesting- Athena: 40:22 Know your predator. I mean this totally relates to the zombie issue, right? Because zombies, they're just always hungry and they're always trying to eat you. Barb: 40:31 They're never satisfied? Athena: 40:32 That's the idea. They're just... Barb: 40:35 They never get full? Athena: 40:36 So they;re like a- Barb: 40:37 Teenager. [Both laugh] Have you ever had a teenage son? Try keeping the refrigerator full! [more laughter] I didn't know that. Athena: 40:45 Yeah, so they have, so they're like a predator that no matter how much you inspect them, you can't know when they're full. [Athena laughs] Barb: 40:52 Okay so that is so- so then what if you- this is a really good point. So if you're not going to get information about when a predator, like about- because satiety, if variation in satiety doesn't correlate with the danger, then there's other information. So some of the other information you could get would be what they smell like. Right? Athena: 41:13 Zombies smell really bad apparently. [laughs] Barb: 41:15 So there you go, now you know what they smell like, you know a little bit what they, um, maybe what they sound like. You also are looking potentially at the relationship between the different- the age of the predator who's there. Um, you're just picking up, you're doing a risk assessment. [Athena agrees] And what seems to be interesting is that in studies that look like fish, young fish, who predator inspect, and they often do it together but even sometimes by themselves, when they come back and the, the group that they come back to, even if they haven't themselves predator inspected, that whole group becomes safer because there's social transmission of that knowledge that came from predator inspection. And this is not just in fish, but that being deprived of that sort of peer influence, that peer knowledge is actually risky. Having social social information about danger is very advantageous, which is sort of interesting because as a parent, like my kids are nearing the end of adolescence, depending on who's defining it, right, I would've thought, "well, I want my kids to be friends with like the nerdiest, most unworldy-" [laughter] You know, but it may be that when it comes to being safe, there's a lot of information that peers who have had some experience can offer. Athena: 42:47 Right. So, I know we have just have a few minutes left. I definitely want to get to the question about what is your version of the morbid curiosities on the apocalypse? Like if every one morbid curiosity, you just kick it up a few notches. What does the world look like? Barb: 43:09 Oh, so if everyone is, let's just say that predator inspection is moving toward the thing that could kill you the most. Right? Athena: 43:26 You're like driven to get information about these things that are really dangerous, but to a point where you're taking way more risk maybe than is wise. Barb: 43:35 So, I mean, and I love that question. Um, so I would say two things come to mind. One would be that if you have a big group with a common enemy and the group comes together to approach the enemy, that's called mobbing. And that is a well known behavior in lots of animals from mammals to birds to fish. And that is, that is one of the ways that you can overcome real danger. You can actually literally take the thing which can completely smite you, because it's a zombie and you're just a little nothing, but you bring, if everybody is coming up to the zombie, then it changes. It's like the French revolution. [Athena agrees] So that's maybe the way that you do ultimately defeat the zombie is by coming together, and what's really interesting is that sometimes birds come together who are not from the same species. It's called a mixed flock, a mixed flock, mixed species flock but they have a shared enemy and they mob that shared predator together. Isn't that interesting? Athena: 44:53 Okay, so then do you think we can get like all of the species of the world to work together in the zombie apocalypse and mob all the zombies? Barb: 44:57 I think it's possible but I definitely- I mean that's the ultimate goal, to get all the species, but even if we can get our species together! [both laugh] That may be the taller order, actually. But yeah, the idea that there's safety in numbers and that, in fact, the best way to inspect, to predator inspect is with a team. Athena: 45:18 And if you're in a team then maybe is it actually okay to be more willing to inspect so you can like actually have your morbid curiosity enhance when you're with the group. Barb: 45:30 Yeah! Which takes me to the second one. I love this question so much because one of the things that's really interesting and unexpected about, it's not just adolescent animals, but let's just focus on adolescent fish for example. That, you know, the expression, you know, it was FDR that said "there's nothing to fear but fear itself," right? So it turns out that certain fish, I believe it's sticklebacks, and sticklebacks are part of- most fish species don't get, most fish don't get in parental care, right? It's like lay 'em and leave 'em, lay the eggs and they're gone. But in 20% of species there actually is parental care, and very often it's paternal. It's the dads, the fathers are taking care of the, of the eggs and then the