WEBVTT 00:00:01.869 --> 00:00:03.836 It's 1878. 00:00:04.969 --> 00:00:08.247 Sir Francis Galton gives a remarkable talk. 00:00:09.318 --> 00:00:13.456 He's speaking to the anthropologic institute of Great Britain and Ireland. 00:00:14.170 --> 00:00:18.196 Known for his pioneering work in human intelligence, 00:00:18.220 --> 00:00:20.208 Galton is a brilliant polymath. 00:00:21.716 --> 00:00:23.270 He's an explorer, 00:00:23.294 --> 00:00:25.047 an anthropologist, 00:00:25.071 --> 00:00:26.601 a sociologist, 00:00:26.625 --> 00:00:28.194 a psychologist 00:00:28.218 --> 00:00:29.692 and a statistician. 00:00:31.387 --> 00:00:33.669 He's also a eugenist. 00:00:34.600 --> 00:00:35.846 In this talk, 00:00:36.807 --> 00:00:41.560 he presents a new technique by which he can combine photographs 00:00:41.584 --> 00:00:43.843 and produce composite portraits. 00:00:44.663 --> 00:00:49.677 This technique could be used to characterize different types of people. 00:00:50.702 --> 00:00:56.051 Galton thinks that if he combines photographs of violent criminals, 00:00:56.075 --> 00:00:59.201 he will discover the face of criminality. 00:01:00.253 --> 00:01:02.240 But to his surprise, 00:01:02.264 --> 00:01:05.128 the composite portrait that he produces 00:01:05.951 --> 00:01:07.207 is beautiful. NOTE Paragraph 00:01:10.026 --> 00:01:13.054 Galton's surprising finding raises deep questions: 00:01:13.515 --> 00:01:15.100 What is beauty? 00:01:16.070 --> 00:01:22.889 Why do certain configurations of line and color and form excite us so? 00:01:24.372 --> 00:01:25.900 For most of human history, 00:01:25.924 --> 00:01:31.479 these questions have been approached using logic and speculation. 00:01:32.115 --> 00:01:33.632 But in the last few decades, 00:01:33.656 --> 00:01:36.534 scientists have addressed the question of beauty 00:01:36.558 --> 00:01:41.627 using ideas from evolutionary psychology and tools of neuroscience. 00:01:42.502 --> 00:01:46.365 We're beginning to glimpse the why and the how of beauty, 00:01:46.945 --> 00:01:50.269 at least in terms of what it means for the human face and form. 00:01:51.201 --> 00:01:52.757 And in the process, 00:01:52.781 --> 00:01:55.133 we're stumbling upon some surprises. NOTE Paragraph 00:01:56.160 --> 00:01:58.968 When it comes to seeing beauty in each other, 00:01:59.749 --> 00:02:04.104 while this decision is certainly subjective for the individual, 00:02:04.128 --> 00:02:08.311 it's sculpted by factors that contribute to the survival of the group. 00:02:08.810 --> 00:02:11.458 Many experiments have shown 00:02:11.482 --> 00:02:15.483 that a few basic parameters contribute to what makes a face attractive. 00:02:16.315 --> 00:02:21.991 These include averaging, symmetry and the effects of hormones. 00:02:22.015 --> 00:02:24.425 Let's take each one of these in turn. NOTE Paragraph 00:02:26.531 --> 00:02:28.005 Galton's finding 00:02:28.029 --> 00:02:33.312 that composite or average faces are typically more attractive 00:02:33.336 --> 00:02:36.893 than each individual face that contributes to the average 00:02:36.917 --> 00:02:38.846 has been replicated many times. 00:02:39.933 --> 00:02:44.122 This laboratory finding fits with many people's intuitions. 00:02:44.754 --> 00:02:48.965 Average faces represent the central tendencies of a group. 00:02:49.724 --> 00:02:54.043 People with mixed features represent different populations, 00:02:54.067 --> 00:02:57.415 and presumably harbor greater genetic diversity 00:02:57.439 --> 00:02:59.637 and adaptability to the environment. 00:03:00.337 --> 00:03:04.741 Many people find mixed-race individuals attractive, 00:03:04.765 --> 00:03:06.939 and inbred families less so. NOTE Paragraph 00:03:08.627 --> 00:03:12.810 The second factor that contributes to beauty is symmetry. 