WEBVTT 00:00:06.261 --> 00:00:09.300 Hi everybody. I am a comparative anatomist, 00:00:09.300 --> 00:00:11.031 and a comparative anatomist is someone who studies 00:00:11.031 --> 00:00:14.058 the structure of the body of lots of different animals. 00:00:14.058 --> 00:00:16.022 And my favorite animals are whales, 00:00:16.022 --> 00:00:18.435 and I like to study whales because they are so interesting. 00:00:18.435 --> 00:00:20.007 They've adapted to a unique environment 00:00:20.007 --> 00:00:21.373 of living in the water. 00:00:21.373 --> 00:00:22.990 And what I'm going to tell you about is 00:00:22.990 --> 00:00:24.977 how whales make sounds by 00:00:24.977 --> 00:00:28.001 basically farting with their face. 00:00:28.001 --> 00:00:29.571 Now, you know that they do this farting thing 00:00:29.571 --> 00:00:31.735 with their blowhole; they blow out air like that, 00:00:31.735 --> 00:00:33.704 but they also use air in lots of other ways. 00:00:33.704 --> 00:00:35.144 They use it for sound production, 00:00:35.144 --> 00:00:36.703 which is what I'm going to focus on, 00:00:36.703 --> 00:00:38.407 but I also study other things they do with air, 00:00:38.407 --> 00:00:40.408 like how they keep it out of their blood streams 00:00:40.408 --> 00:00:41.528 so that they don't get bubbles, 00:00:41.528 --> 00:00:43.471 which is what happens to human scuba divers 00:00:43.471 --> 00:00:46.021 when they dive and they get decompression sickness. 00:00:46.021 --> 00:00:47.803 But what I'd like to do is start with the story 00:00:47.803 --> 00:00:50.033 of how these animals make these farting noises, 00:00:50.033 --> 00:00:51.726 and that story begins with understanding 00:00:51.726 --> 00:00:53.627 how hard it is to look at whales 00:00:53.627 --> 00:00:56.525 because they live underwater and they're really big, 00:00:56.525 --> 00:00:58.398 so they're hard animals to study. 00:00:58.398 --> 00:01:00.762 And just in this picture, you see that animal in the middle? 00:01:00.762 --> 00:01:03.995 That's a baby whale and it's already the size of a bus. 00:01:03.995 --> 00:01:05.434 When you look at whales, you have to start 00:01:05.434 --> 00:01:07.109 with the top of their head, because their nose 00:01:07.109 --> 00:01:08.747 is on the top of their head. 00:01:08.747 --> 00:01:10.287 It's kind of like a built-in snorkel. 00:01:10.287 --> 00:01:12.497 And they breathe through that because they're mammals 00:01:12.497 --> 00:01:14.136 and mammals breathe air. 00:01:14.136 --> 00:01:16.072 And their nose can actually be opened and closed, 00:01:16.072 --> 00:01:17.776 kind of as if you were to pinch it like this, 00:01:17.776 --> 00:01:19.385 so you can see, it's open in the bottom frame there 00:01:19.385 --> 00:01:20.814 where the red arrows are. 00:01:20.814 --> 00:01:23.137 But not all whales have two nostrils. 00:01:23.137 --> 00:01:25.973 Whales includes the groups of dolphins and porpoises, 00:01:25.973 --> 00:01:28.089 and the dolphins and porpoises, the small whales, 00:01:28.089 --> 00:01:30.357 have only one nostril on the top of their head, 00:01:30.357 --> 00:01:32.356 and they open and close that nostril 00:01:32.356 --> 00:01:35.445 by taking what is essentially an upper lip, like this, 00:01:35.445 --> 00:01:39.135 and turning it back over their nose, like this. 00:01:39.135 --> 00:01:41.242 That's how they open and close their nose. 00:01:41.242 --> 00:01:42.504 So when they make sounds, 00:01:42.504 --> 00:01:44.592 what they're basically doing is a raspberry, 00:01:44.592 --> 00:01:47.920 like [mouth noises], which is kind of like a fart, right? 00:01:47.920 --> 00:01:50.228 Or up in New York we call it a Bronx cheer. 00:01:50.228 --> 00:01:52.003 And the way they do that is by taking 00:01:52.003 --> 00:01:54.404 that big fatty structure of a big fat lip, 00:01:54.404 --> 00:01:56.032 which is, as you can see here in this picture, 00:01:56.032 --> 00:01:58.527 which is a cut through the middle of a dolphins head, 00:01:58.527 --> 00:02:01.102 that big fat lip is that big yellow portion there, 00:02:01.102 --> 00:02:04.542 and they roll it back and forth over the top of their nose 00:02:04.542 --> 00:02:06.014 so that they vibrate it, 00:02:06.014 --> 00:02:07.922 kind of like when you let the air out of a balloon 00:02:07.922 --> 00:02:10.112 and it makes that weird vibration sound. 