little fry and whatnot and it's really interesting, is there's a lot of interest in well, how does a parent's behavior and father's behavior change the behavior of its offspring? And it turns out that anxious father's, anxious stickleback fathers who've had like lots of really scary experiences with predators actually have offspring in some of the experiments who have more, they call it anxiety. Their word. And you'd think, well, that's a good thing because then they, they're more cautious and sometimes it's a good thing, but it turns out fish anxiety actually, the anxious behavior increases the chance of a fish being eaten by a predator. I mean, they're certain that the anxiety causes a certain jerking movement, which it's like instead of immediately getting away, there's this delay. So the anxiety itself is fitness reducing. I mean, not always, but in this, the study that I'm specifically referring to. So, and it's interesting because it's also if you're raised by a parent, a father stickleback who was raised in a really dangerous environment where there are predators all the time and now you're in an environment where, like, all the predators are gone, you don't need to be so scared. Maybe you're, you're not getting opportunities. So that's a negative too. So the idea that anxiety and fear has a cost. I mean, sometimes it's the best thing in the world, but sometimes it's not. So one of the things I, in terms of the zombie apocalypse and morbid curiosity is that if you have these groups of let's say, adolescents who are coming to inspect and everyone's so scared because it's a zombie [spooky voice]. [laughter] It's the zombie apocalypse! And now it's like "oh my god." [mimics looking at zombie] It's sort of like, it's not so scary after all. I mean there's some danger but yeah, I see what we have to do. [Athena agrees] They're really not very fast and- Athena: 48:23 They're just hungry! [both laugh] Barb: 48:23 It's just hungry and they don't look very steady on their feet, it's like you start to sort of like, yeah, there's some risk here, but I'm not that scared I, there's strategy. So, so maybe, um, morbid curiosity and kind of collectively coming toward the thing that scares us the most can not only bring us together, but also help us put some of the things that we think are so scary into perspective, which will ultimately keep us safer. Athena: 48:53 I love that, Barb. Thank you so much for sharing your brains with us this episode. Outro Music: 49:01 [Outro Music] Athena: 50:18 Thank you to the Department of Psychology and ASU in general for supporting Zombified, especially The Interdisciplinary Cooperation Initiative in the Lincoln Center for Applied Ethics. Also, thank you to my lab, the Aktipis lab, otherwise known as The Cooperation and Conflict Lab. Thank you to the Zombie Apocalypse Medicine Alliance. And if you are looking for us on Twitter and Instagram and Facebook, we are Zombified Pod, on Patreon we're Zombified, and our website is zombified.org. Please consider supporting us, we're an educational podcast, we have no ads. Just $1 a month will make a difference in terms of helping us to make this podcast happen. Thank you also to all of the brains that help to make this podcast: the extremely talented Tal Rom, who does our sound, to Neil Smith, who does all of our illustrations, to Lemi the awesome artists behind the song"Psychological," to everyone in my lab who helps out with so many different aspects of this podcast, and actually to everyone who has ever shared their brains with me. You are a part of this podcast somehow. Athena: 51:33 Speaking of brain sharing, at the end of each episode I share some of my brain, I offer a story or some sort of connection to my work or just a wild speculation about something. And so for this episode I wanted to talk about how excited I am about this idea of morbid curiosity and what it can do for us. So one of the things that I really loved is how in a way, Barb kind of embodies morbid curiosity. You know, she's curious about all of these things that are threats to human health and she is looking at that across organisms and looking across organisms at why organisms are fascinated by things that are threatening, too. And so when she talked at the end about how morbid curiosity can be this forced to bring us together, I found that really inspiring. So this idea that if we are able to approach the things that scare us together, then that can put things into perspective and ultimately keep us safer, because if we're doing that together, then we're gathering information together and in that process of gathering information, we are actually safer because we're doing it together. And this is kind of the whole point of the Zombie Apocalypse Medicine Alliance and the Zombie Apocalypse Medicine Meeting to kind of leverage our collective morbid curiosity so that we can better understand the threats that we're facing, whether those are, you know, infectious diseases, or getting hijacked neurally by social media, or how to actually deal with disasters when they happen. So all those things, I think they're less scary when we approach them and we examine them together and it's more fun with morbid curiosity. Thank you for listening to Zombified, your source for fresh brains. Outro Music: 53:52 [Outro Music]