00:03:13.474 --> 00:03:17.800 People generally find symmetric faces more attractive than asymmetric ones. 00:03:18.758 --> 00:03:24.010 Developmental abnormalities are often associated with asymmetries, 00:03:24.034 --> 00:03:27.299 and in plants, animals and humans, 00:03:27.323 --> 00:03:30.629 asymmetries often arise from parasitic infections. 00:03:31.373 --> 00:03:33.591 Symmetry, it turns out, 00:03:33.615 --> 00:03:37.118 is also an indicator of health. 00:03:38.469 --> 00:03:40.063 In the 1930s, 00:03:40.779 --> 00:03:43.679 a man named Maksymilian Faktorowicz 00:03:43.703 --> 00:03:46.880 recognized the importance of symmetry for beauty 00:03:46.904 --> 00:03:49.059 when he designed the beauty micrometer. 00:03:50.297 --> 00:03:51.448 With this device, 00:03:51.472 --> 00:03:54.527 he could measure minor asymmetric flaws 00:03:54.551 --> 00:03:59.100 which he could then make up for with products he sold from his company, 00:03:59.124 --> 00:04:02.948 named brilliantly after himself, Max Factor, 00:04:02.972 --> 00:04:05.983 which, as you know, is one of the world's most famous brands 00:04:06.007 --> 00:04:07.175 for "make up." NOTE Paragraph 00:04:08.515 --> 00:04:12.473 The third factor that contributes to facial attractiveness 00:04:12.497 --> 00:04:14.210 is the effect of hormones. 00:04:15.533 --> 00:04:19.587 And here, I need to apologize for confining my comments 00:04:20.282 --> 00:04:21.849 to heterosexual norms. 00:04:23.618 --> 00:04:28.088 But estrogen and testosterone play important roles 00:04:28.112 --> 00:04:30.710 in shaping features that we find attractive. 00:04:31.643 --> 00:04:35.500 Estrogen produces features that signal fertility. 00:04:36.334 --> 00:04:39.284 Men typically find women attractive 00:04:39.308 --> 00:04:43.609 who have elements of both youth and maturity. 00:04:44.183 --> 00:04:48.156 A face that's too baby-like might mean that the girl is not yet fertile, 00:04:49.119 --> 00:04:51.092 so men find women attractive 00:04:51.116 --> 00:04:55.352 who have large eyes, full lips and narrow chins 00:04:55.376 --> 00:04:56.885 as indicators of youth, 00:04:57.700 --> 00:05:01.083 and high cheekbones as an indicator of maturity. 00:05:02.564 --> 00:05:07.847 Testosterone produces features that we regard as typically masculine. 00:05:08.777 --> 00:05:10.797 These include heavier brows, 00:05:10.821 --> 00:05:12.126 thinner cheeks 00:05:12.150 --> 00:05:14.402 and bigger, squared-off jaws. 00:05:14.426 --> 00:05:16.216 But here's a fascinating irony. 00:05:17.695 --> 00:05:18.846 In many species, 00:05:18.870 --> 00:05:20.251 if anything, 00:05:20.275 --> 00:05:23.967 testosterone suppresses the immune system. 00:05:25.002 --> 00:05:29.176 So the idea that testosterone-infused features are a fitness indicator 00:05:29.200 --> 00:05:31.425 doesn't really make a whole lot of sense. 00:05:32.183 --> 00:05:34.682 Here, the logic is turned on its head. 00:05:35.658 --> 00:05:37.807 Instead of a fitness indicator, 00:05:37.831 --> 00:05:41.238 scientists invoke a handicap principle. 00:05:42.789 --> 00:05:46.321 The most commonly cited example of a handicap 00:05:46.345 --> 00:05:47.836 is the peacock's tail. 00:05:48.542 --> 00:05:52.938 This beautiful but cumbersome tail doesn't exactly help the peacock 00:05:52.962 --> 00:05:54.224 avoid predators 00:05:54.910 --> 00:05:56.367 and approach peahens. 00:05:57.188 --> 00:06:00.640 Why should such an extravagant appendage evolve? 00:06:01.947 --> 00:06:03.542 Even Charles Darwin, 00:06:04.408 --> 00:06:07.807 in an 1860 letter to Asa Gray wrote 00:06:07.831 --> 00:06:11.603 that the sight of the peacock's tail made him physically ill. 00:06:12.144 --> 00:06:15.042 He couldn't explain it with his theory of natural selection, 00:06:15.066 --> 00:06:16.965 and out of this frustration, 00:06:16.989 --> 00:06:20.173 he developed the theory of sexual selection. NOTE Paragraph 00:06:21.501 --> 00:06:22.651 On this account, 00:06:22.675 --> 00:06:27.058 the display of the peacock's tail is about sexual enticement, 00:06:27.082 --> 00:06:33.304 and this enticement means it's more likely the peacock will mate 00:06:33.328 --> 00:06:34.662 and have offspring. 