WEBVTT 1 00:00:00.280 --> 00:00:02.399 Oh hey, it's your sister's high school friend who is 2 00:00:02.439 --> 00:00:04.960 eating frozen custard in the background of a hometown date 3 00:00:05.000 --> 00:00:08.000 on The Bachelor. Not really. Ali warret back with an 4 00:00:08.039 --> 00:00:11.960 episode You're gonna hate Maybe I dare you to listen. 5 00:00:12.400 --> 00:00:17.359 It is packed with bananas information about the human mind 6 00:00:17.600 --> 00:00:22.280 and psyche, and about fear and power and social contagions 7 00:00:22.800 --> 00:00:27.920 and delightful squeals. But it is absolutely not soothing whatsoever. 8 00:00:28.280 --> 00:00:30.920 Don't fall asleep to this. Don't play this with your 9 00:00:30.960 --> 00:00:34.240 grandpa recovering from surgery on the couch next to you. 10 00:00:34.759 --> 00:00:36.759 Don't turn to me if you're having anxiety about your 11 00:00:36.799 --> 00:00:40.359 kolonoscopy prep. Not the episode, not the episode for that 12 00:00:40.439 --> 00:00:42.719 at all. This one is going to tear at the 13 00:00:42.759 --> 00:00:46.719 fabric of your sanity. And this ologist offers so much 14 00:00:46.759 --> 00:00:50.399 cocktail party trivia. Hoo boy. So he did his undergrad 15 00:00:50.439 --> 00:00:53.079 and animal behavior and got a master's in psychology and 16 00:00:53.159 --> 00:00:56.840 a PhD in zoology, a post doc with primates at 17 00:00:56.960 --> 00:00:59.640 Rockefeller University, and is now a professor in the Department 18 00:00:59.679 --> 00:01:02.320 of peche Collogy at Emory, where he has been since 19 00:01:02.439 --> 00:01:05.400 nineteen eighty four. And if you have seen an article 20 00:01:05.439 --> 00:01:08.599 about the study of human screams. It is likely that 21 00:01:08.680 --> 00:01:11.359 this person has been quoted, So here we go. But first, 22 00:01:11.400 --> 00:01:13.959 thank you to all the patrons who submitted wonderful questions 23 00:01:13.959 --> 00:01:16.120 for this You can join the patreon at patreon dot 24 00:01:16.120 --> 00:01:19.280 com slash ologies for a buck a month and submit questions. 25 00:01:19.560 --> 00:01:22.680 Also thanks for spreading the word about the show, telling friends, 26 00:01:22.680 --> 00:01:25.599 and leaving reviews, which helps so much. This one this 27 00:01:25.640 --> 00:01:28.640 week holy shit, so worth it. I'm going to put 28 00:01:28.719 --> 00:01:31.159 the review at the end of the episode as the 29 00:01:31.239 --> 00:01:34.359 secret I want to read the whole thing anyway, Onto screamology. 30 00:01:34.519 --> 00:01:37.519 So the word scream it's said to come from a 31 00:01:37.519 --> 00:01:42.879 Scandinavian term meaning to terrify or cry aloud, so vocalization 32 00:01:43.239 --> 00:01:47.480 via forced air, and the term screamology was coined in 33 00:01:47.480 --> 00:01:51.560 the press years ago about this guy, so I reached out. 34 00:01:51.799 --> 00:01:55.040 Luckily we had some help in booking him. We talked 35 00:01:55.120 --> 00:01:57.799 before the holidays, on a day when Emory was having 36 00:01:57.840 --> 00:02:02.079 some giant fundraising drive on campus, but luckily his office 37 00:02:02.400 --> 00:02:05.200 appeared to be soundproofed, so we warmed up our voices 38 00:02:05.239 --> 00:02:09.960 and chatted about movie screams, which animals scream, the difference 39 00:02:09.960 --> 00:02:15.039 between yelling versus screaming, happy screaming, scream queens, screamed kings, 40 00:02:15.360 --> 00:02:19.479 the decibels and distance of screams, screaming in your nightmares, 41 00:02:19.800 --> 00:02:23.680 boy bands, dictators, death metal, and more. With plenty of 42 00:02:23.759 --> 00:02:26.000 examples in here that we try to keep quiet, but 43 00:02:26.039 --> 00:02:31.280 they're in there, so get ready with primatologists, research psychologists, 44 00:02:31.319 --> 00:02:36.280 and one of the world very few professional dedicated screamologists, 45 00:02:36.479 --> 00:02:58.319 doctor Harold Gazulas. Once again, that name. 46 00:02:58.199 --> 00:03:04.000 Is Harold Kazoulis. It's a Greek name, three syllables, so 47 00:03:04.080 --> 00:03:07.639 pretty simple for a Greek name, and he him. 48 00:03:08.039 --> 00:03:10.439 Kind of like someone who's been a victim of a 49 00:03:10.520 --> 00:03:16.000 kazoo theft and is now kazouls Hi Ali, Hi, you 50 00:03:16.080 --> 00:03:16.759 sound great. 