00:02:10.112 --> 00:02:12.169 So this is what it sounds like when they make their noise: 00:02:12.169 --> 00:02:13.179 [dolphin noise] 00:02:13.179 --> 00:02:14.347 You hear that? It's going to do it again 00:02:14.347 --> 00:02:15.510 when he faces the camera. 00:02:15.510 --> 00:02:17.234 [dolphin noise] 00:02:17.234 --> 00:02:19.300 Sounds like its farting underwater. 00:02:19.300 --> 00:02:20.960 What that dolphin is actually doing though 00:02:20.960 --> 00:02:24.413 is echolocation, which is making these series of pulses, 00:02:24.413 --> 00:02:26.947 and it uses it like a bat uses sonar. 00:02:26.947 --> 00:02:28.548 Well a bat uses radar, but when it's underwater 00:02:28.548 --> 00:02:30.582 it's sonar, so this animal is using sonar 00:02:30.582 --> 00:02:33.528 to see its world in sound. 00:02:33.528 --> 00:02:35.041 Trying to understand how this works, 00:02:35.041 --> 00:02:36.790 you have to look at it as if you were looking 00:02:36.790 --> 00:02:39.009 at the amplifier speakers of a sound system. 00:02:39.009 --> 00:02:41.563 The small toothed whales are basically the "tweeters," 00:02:41.563 --> 00:02:43.079 and the sound is coming from that little 00:02:43.079 --> 00:02:45.280 nose that's moving back and forth 00:02:45.280 --> 00:02:46.845 and coming out of their forehead. 00:02:46.845 --> 00:02:48.288 But when you look at the big whales, 00:02:48.288 --> 00:02:49.778 they're kind of link the "woofer," 00:02:49.778 --> 00:02:52.167 the big speakers that you have in an amplifier system. 00:02:52.167 --> 00:02:55.154 And what's happening is their sound's coming out of the throat. 00:02:55.154 --> 00:02:57.336 So if you tried to make sound like a whale, 00:02:57.336 --> 00:02:58.491 you just make a sound right now, 00:02:58.491 --> 00:03:01.027 like go "ah." 00:03:01.027 --> 00:03:02.945 Okay, now put your hand on your throat, 00:03:02.945 --> 00:03:06.203 on your Adam's apple, you feel that vibration right there? 00:03:06.203 --> 00:03:08.003 That is lost energy for you 00:03:08.003 --> 00:03:10.400 because that's not how you're communicating to everybody. 00:03:10.400 --> 00:03:11.607 You're doing it out of the mouth. 00:03:11.607 --> 00:03:13.065 But if you open your mouth underwater, 00:03:13.065 --> 00:03:14.484 no one is going to hear you. 00:03:14.484 --> 00:03:17.810 You have to be able to take this energy and amplify it through the water, 00:03:17.810 --> 00:03:19.484 and that's what whales do. 00:03:19.484 --> 00:03:20.984 And when you hear their sound, 00:03:20.984 --> 00:03:22.126 [whale sounds] 00:03:22.126 --> 00:03:24.772 Hear that? It's kind of like when you squeak the air out of a balloon. 00:03:24.772 --> 00:03:26.951 So they get a lot of squeaky noises, 00:03:26.951 --> 00:03:28.401 but they also have this sound: 00:03:28.401 --> 00:03:30.716 [whale noises] 00:03:30.716 --> 00:03:32.771 It sounds like it's farting, doesn't it? 00:03:32.771 --> 00:03:36.037 It's like it's got this giant whoopie cushion in its throat. 00:03:36.037 --> 00:03:38.489 So, how do you know that's what a whale's doing? 00:03:38.489 --> 00:03:40.909 Well, we study whales that come to us from strandings. 00:03:40.909 --> 00:03:42.575 These are animals that die on the beach. 00:03:42.575 --> 00:03:44.736 Now the small whales, like dolphins and porpoises are easy, 00:03:44.736 --> 00:03:46.680 we can take them back to the lab. 00:03:46.680 --> 00:03:49.589 But the big whales, we've got to bring the lab to the whale. 00:03:49.589 --> 00:03:51.379 And this is what that would look like. 00:03:51.379 --> 00:03:54.074 So I'm the one in the middle with the red hat. 00:03:54.074 --> 00:03:55.590 I'm not a very tall person, 00:03:55.590 --> 00:03:57.733 so you can see how big this whale is compared to me. 00:03:57.733 --> 00:04:00.354 The whale is 65 feet long, and my scalpel 00:04:00.354 --> 00:04:02.301 is this little tool on the side here. 00:04:02.301 --> 00:04:03.798 It basically looks like a hockey stick 00:04:03.798 --> 00:04:05.699 with a blade on the end of it. 00:04:05.699 --> 00:04:08.534 And doing a dissection of a whale is a very difficult process. 00:04:08.534 --> 00:04:10.692 You literally have to get into your work. 00:04:10.692 --> 00:04:13.262 It's kind of like a giant bloody construction zone. 00:04:13.262 --> 00:04:14.582 You're wearing a hard hat, 00:04:14.582 --> 00:04:16.563 you're working with heavy machinery. 