1 00:00:06,142 --> 00:00:07,301 Hi, everybody! 2 00:00:07,325 --> 00:00:09,100 I am a comparative anatomist. 3 00:00:09,124 --> 00:00:12,584 A comparative anatomist is someone who studies the structure of the body 4 00:00:12,608 --> 00:00:13,997 of lots of different animals. 5 00:00:14,021 --> 00:00:15,910 And my favorite animals are whales. 6 00:00:15,934 --> 00:00:18,469 I like to study whales because they're so interesting. 7 00:00:18,493 --> 00:00:21,461 They've adapted to a unique environment of living in the water. 8 00:00:21,485 --> 00:00:24,779 And what I'm going to tell you about is how whales make sounds 9 00:00:24,803 --> 00:00:27,848 by basically farting with their face. 10 00:00:27,872 --> 00:00:30,743 You know that they do this farting thing with their blowhole; 11 00:00:30,767 --> 00:00:32,102 they blow out air like that, 12 00:00:32,126 --> 00:00:34,194 but they also use air in lots of other ways. 13 00:00:34,218 --> 00:00:37,138 They use it for sound production, which is what I'll focus on, 14 00:00:37,162 --> 00:00:39,370 but I also study other things they do with air, 15 00:00:39,394 --> 00:00:42,396 like keep it out of their bloodstream so they don't get bubbles, 16 00:00:42,420 --> 00:00:44,423 which is what happens to human scuba divers 17 00:00:44,447 --> 00:00:46,212 when they get decompression sickness. 18 00:00:46,236 --> 00:00:47,974 But I'd like to start with the story 19 00:00:47,998 --> 00:00:50,197 of how these animals make these farting noises, 20 00:00:50,221 --> 00:00:53,721 and that story begins with understanding how hard it is to look at whales, 21 00:00:53,745 --> 00:00:56,364 because they live underwater and they're really big, 22 00:00:56,388 --> 00:00:58,206 so they're hard animals to study. 23 00:00:58,230 --> 00:01:00,917 And in this picture -- you see that animal in the middle? 24 00:01:00,941 --> 00:01:03,827 That's a baby whale and it's already the size of a bus! 25 00:01:03,851 --> 00:01:06,549 When you look at whales, start with the top of their head 26 00:01:06,573 --> 00:01:08,859 because their nose is on the top of their head, 27 00:01:08,883 --> 00:01:10,419 kind of like a built-in snorkel. 28 00:01:10,443 --> 00:01:12,744 They breathe through that because they're mammals 29 00:01:12,768 --> 00:01:14,028 and mammals breathe air. 30 00:01:14,052 --> 00:01:15,869 Their nose can be opened and closed, 31 00:01:15,893 --> 00:01:17,672 as if you were to pinch it like this. 32 00:01:17,696 --> 00:01:20,902 You can see it's open in the bottom frame, where the red arrows are. 33 00:01:20,926 --> 00:01:22,982 But not all whales have two nostrils. 34 00:01:23,006 --> 00:01:25,823 Whales include the groups of dolphins and porpoises, 35 00:01:25,847 --> 00:01:27,975 and dolphins and porpoises, the small whales, 36 00:01:27,999 --> 00:01:30,333 have only one nostril on the top of their head, 37 00:01:30,357 --> 00:01:32,332 and they open and close that nostril 38 00:01:32,356 --> 00:01:35,609 by taking what is essentially an upper lip, like this, 39 00:01:35,633 --> 00:01:38,872 and turning it back over their nose, like this. 40 00:01:38,896 --> 00:01:41,054 That's how they open and close their nose. 41 00:01:41,078 --> 00:01:42,284 So when they make sounds, 42 00:01:42,308 --> 00:01:44,443 what they're basically doing is a raspberry, 43 00:01:44,467 --> 00:01:47,690 (Makes raspberry sound) which is kind of like a fart, right? 44 00:01:47,714 --> 00:01:49,874 Or up in New York, we call it a Bronx cheer. 45 00:01:49,898 --> 00:01:51,223 And the way they do that 46 00:01:51,247 --> 00:01:54,175 is by taking that big, fatty structure of a big fat lip, 47 00:01:54,199 --> 00:01:56,201 which, as you can see here in this picture, 48 00:01:56,225 --> 00:01:58,749 which is a cut through the middle of a dolphin's head, 49 00:01:58,773 --> 00:02:01,161 that big fat lip is that big yellow portion there, 50 00:02:01,185 --> 00:02:04,448 and they roll it back and forth over the top of their nose 51 00:02:04,472 --> 00:02:05,757 so that they vibrate it, 52 00:02:05,781 --> 00:02:08,126 kind of like when you let the air out of a balloon 53 00:02:08,150 --> 00:02:10,087 and it makes that weird vibration sound. 