51 00:03:17.120 --> 00:03:21.719 Well, let's hope. I was almost at heart attack coming 52 00:03:21.719 --> 00:03:25.560 down here. Atlanta traffic is notorious and Friday afternoon is 53 00:03:25.560 --> 00:03:27.599 the worst, and it just turned out to be one 54 00:03:27.599 --> 00:03:31.120 of those worst case scenarios. Oh no, And I was 55 00:03:31.639 --> 00:03:34.800 rushing to get down here and managed. And then I 56 00:03:34.840 --> 00:03:38.680 discovered that the campus is a very noisy place today 57 00:03:38.759 --> 00:03:42.520 because Emory my University, is kicking off their big capital 58 00:03:42.639 --> 00:03:46.599 campaign and so there's music playing everywhere. 59 00:03:46.639 --> 00:03:46.840 Now. 60 00:03:46.960 --> 00:03:51.159 Fortunately, my office seems to be tucked away just sufficiently well, 61 00:03:51.520 --> 00:03:54.719 so it's not really noticeable. I don't know if you 62 00:03:54.759 --> 00:03:56.120 can hear anything in the background. 63 00:03:56.240 --> 00:03:57.159 No, I can't at all. 64 00:03:57.599 --> 00:03:59.039 Okay, good, good? 65 00:03:59.120 --> 00:04:01.879 Now is does your office have to be well insulated 66 00:04:01.919 --> 00:04:04.560 in case there are screams or is it just lost? 67 00:04:04.639 --> 00:04:10.759 Well, well, my lab is more isolated, and yet the 68 00:04:10.800 --> 00:04:14.439 story goes that people walk by and will hear some 69 00:04:14.520 --> 00:04:18.519 of the screams that we're listening to and talking about 70 00:04:18.560 --> 00:04:22.800 within the lab with my students and wondering what's going on, 71 00:04:22.920 --> 00:04:26.680 and so they have to hear. Oh, that's just doctor 72 00:04:26.720 --> 00:04:31.199 Gozulis's scream research. Don't worry about it, don't panic, don't 73 00:04:31.240 --> 00:04:32.720 run for the hills. 74 00:04:33.160 --> 00:04:36.120 How long have people been calling you a screamologist? 75 00:04:36.720 --> 00:04:42.360 Only quite recently within the context of ologies, I would 76 00:04:42.519 --> 00:04:46.160 first be a biologist. That's where my degree is in 77 00:04:46.199 --> 00:04:50.879 and it's actually in zoology my PhD. And I'm working 78 00:04:50.920 --> 00:04:55.879 in a psychology department and have been for thirty seven years. 79 00:04:56.000 --> 00:04:59.839 If that can actually be the true, Wow, you're it, Emory. Yes, 80 00:05:00.199 --> 00:05:03.480 And my training is in ethology, which is the study 81 00:05:03.480 --> 00:05:07.040 of animal behavior, and the animals I work with mostly 82 00:05:07.120 --> 00:05:11.360 are non human primates, so technically I'm a primatologist. As well. 83 00:05:11.600 --> 00:05:14.160 Oh, you're so many ologies underweos. 84 00:05:14.240 --> 00:05:17.920 I have a lot of ologies. But I was talking 85 00:05:17.959 --> 00:05:20.279 to a reporter I don't know a year and a 86 00:05:20.319 --> 00:05:23.399 half ago. He said, wow, is it okay if I 87 00:05:23.480 --> 00:05:26.079 refer to you as a screamologist, And at the time 88 00:05:26.120 --> 00:05:31.439 I thought, hmm, that's a little a little off, but 89 00:05:31.879 --> 00:05:34.519 go ahead if you'd like. If it's if it's something 90 00:05:34.560 --> 00:05:38.439 that would enhance your piece, please screamology would be fine. 91 00:05:38.720 --> 00:05:42.399 Ah well, it's lucky for me because after that came out, 92 00:05:42.439 --> 00:05:45.240 I had a lot of people screencapping it and saying, 93 00:05:45.399 --> 00:05:47.959 there's a screamologist. You have to find him, Please ask 94 00:05:48.040 --> 00:05:50.800 him everything, Please find him right out. So yeah, I've 95 00:05:50.839 --> 00:05:52.160 had my sights on you for a while. 96 00:05:52.399 --> 00:05:55.199 Oh well, that's cool. And I must say that my 97 00:05:55.360 --> 00:05:58.639 daughter in law is one of your biggest fans. When 98 00:05:58.680 --> 00:06:03.720 I mentioned the possibility of this interview, she was so excited, 99 00:06:04.040 --> 00:06:05.680 So it's really cute. 100 00:06:05.800 --> 00:06:08.120 So yes, thank you for vouching for a Sam. We 101 00:06:08.360 --> 00:06:10.600 absolutely owe you on. And I know that you would 102 00:06:10.600 --> 00:06:13.519 expect this episode in October everyone, but right now it's 103 00:06:13.600 --> 00:06:17.439 January and it's cold, and the snow is dirty and slushy. 