00:04:16.563 --> 00:04:17.677 In this case, by the way, 00:04:17.677 --> 00:04:21.219 that's just the voice box of a blue whale; just the voice box. 00:04:21.219 --> 00:04:23.388 And I'm only five feet tall, so you can see, 00:04:23.388 --> 00:04:24.864 it's already like twelve feet long there. 00:04:24.864 --> 00:04:25.991 How do we know what's going on? 00:04:25.991 --> 00:04:28.559 Well, we look at the voice box, or larynx, 00:04:28.559 --> 00:04:29.456 and we see inside. 00:04:29.456 --> 00:04:31.610 This is from a baby whale so it's much smaller. 00:04:31.610 --> 00:04:32.963 You see this little "u" shaped thing 00:04:32.963 --> 00:04:34.236 that I've outlined in blue; 00:04:34.236 --> 00:04:35.622 that's the part that's vibrating. 00:04:35.622 --> 00:04:37.400 That's kind of like our vocal folds. 00:04:37.400 --> 00:04:38.892 And when I put my hand in there, 00:04:38.892 --> 00:04:40.356 that's where that blue sleeve is, 00:04:40.356 --> 00:04:41.934 you can see there's a sack underneath it. 00:04:41.934 --> 00:04:43.303 That's the whoopie cushion. 00:04:43.303 --> 00:04:45.440 That's the air bubble or the balloon. 00:04:45.440 --> 00:04:46.728 So what these animals are doing, 00:04:46.728 --> 00:04:47.766 and you can see in this picture, 00:04:47.766 --> 00:04:49.555 there's this big black balloon in the throat, 00:04:49.555 --> 00:04:51.609 where the digestive track, which is in blue, 00:04:51.609 --> 00:04:54.115 meets the breathing track, which is in light blue, 00:04:54.115 --> 00:04:55.301 so you have light blue and dark blue, 00:04:55.301 --> 00:04:56.921 and right in the middle is that black sack. 00:04:56.921 --> 00:04:59.512 These animals are using that sack to make these sounds. 00:04:59.512 --> 00:05:02.045 And so they vibrate that and send it out. 00:05:02.045 --> 00:05:04.195 Small toothed whales also have air sacks, 00:05:04.195 --> 00:05:05.141 and they're all over their heads, 00:05:05.141 --> 00:05:06.668 so it's kind of like they're airheads. 00:05:06.668 --> 00:05:08.866 And they use this to capture as much air as they can, 00:05:08.866 --> 00:05:10.890 to take it down with them when they're diving, 00:05:10.890 --> 00:05:13.023 because when you dive, pressures increase, 00:05:13.023 --> 00:05:15.725 and that decreases the volume of air you have available. 00:05:15.725 --> 00:05:18.257 But more importantly, having that sack allows them to 00:05:18.257 --> 00:05:20.511 recycle the air that they're using 00:05:20.511 --> 00:05:21.923 because air is a precious commodity. 00:05:21.923 --> 00:05:23.513 You don't want to have to go back up to the surface 00:05:23.513 --> 00:05:24.808 to get more air. 00:05:24.808 --> 00:05:26.677 So when you make a sound underwater, 00:05:26.677 --> 00:05:27.756 if you're a whale, 00:05:27.756 --> 00:05:28.725 let's here you start making a sound. 00:05:28.725 --> 00:05:30.413 Go "ah." 00:05:30.413 --> 00:05:31.861 But whales keep their mouths closed, so go 00:05:31.861 --> 00:05:33.730 [mouth noises] 00:05:33.730 --> 00:05:34.953 You're all humming, right? 00:05:34.953 --> 00:05:35.947 But whales keep their nose closed, so go 00:05:35.947 --> 00:05:39.021 [mouth noises] 00:05:39.021 --> 00:05:41.851 What happened? You can't make the sound anymore 00:05:41.851 --> 00:05:44.497 once you close your nose because you've pressurized the system. 00:05:44.497 --> 00:05:46.084 So whales by having air sacks 00:05:46.084 --> 00:05:48.542 keep themselves from pressurizing the system 00:05:48.542 --> 00:05:50.693 which means the air continues to flow, 00:05:50.693 --> 00:05:52.461 and so if you had a bag on the end of your nose, 00:05:52.461 --> 00:05:55.037 you'd be able to make air continue to flow. 00:05:55.037 --> 00:05:56.453 So I hope you've enjoyed that. 00:05:56.453 --> 00:05:59.113 That's what a comparative anatomist does for their living. 00:05:59.113 --> 00:06:00.880 We study the structure of these animals. 00:06:00.880 --> 00:06:01.890 We try to mimic it. 00:06:01.890 --> 00:06:03.835 We apply it back to the human situation, 00:06:03.835 --> 00:06:06.895 maybe making new technologies for protective devices, 00:06:06.895 --> 00:06:09.152 or maybe even making new treatments for medicines 00:06:09.152 --> 00:06:12.024 for peoples' diseases who mimic these weird environments. 00:06:12.024 --> 00:06:14.248 So I hope you enjoyed that. Thank you.