54 00:02:10,111 --> 00:02:12,855 So this is what it sounds like when they make their noise: 55 00:02:12,879 --> 00:02:13,899 (Vibration noise) 56 00:02:13,923 --> 00:02:16,371 Hear it? He'll do it again when he faces the camera. 57 00:02:16,395 --> 00:02:17,410 (Vibration noise) 58 00:02:17,434 --> 00:02:19,158 Sounds like it's farting underwater. 59 00:02:19,182 --> 00:02:22,276 What that dolphin is actually doing, though, is echolocation, 60 00:02:22,300 --> 00:02:24,389 which is making these series of pulses, 61 00:02:24,413 --> 00:02:26,702 and it uses it like a bat uses sonar. 62 00:02:26,726 --> 00:02:29,558 Well, a bat uses radar, but when it's underwater it's sonar, 63 00:02:29,582 --> 00:02:33,247 so this animal is using sonar to see its world in sound. 64 00:02:33,271 --> 00:02:36,086 Trying to understand how this works, you have to look at it 65 00:02:36,110 --> 00:02:39,284 as if you were looking at the amplifier speakers of a sound system. 66 00:02:39,308 --> 00:02:41,863 The small-toothed whales are basically the "tweeters," 67 00:02:41,887 --> 00:02:43,999 and the sound is coming from that little nose 68 00:02:44,023 --> 00:02:46,950 that's moving back and forth and coming out of their forehead. 69 00:02:46,974 --> 00:02:49,594 But the big whales are kind of like the "woofers," 70 00:02:49,618 --> 00:02:52,181 the big speakers that you have in an amplifier system. 71 00:02:52,205 --> 00:02:55,236 And what's happening is their sound is coming out of the throat. 72 00:02:55,260 --> 00:02:57,380 So if you tried to make sound like a whale -- 73 00:02:57,404 --> 00:03:00,785 make a sound right now, and go, "ahhhhhh." 74 00:03:00,809 --> 00:03:03,897 OK, now put your hand on your throat, on your Adam's apple. 75 00:03:03,921 --> 00:03:06,043 You feel that vibration right there? 76 00:03:06,067 --> 00:03:07,978 That is lost energy for you, 77 00:03:08,002 --> 00:03:10,439 because that's not how you communicate to everybody. 78 00:03:10,463 --> 00:03:11,916 You do it out of the mouth. 79 00:03:11,940 --> 00:03:14,757 But if you open your mouth underwater, no one will hear you. 80 00:03:14,781 --> 00:03:18,249 You have to be able to take this energy and amplify it through the water. 81 00:03:18,273 --> 00:03:19,460 That's what whales do. 82 00:03:19,484 --> 00:03:21,055 And when you hear their sound -- 83 00:03:21,079 --> 00:03:22,392 (Squeaking sound) 84 00:03:22,416 --> 00:03:25,202 it's kind of like when you squeak the air out of a balloon. 85 00:03:25,226 --> 00:03:27,106 So they get a lot of squeaky noises, 86 00:03:27,130 --> 00:03:28,606 but they also have this sound: 87 00:03:28,630 --> 00:03:30,543 (Vibrating sound) 88 00:03:30,567 --> 00:03:32,621 It sounds like it's farting, doesn't it? 89 00:03:32,645 --> 00:03:36,013 It's like it's got this giant whoopee cushion in its throat. 90 00:03:36,037 --> 00:03:38,375 So, how do you know that's what a whale is doing? 91 00:03:38,399 --> 00:03:40,947 Well, we study whales that come to us from strandings. 92 00:03:40,971 --> 00:03:42,895 These are animals that die on the beach. 93 00:03:42,919 --> 00:03:45,332 Small whales like dolphins and porpoises are easy; 94 00:03:45,356 --> 00:03:46,712 we can take them to the lab. 95 00:03:46,736 --> 00:03:49,649 But the big whales -- we've got to bring the lab to the whale. 96 00:03:49,673 --> 00:03:51,355 And this is what that looks like. 97 00:03:51,379 --> 00:03:54,114 I'm the one in the middle with the red hat. 98 00:03:54,138 --> 00:03:55,566 I'm not a very tall person, 99 00:03:55,590 --> 00:03:58,083 so you can see how big this whale was compared to me. 100 00:03:58,107 --> 00:03:59,362 The whale is 65 feet long. 101 00:03:59,386 --> 00:04:02,123 And my scalpel is this little tool on the side here. 102 00:04:02,147 --> 00:04:05,521 It basically looks like a hockey stick with a blade on the end of it. 103 00:04:05,545 --> 00:04:08,510 And doing a dissection of a whale is a very difficult process. 104 00:04:08,534 --> 00:04:10,493 You literally have to get into your work. 105 00:04:10,517 --> 00:04:13,238 It's kind of like a giant bloody construction zone. 106 00:04:13,262 --> 00:04:14,558 You're wearing a hard hat, 107 00:04:14,582 --> 00:04:16,539 you're working with heavy machinery. 