104 00:06:17.759 --> 00:06:19.959 My roof is leaking. Is it a good time to 105 00:06:20.040 --> 00:06:24.319 bellow your throat raw? What would you say time of year? 106 00:06:25.519 --> 00:06:29.240 As a culture people scream the most. Do you think 107 00:06:29.319 --> 00:06:32.480 it's in the summer when people are getting squirted with 108 00:06:32.519 --> 00:06:35.720 water guns? Is it during haunted house season? Is it 109 00:06:35.720 --> 00:06:38.759 when they get their bills after the holidays? When do 110 00:06:38.839 --> 00:06:39.920 we scream the most either? 111 00:06:40.040 --> 00:06:42.439 That is very interesting. I don't think I've ever had 112 00:06:42.439 --> 00:06:47.160 that question, But I would say people in general, you 113 00:06:47.240 --> 00:06:51.480 probably hear more screams outside in the summer, and they 114 00:06:51.480 --> 00:06:54.839 come mostly from children because they're at swimming pools and 115 00:06:54.879 --> 00:06:59.199 playgrounds and just a lot of social interaction. As any 116 00:06:59.240 --> 00:07:04.040 parent and most adults can appreciate and know children just 117 00:07:04.079 --> 00:07:10.439 scream all the time they get them together. So I 118 00:07:10.439 --> 00:07:14.560 would say summer, I think probably that's what I would think. 119 00:07:14.759 --> 00:07:17.480 Yeah, that was my hypothesis. I'm glad that it holds 120 00:07:17.480 --> 00:07:21.800 a little bit of water. But what is a scream 121 00:07:21.920 --> 00:07:25.959 and who does it? What animals can we classify as screaming? 122 00:07:26.000 --> 00:07:27.879 What's the difference between a call and a behavior and 123 00:07:27.920 --> 00:07:28.319 a scream? 124 00:07:28.480 --> 00:07:33.439 Right, Screams are a particular category of vocalization in the 125 00:07:33.480 --> 00:07:36.319 repertoire of many different species, and we can come back 126 00:07:36.360 --> 00:07:39.480 to that in a bit. But you know, there isn't 127 00:07:39.519 --> 00:07:44.360 a precise and absolutely formal and totally accepted definition of 128 00:07:44.399 --> 00:07:49.319 a scream, but there are key features of screams, so 129 00:07:50.160 --> 00:07:53.439 they in terms of the length of a particular utterance, 130 00:07:53.800 --> 00:07:57.439 it would be from half a second to about a 131 00:07:57.480 --> 00:08:01.560 second and a quarter, maybe stretching it to two seconds, 132 00:08:01.600 --> 00:08:06.759 but anything beyond that begins to sound unnatural. Screams are 133 00:08:06.839 --> 00:08:13.519 high pitched and there are often harmonics around the fundamental frequency, 134 00:08:13.560 --> 00:08:17.839 but screams also break into chaotic noise as well, so 135 00:08:18.000 --> 00:08:21.519 they're not pure tones. Although some people tend to produce 136 00:08:21.560 --> 00:08:26.079 screams that are more tonal and frequency modulated, and others 137 00:08:26.160 --> 00:08:30.240 have more noisy, harsh sounding screams. So does some individual 138 00:08:30.279 --> 00:08:35.080 variation as well. There's an acoustic parameter that's referred to 139 00:08:35.120 --> 00:08:42.320 as roughness. It's rapid variation and modulation of amplitude fluctuation 140 00:08:42.480 --> 00:08:46.519 in a particular range is characteristic of screams, and there's 141 00:08:46.720 --> 00:08:50.120 one group of researchers, Luke Arnall has claimed that in 142 00:08:50.159 --> 00:08:55.879 fact it is definitive that is what inherently categorizes a scream, 143 00:08:56.240 --> 00:08:59.919 but subsequent research has shown that other kinds of human 144 00:09:00.120 --> 00:09:04.320 vocalizations also have this characteristic of roughness, and so it 145 00:09:04.360 --> 00:09:07.000 can't be exclusive to screams. 146 00:09:07.679 --> 00:09:09.639 You know what, Let's go through a few quick vocal 147 00:09:09.679 --> 00:09:13.440 basics here, shall we. So frequency of the sound waves 148 00:09:13.440 --> 00:09:16.720 determines their pitch, and that is measured in something called hurts. 149 00:09:17.120 --> 00:09:20.000 But the amplitude is the height of the sound wave, 150 00:09:20.320 --> 00:09:24.840 and that determines the volume, and amplitude is measured in decibels, 151 00:09:24.840 --> 00:09:27.399 which you've probably heard of. So the roughness, what does 152 00:09:27.440 --> 00:09:31.120 the roughness mean? That is the rate of change in volume, 153 00:09:31.480 --> 00:09:34.720 And the more the volume fluctuates in a scream, even 154 00:09:34.799 --> 00:09:38.559 though it seems imperceptible to you, it'll land is more 155 00:09:38.720 --> 00:09:42.440 shrill and it'll probably freak you out more. Infants crying 156 00:09:42.759 --> 00:09:47.759 exhibit roughness, as does a human whistling, just in case 157 00:09:47.799 --> 00:09:50.200 we've ever heard either of those and just wanted to 158 00:09:50.240 --> 00:09:53.440 put on earmuffs and then just descend into a sewer 159 00:09:53.480 --> 00:09:55.559 hole in the middle of the city street when you 160 00:09:55.559 --> 00:09:55.879 hear it. 161 00:09:56.039 --> 00:09:59.759 That's normal. So coming back to your question, we all 162 00:10:00.000 --> 00:10:02.759 I recognized screams. One of the projects that we did 163 00:10:03.320 --> 00:10:07.639 was to play screams and other kinds of vocalizations, including 164 00:10:08.200 --> 00:10:12.639 yells and moans and laughter and even sounds like sneezes, 165 00:10:13.159 --> 00:10:16.039 And it sounds like a simple, silly little project. But 166 00:10:16.320 --> 00:10:20.399 what we were looking to see is whether participants agree 167 00:10:20.600 --> 00:10:24.879 as to what constitutes a scream. And with humans, of course, 168 00:10:24.919 --> 00:10:28.240 we scream in a variety of different contexts. I'm literally 169 00:10:28.519 --> 00:10:31.720 screaming right now, and that we can come back to later, 170 00:10:31.759 --> 00:10:36.399 perhaps because that distinguishes us from other species. I know 171 00:10:36.440 --> 00:10:38.679 that was part of your question what other species scream? 172 00:10:38.840 --> 00:10:42.360 So we were interested to see whether people agree as 173 00:10:42.360 --> 00:10:45.759 to what constitutes a scream. So that's independent of formal 174 00:10:45.799 --> 00:10:48.919 scientific definitions. Do we know a scream when we hear it? 175 00:10:49.480 --> 00:10:55.440 And the answer is very clearly yes. Species that scream 176 00:10:55.799 --> 00:10:59.799 very considerably. In some species of frogs scream. You pick 177 00:10:59.879 --> 00:11:03.960 up the frog and it produces a vocalization that is 178 00:11:04.039 --> 00:11:14.759 clearly scream like wow. Rabbit scream are very popular and 179 00:11:14.799 --> 00:11:20.240 you can probably find it. There are videos of rabbits screaming. 180 00:11:20.840 --> 00:11:22.919 Somebody picks the rabbit out of the hutch, out of 181 00:11:22.919 --> 00:11:29.799 the cage, and it just belts out a scream that 182 00:11:30.360 --> 00:11:32.039 is so human like, and I think it gets a 183 00:11:32.080 --> 00:11:34.279 lot of hits. It gets a lot of clicks because 184 00:11:34.360 --> 00:11:38.039 people just find it so funny that a rabbit sounds 185 00:11:38.039 --> 00:11:40.600 so human like, and goats as well. 186 00:11:40.799 --> 00:11:43.000 Yes, I was gonna say, I've seen videos of goats 187 00:11:43.000 --> 00:11:45.799 screaming and it seems like someone's dubbing over. 188 00:11:45.639 --> 00:11:51.679 An I know. Yeah, yes, it is very deep. That's 189 00:11:51.720 --> 00:11:53.960 the perfect imitation of a goat scream, by the way, 190 00:11:54.440 --> 00:11:58.759 But yes, indeed that that is. They're all human like 191 00:11:58.960 --> 00:12:02.159 and sound like. And what that says is that as 192 00:12:02.200 --> 00:12:07.600 a vocalization type, screams are evolutionarily conserved, so they don't 193 00:12:07.679 --> 00:12:10.759 vary all that much. But people find it surprising that 194 00:12:10.960 --> 00:12:16.080 animal screams sound as much like human screams as they do. 195 00:12:15.480 --> 00:12:19.240 Do they though, Well, yes, according to the Google search 196 00:12:19.320 --> 00:12:22.840 that I started with what animal sounds like? That then 197 00:12:22.960 --> 00:12:26.639 auto filled a woman screaming, So apparently a lot of 198 00:12:26.639 --> 00:12:33.320 people here are red fox and then call the cops. 199 00:12:36.120 --> 00:12:42.559 Barn owlshh, sound like your ancestor coming back from the 200 00:12:42.600 --> 00:12:45.200 grave to haunt you for taking such bad care of 201 00:12:45.240 --> 00:12:49.200 your skin. Even caterpillars apparently will yell their heads off, 202 00:12:49.279 --> 00:12:52.399 as evidenced in this YouTube clip uploaded by Matt C 203 00:12:53.000 --> 00:12:56.559 whomse fingers I'm assuming are the ones in frame gently 204 00:12:56.600 --> 00:13:02.840 squeezing the butt of a neon green moth larvae. But 205 00:13:02.919 --> 00:13:05.440 that air, I learned is likely coming out of spiracles, 206 00:13:05.519 --> 00:13:08.639 so scientifically not a scream. A scream itself is when 207 00:13:08.679 --> 00:13:12.080 air is passed through the vocal cords with greater than 208 00:13:12.200 --> 00:13:16.279 usual force. My friend Workipedia says this can be performed 209 00:13:16.279 --> 00:13:21.039 by any creature possessing lungs, including humans, so larva and spiracles. 