108 00:04:16,563 --> 00:04:17,896 In this case, by the way, 109 00:04:17,920 --> 00:04:20,738 that's just the voice box of a blue whale. 110 00:04:20,762 --> 00:04:21,913 Just the voice box. 111 00:04:21,937 --> 00:04:24,865 I'm only five feet tall -- you can see it's like 12 feet long. 112 00:04:24,889 --> 00:04:26,373 How do we know what's going on? 113 00:04:26,397 --> 00:04:28,461 Well, we look at the voice box, or larynx, 114 00:04:28,485 --> 00:04:31,426 and we see -- this is from a baby whale so it's much smaller. 115 00:04:31,450 --> 00:04:34,124 You see this little u-shaped thing I've outlined in blue. 116 00:04:34,148 --> 00:04:35,729 That's the part that's vibrating. 117 00:04:35,753 --> 00:04:37,376 It's kind of like our vocal folds. 118 00:04:37,400 --> 00:04:40,004 When I put my hand in there, where that blue sleeve is, 119 00:04:40,028 --> 00:04:41,987 you can see there's a sack underneath it. 120 00:04:42,011 --> 00:04:43,313 That's the whoopee cushion. 121 00:04:43,337 --> 00:04:45,344 That's the air bubble or the balloon. 122 00:04:45,368 --> 00:04:47,008 So what these animals are doing -- 123 00:04:47,032 --> 00:04:50,001 and you can see, there's this big black balloon in the throat, 124 00:04:50,025 --> 00:04:52,096 where the digestive tract, which is in blue, 125 00:04:52,120 --> 00:04:54,927 meets the breathing tract, which is in light blue, 126 00:04:54,951 --> 00:04:56,957 and right in the middle is that black sack. 127 00:04:56,981 --> 00:04:59,569 These animals are using that sack to make these sounds. 128 00:04:59,593 --> 00:05:01,788 And so they vibrate that and send it out. 129 00:05:01,812 --> 00:05:05,181 Small-toothed whales also have air sacks; they're all over their heads, 130 00:05:05,205 --> 00:05:06,644 so it's like they're airheads. 131 00:05:06,668 --> 00:05:08,929 They use this to capture as much air as they can 132 00:05:08,953 --> 00:05:10,961 to take down with them when they're diving, 133 00:05:10,985 --> 00:05:13,021 because when you dive, pressures increase, 134 00:05:13,045 --> 00:05:15,761 and that decreases the volume of air you have available. 135 00:05:15,785 --> 00:05:16,937 But more importantly, 136 00:05:16,961 --> 00:05:20,257 having that sack allows them to recycle the air that they're using, 137 00:05:20,281 --> 00:05:22,008 because air is a precious commodity. 138 00:05:22,032 --> 00:05:25,050 You don't want to have to go back up to the surface to get more. 139 00:05:25,074 --> 00:05:27,768 So when you make a sound underwater, if you're a whale -- 140 00:05:27,792 --> 00:05:30,332 let's hear you start making a sound, go "ahhhh." 141 00:05:30,356 --> 00:05:32,816 But whales keep their mouths closed, so go "ahhhmm." 142 00:05:32,840 --> 00:05:33,895 (Audience makes noise) 143 00:05:33,919 --> 00:05:35,189 You're all humming, right? 144 00:05:35,213 --> 00:05:37,514 But whales keep their nose closed and go, "mmmm." 145 00:05:37,538 --> 00:05:38,688 (Makes noise) 146 00:05:38,863 --> 00:05:40,387 What happened? 147 00:05:40,411 --> 00:05:43,084 You can't make the sound anymore once you close your nose 148 00:05:43,108 --> 00:05:44,933 because you've pressurized the system. 149 00:05:44,957 --> 00:05:48,567 Whales, by having air sacks, keep themselves from pressurizing the system, 150 00:05:48,591 --> 00:05:50,669 which means the air continues to flow, 151 00:05:50,693 --> 00:05:52,971 and so if you had a bag on the end of your nose, 152 00:05:52,995 --> 00:05:55,003 you'd be able to make air continue to flow. 153 00:05:55,027 --> 00:05:56,603 So I hope you've enjoyed that. 154 00:05:56,627 --> 00:05:59,174 That's what a comparative anatomist does for a living. 155 00:05:59,198 --> 00:06:01,113 We study the structure of these animals. 156 00:06:01,137 --> 00:06:03,962 We try to mimic it; we apply it back to the human situation, 157 00:06:03,986 --> 00:06:06,977 maybe making new technologies for protective devices 158 00:06:07,001 --> 00:06:09,311 or maybe even making new treatments for medicines 159 00:06:09,335 --> 00:06:12,275 for people's diseases who mimic these weird environments. 160 00:06:12,299 --> 00:06:14,145 So I hope you enjoyed that. Thank you. 161 00:06:14,169 --> 00:06:15,319 (Applause)