210 00:13:21.080 --> 00:13:24.480 I'm sorry, you're just doing some kind of respiratory fart 211 00:13:24.519 --> 00:13:26.720 at anyone who squeezes your butt. I don't blame you, 212 00:13:26.919 --> 00:13:30.879 but yes, according to doctor harr Casulis, screams require a 213 00:13:30.919 --> 00:13:34.240 lot of vocal force and cause the vocal folds to 214 00:13:34.480 --> 00:13:38.639 vibrate in a chaotic, inconsistent way. So that is some 215 00:13:38.720 --> 00:13:41.840 of the what, But onto the why. 216 00:13:41.919 --> 00:13:45.039 And of course, if we want to dive into some 217 00:13:45.080 --> 00:13:49.399 of the sort of evolutionary questions, the original screams and 218 00:13:49.480 --> 00:13:54.320 species like frogs and rabbits probably served as a way 219 00:13:55.120 --> 00:14:01.080 to elude capture by a predator. Predator has you in 220 00:14:01.120 --> 00:14:05.200 its grasp, and it's the last ditch effort in essence 221 00:14:05.639 --> 00:14:10.679 to escape. A loud sudden vocalization could sometimes at least 222 00:14:10.679 --> 00:14:15.600 occasionally startle the predator and give the prey, the victim, 223 00:14:15.759 --> 00:14:20.279 some small chance of escape. And there's also suggestions in 224 00:14:20.320 --> 00:14:25.240 the literature that screams could attract other predators and thus 225 00:14:25.320 --> 00:14:28.480 thwart the efforts of the first predator that's got the prey. 226 00:14:28.840 --> 00:14:33.639 So by screaming, it attracts attention. That's another characteristic of screams. 227 00:14:33.919 --> 00:14:40.000 They definitely attract attention from by listeners. So that's how 228 00:14:40.039 --> 00:14:44.919 screams probably started as one way to defend against predators 229 00:14:44.919 --> 00:14:45.480 and predation. 230 00:14:46.000 --> 00:14:48.960 Okay, but frogs don't gather at the pond, giggle screeching 231 00:14:49.039 --> 00:14:52.840 during water fights, or turn trees into money and then 232 00:14:52.919 --> 00:14:55.879 give that money to other frogs who have created a 233 00:14:55.960 --> 00:14:59.919 haunted pond for them. So what's happening in primate brain 234 00:15:00.440 --> 00:15:00.879 like mine? 235 00:15:01.279 --> 00:15:05.720 But then in the evolution of sociality in species like 236 00:15:05.919 --> 00:15:11.600 monkeys and apes, where complex social interactions are dictated and 237 00:15:11.679 --> 00:15:17.039 governed by vocalizations, screams come to serve another purpose, and 238 00:15:17.120 --> 00:15:21.399 that is to solicit support from your friends, your allies, 239 00:15:21.519 --> 00:15:27.320 your relatives, and especially in the context of dominance interactions, because, 240 00:15:27.440 --> 00:15:30.480 as you might know, in monkeys and apes, it's not 241 00:15:30.600 --> 00:15:34.279 how big, how strong, how tough you are, it's who 242 00:15:34.320 --> 00:15:39.279 you know, and so you have your allies. And in 243 00:15:39.639 --> 00:15:43.440 the monkeys that I've studied in the past and continue 244 00:15:43.720 --> 00:15:48.399 to be interested in, the social relationships are primarily among 245 00:15:48.480 --> 00:15:52.879 females and female matrilineal groups. They're the lifelong residents of 246 00:15:52.879 --> 00:15:55.879 the social group. Whereas the males high tail it out 247 00:15:56.120 --> 00:16:00.360 of the group at sexual maturity and find their way 248 00:16:00.399 --> 00:16:03.320 into another group for mating and to live the rest 249 00:16:03.399 --> 00:16:06.639 of their lives. But the females stay together for their 250 00:16:06.759 --> 00:16:11.480 entire social lives, and they help one another develop and 251 00:16:11.559 --> 00:16:15.879 maintain their dominance positions in the social group. And of course, 252 00:16:15.919 --> 00:16:17.639 if you're going to have an ally, you need a 253 00:16:17.639 --> 00:16:22.519 way to recruit that ally. And so screams again acoustically, 254 00:16:22.559 --> 00:16:26.000 similar to what you see in frogs and rabbits and goats, 255 00:16:26.000 --> 00:16:30.279 and so evolved in a more complex way and diversified 256 00:16:30.320 --> 00:16:34.879 acoustically so that the monkeys can communicate more subtle details 257 00:16:34.919 --> 00:16:38.639 about the fights that they're in. Is the opponent dominant, 258 00:16:38.960 --> 00:16:44.200 is the opponent subordinate? Is the aggression intense or is 259 00:16:44.240 --> 00:16:50.639 it modest and mild? So what we think happened is that, 260 00:16:50.879 --> 00:16:54.240 at least within the context of fights, and what the 261 00:16:54.360 --> 00:16:58.679 scientific literature refers to as agonistic interactions. There has been 262 00:16:58.799 --> 00:17:04.240 diversification to send more subtle and nuanced messages about what 263 00:17:04.400 --> 00:17:06.920 kind of fight and who the opponent is. And that's 264 00:17:07.000 --> 00:17:10.960 information that's pertinent to an ally, a relative, for example, 265 00:17:11.400 --> 00:17:14.359 the mom of the victim or the sister who might 266 00:17:14.440 --> 00:17:18.000 be out of sight, you know, foraging in dense vegetation 267 00:17:18.079 --> 00:17:21.319 or something. But adhere's the vocalization, and of course that 268 00:17:21.440 --> 00:17:24.920 implies that it has to recognize who the screamer is, 269 00:17:25.400 --> 00:17:28.599 and it's very clear that that's the case. It's my daughter, 270 00:17:28.920 --> 00:17:33.039 it's my cousin, it's my aunt, and they come to 271 00:17:33.079 --> 00:17:37.319 the rescue and intervene in a way that is consistent 272 00:17:37.480 --> 00:17:41.160 and appropriate for the kind of fight that is taking place. 273 00:17:41.400 --> 00:17:44.319 That's information that they get through the screams. 274 00:17:44.519 --> 00:17:48.200 I'm learning a lot. And is there something about the 275 00:17:48.599 --> 00:17:52.039 frequency or the amplitude of the sound that hits our 276 00:17:52.079 --> 00:17:56.519 brains differently because of instinct and genetics, or is that 277 00:17:56.559 --> 00:17:59.680 something that really has to be learned by primates from 278 00:17:59.720 --> 00:18:02.359 a age through social connections and responses. 279 00:18:02.680 --> 00:18:06.400 They scream naturally, and even human babies in their first 280 00:18:06.640 --> 00:18:10.880 vocal efforts. Crying is of course distinct and separate from screaming, 281 00:18:11.119 --> 00:18:14.359 But screams can be part of the vocal output that 282 00:18:14.599 --> 00:18:15.880 very young babies produce. 283 00:18:16.359 --> 00:18:19.640 Any new parents out there, maybe you're up nursing at 284 00:18:19.680 --> 00:18:23.200 four am or whatever, just think of your baby as 285 00:18:23.240 --> 00:18:27.799 emitting vocal output, not screaming. Maybe that'll help you not 286 00:18:27.839 --> 00:18:30.359 want to stuff it back into your womb for another year. 287 00:18:30.559 --> 00:18:32.559 I don't know. I have a very old quiet doc, 288 00:18:32.640 --> 00:18:34.640 so I'm not sure how it works. But when it's 289 00:18:34.680 --> 00:18:38.039 a happy child and it's shrieking in delight, just know that, 290 00:18:38.200 --> 00:18:42.680 in doctor Cazulaz's speculation, it's doing that. So that if 291 00:18:42.720 --> 00:18:45.799 a large raptor swoops down and tries to pick up 292 00:18:45.839 --> 00:18:49.599 your small child out of a group of many small children, 293 00:18:49.880 --> 00:18:53.039 and your back is turned, you think, wait, that sounds 294 00:18:53.240 --> 00:18:57.920 like the spine tingling yell of my offspring. So thanks evolution. Also, 295 00:18:58.319 --> 00:19:02.039 do we learn this or is it just hardwired in 296 00:19:02.079 --> 00:19:04.880 our jiggly goopy complex brains. 297 00:19:05.359 --> 00:19:08.279 I don't think you have to learn to scream. Yeah, 298 00:19:08.480 --> 00:19:12.119 The interesting question is whether or not humans have to 299 00:19:12.240 --> 00:19:16.799 learn to distinguish different kinds of screams that we produce 300 00:19:16.880 --> 00:19:21.720 in different contexts. Because, of course, unlike other species, we 301 00:19:22.319 --> 00:19:25.279 as everybody knows, When you point this out, they all 302 00:19:25.559 --> 00:19:33.880 nod and say, sure, humans will scream in fear, pain, aggression, frustration, excitement, 303 00:19:34.319 --> 00:19:38.160 particular forms of excitement like sex, I'll have what she's having, 304 00:19:38.599 --> 00:19:43.920 And in startle situations. Lots of people, including my wife, 305 00:19:43.960 --> 00:19:47.519 will produce a startle scream when she sees a cockroach 306 00:19:47.640 --> 00:19:51.039 or some people with a mouse, or you know that 307 00:19:51.359 --> 00:19:52.119 kind of situation. 308 00:19:52.720 --> 00:19:55.519 So the core of a screamologists job is to figure 309 00:19:55.559 --> 00:19:59.440 out if humans can distinguish screams in different contexts and 310 00:19:59.440 --> 00:20:02.039 to note what the hell is up man. I hope 311 00:20:02.079 --> 00:20:05.920 they collect some kind of huge catalog of screams. That 312 00:20:05.960 --> 00:20:06.720 would be amazing. 313 00:20:07.079 --> 00:20:08.759 And one of the ways that we've done that is 314 00:20:08.799 --> 00:20:12.359 to collect a huge catalog of screams. So we've got 315 00:20:12.599 --> 00:20:16.240 literally a scream library, oh my god, that has been 316 00:20:16.359 --> 00:20:20.559 harvested from the Internet and YouTube, because, of course, as 317 00:20:20.559 --> 00:20:25.000 we know, everybody posts their entire life history on the 318 00:20:25.000 --> 00:20:27.680 internet these days, and so you can see there are 319 00:20:27.680 --> 00:20:33.400 many examples of naturally occurring, real screams that we can 320 00:20:33.519 --> 00:20:35.920 use in the research. And then of course there's the 321 00:20:36.119 --> 00:20:40.880 opportunity to take screams from TV shows or movies and 322 00:20:41.079 --> 00:20:43.559 those acted renditions of screams. 323 00:20:44.400 --> 00:20:48.799 And how has your research changed over thirty seven years 324 00:20:48.920 --> 00:20:52.559 as people have more access to recording devices and platforms 325 00:20:52.559 --> 00:20:53.279 to share them. 326 00:20:53.720 --> 00:20:57.920 Oh gosh, yes, it makes a huge, huge difference to 327 00:20:58.079 --> 00:21:02.200 how the research is done and as possible back when 328 00:21:02.240 --> 00:21:05.880 we started and with my wife and I that began 329 00:21:06.119 --> 00:21:11.279 studying screams when we were postdocs at the Rockefeller University 330 00:21:11.400 --> 00:21:12.000 in New York. 331 00:21:12.559 --> 00:21:17.279 Wait, is this screamologist married to another screamologist? I'm screaming so, 332 00:21:17.440 --> 00:21:21.559 Doctor Sally Gazulis spent time as a behavioral biologist working 333 00:21:21.559 --> 00:21:26.359 with non human primates and also worked with some human primates, 334 00:21:26.559 --> 00:21:27.839 namely Harold. 335 00:21:28.039 --> 00:21:31.000 And we were working with a very prominent primarily he 336 00:21:31.039 --> 00:21:34.599 was a bird researcher, Professor Peter Marler was his name, 337 00:21:35.279 --> 00:21:38.960 very well known animal behaviorist, and he kind of dabbled 338 00:21:39.119 --> 00:21:43.000 in primate vocalizations as well. Again, his prime research was 339 00:21:43.039 --> 00:21:47.720 in bird song and bird song acquisition, but he always 340 00:21:47.720 --> 00:21:50.400 wanted to have some graduate students and postdocs working on 341 00:21:50.480 --> 00:21:55.480 primate vocalizations, and the pair of researchers who had preceded 342 00:21:55.599 --> 00:22:00.440 us in his lab had studied alarm calls in a 343 00:22:00.519 --> 00:22:05.079 species of African monkey called the Vervet monkey. And that 344 00:22:05.160 --> 00:22:10.119 work revealed that this species of monkey had evolved different 345 00:22:10.240 --> 00:22:14.319 kinds of alarm calls acoustically, different alarm calls that they 346 00:22:14.400 --> 00:22:17.759 gave in response to different kinds of predators, and the 347 00:22:17.799 --> 00:22:24.960 primary predators were leopards, marshall eagles, and pythons. Now, those 348 00:22:25.000 --> 00:22:29.839 predators hunt and attack in different ways, they have different strategies, 349 00:22:30.160 --> 00:22:34.079 and thus the response to the presence of one of 350 00:22:34.119 --> 00:22:37.240 those different kinds of predators will be different. So you 351 00:22:37.319 --> 00:22:40.640 can't make do if you're a vervet monkey with one 352 00:22:40.720 --> 00:22:43.160 kind of alarm call. They had to come up with 353 00:22:43.599 --> 00:22:49.240 a system that had different vocalizations in essence associated with 354 00:22:49.279 --> 00:22:50.000 those predators. 355 00:22:50.279 --> 00:22:54.039 So you waltzed into this episode casual, maybe leaned against 356 00:22:54.039 --> 00:22:56.240 a wall and thought, this is just going to be 357 00:22:56.279 --> 00:22:59.079 about horror films. But now you know that monkeys can 358 00:22:59.119 --> 00:23:01.680 straight up talk well if you ask me, But is 359 00:23:01.720 --> 00:23:06.440 it talking? Is it language? So Harold an Ape uses 360 00:23:06.640 --> 00:23:10.720 language to make speech about the history of the perception 361 00:23:11.279 --> 00:23:12.640 of communication. 362 00:23:12.440 --> 00:23:17.640 Dating back to Darwin. In eighteen seventy two, he published 363 00:23:17.680 --> 00:23:21.519 Expression of the Emotions in Men and Animals, and expression 364 00:23:21.599 --> 00:23:24.839 of the Emotions is the key part of that title, 365 00:23:25.160 --> 00:23:30.279 because that is what everybody believed animals communicate about their emotions, 366 00:23:30.720 --> 00:23:35.680 and that remained true, and that's what was the conventional 367 00:23:36.079 --> 00:23:42.119 wisdom about animal communication, that while we humans can with 368 00:23:42.279 --> 00:23:46.279 language talk about the external world and anything we can imagine, 369 00:23:46.759 --> 00:23:53.759 animals were restricted to communicating about their emotions aggression, fear, sex. 370 00:23:55.200 --> 00:23:58.640 But that Vervet monkey work that came out in the 371 00:23:58.880 --> 00:24:02.519 late nineteen seventies in early nineteen eighties revealed that there 372 00:24:02.519 --> 00:24:07.799 were some animals that could use vocalizations to index, to 373 00:24:07.880 --> 00:24:13.319 refer to particular occurrences in the external world, namely the 374 00:24:13.359 --> 00:24:15.359 presence of different kinds of predators. 375 00:24:15.880 --> 00:24:18.880 Wait, so what is screaming and what is a warning? 376 00:24:19.279 --> 00:24:24.319 Is screaming emotional? But alarm calls are informational alarm calls. 377 00:24:24.359 --> 00:24:28.079 People sometimes confuse alarm calls because screams can be alarming, 378 00:24:28.640 --> 00:24:33.279 But in the animal behavior literature, when they talk about 379 00:24:33.400 --> 00:24:37.039 an alarm call, it's a specific kind of vocalization that 380 00:24:37.359 --> 00:24:40.279 refers to the presence of a predator. Whereas a scream. 381 00:24:40.559 --> 00:24:43.519 You can scream when a predator has you in its jaws, 382 00:24:43.920 --> 00:24:47.680 but that's not alerting others about the presence of that predator. 383 00:24:48.000 --> 00:24:52.480 That's again a different kind of evolutionary adaptation to avoid 384 00:24:52.519 --> 00:24:55.519 being the dinner or the lunch of that predator. 385 00:24:55.880 --> 00:24:59.920 So, as a post doc working with monkey screams for science, 386 00:25:00.200 --> 00:25:03.920 Harold was listening for vocalizations that might convey information about 387 00:25:04.039 --> 00:25:07.480 external events. So were they screaming for help? And so 388 00:25:07.599 --> 00:25:10.119 by playing tapes of their alarm calls they can learn 389 00:25:10.200 --> 00:25:12.920 who showed up for whom And hopefully that did not 390 00:25:13.000 --> 00:25:15.720 cause a lot of monkey riffs from just sowing distrust 391 00:25:15.880 --> 00:25:17.279 like a monkey who cried leopard. 392 00:25:17.440 --> 00:25:20.960 Anyway, we've pursued it in different ways with different species 393 00:25:21.000 --> 00:25:25.000 of monkeys. Looked at the difference between males and females, because, 394 00:25:25.039 --> 00:25:28.720 as I mentioned earlier, the males end up leaving the 395 00:25:28.720 --> 00:25:32.279 group that they're born into and they enter a group 396 00:25:32.279 --> 00:25:35.240 and they don't have allies. Maybe they might have a 397 00:25:35.279 --> 00:25:39.720 brother or a cousin who also migrated to that same group, 398 00:25:40.240 --> 00:25:44.640 But it's the females that have these persistent, long lasting 399 00:25:44.680 --> 00:25:49.119 social relationships, and they tend to scream, whereas males drop 400 00:25:49.400 --> 00:25:54.799 screaming from their repertoires as they reach sexual maturity. Really, yes, 401 00:25:55.200 --> 00:25:57.480