00:06:35.818 --> 00:06:38.807 Now, the modern twist on this display argument 00:06:39.472 --> 00:06:44.442 is that the peacock is also advertising its health to the peahen. 00:06:46.001 --> 00:06:51.128 Only especially fit organisms can afford to divert resources 00:06:51.152 --> 00:06:53.850 to maintaining such an extravagant appendage. 00:06:54.592 --> 00:06:59.485 Only especially fit men can afford the price that testosterone levies 00:06:59.509 --> 00:07:00.778 on their immune system. 00:07:01.560 --> 00:07:04.218 And by analogy, think of the fact 00:07:04.242 --> 00:07:11.207 that only very rich men can afford to pay more than $10,000 for a watch 00:07:11.231 --> 00:07:13.481 as a display of their financial fitness. NOTE Paragraph 00:07:15.113 --> 00:07:17.915 Now, many people hear these kinds of evolutionary claims 00:07:17.939 --> 00:07:23.669 and think they mean that we somehow are unconsciously seeking mates 00:07:23.693 --> 00:07:25.608 who are healthy. 00:07:25.632 --> 00:07:28.575 And I think this idea is probably not right. 00:07:30.269 --> 00:07:35.131 Teenagers and young adults are not exactly known for making decisions 00:07:35.155 --> 00:07:37.343 that are predicated on health concerns. 00:07:38.544 --> 00:07:40.145 But they don't have to be, 00:07:40.169 --> 00:07:41.652 and let me explain why. NOTE Paragraph 00:07:43.151 --> 00:07:44.502 Imagine a population 00:07:45.208 --> 00:07:49.386 in which people have three different kinds of preferences: 00:07:49.410 --> 00:07:52.735 for green, for orange and for red. 00:07:53.922 --> 00:07:55.113 From their point of view, 00:07:55.137 --> 00:07:57.500 these preferences have nothing to do with health; 00:07:57.524 --> 00:07:59.016 they just like what they like. 00:08:00.128 --> 00:08:04.169 But if it were also the case that these preferences are associated 00:08:04.193 --> 00:08:07.191 with the different likelihood of producing offspring -- 00:08:07.215 --> 00:08:10.077 let's say in a ratio of 3:2:1 -- 00:08:11.060 --> 00:08:12.504 then in the first generation, 00:08:12.528 --> 00:08:15.800 there would be 3 greens to 2 oranges to 1 red, 00:08:15.824 --> 00:08:18.010 and in each subsequent generation, 00:08:18.034 --> 00:08:20.740 the proportion of greens increase, 00:08:22.067 --> 00:08:23.778 so that in 10 generations, 00:08:23.802 --> 00:08:27.575 98 percent of this population has a green preference. 00:08:27.963 --> 00:08:31.084 Now, a scientist coming in and sampling this population 00:08:31.108 --> 00:08:34.757 discovers that green preferences are universal. 00:08:35.606 --> 00:08:39.478 So the point about this little abstract example 00:08:39.502 --> 00:08:44.162 is that while preferences for specific physical features 00:08:44.186 --> 00:08:46.749 can be arbitrary for the individual, 00:08:48.090 --> 00:08:49.860 if those features are heritable 00:08:53.232 --> 00:08:57.391 and they are associated with a reproductive advantage, 00:08:57.415 --> 00:08:58.629 over time, 00:08:58.653 --> 00:09:00.580 they become universal for the group. NOTE Paragraph 00:09:03.172 --> 00:09:08.373 So what happens in the brain when we see beautiful people? 00:09:10.520 --> 00:09:14.548 Attractive faces activate parts of our visual cortex 00:09:14.572 --> 00:09:16.517 in the back of the brain, 00:09:16.541 --> 00:09:18.483 an area called the fusiform gyrus, 00:09:18.507 --> 00:09:21.309 that is especially tuned to processing faces, 00:09:21.333 --> 00:09:25.347 and an adjacent area called the lateral occipital complex, 00:09:25.371 --> 00:09:28.127 that is especially attuned to processing objects. 00:09:28.700 --> 00:09:30.096 In addition, 00:09:30.120 --> 00:09:35.198 attractive faces activate parts of our reward and pleasure centers 00:09:35.222 --> 00:09:37.487 in the front and deep in the brain, 00:09:38.179 --> 00:09:41.303 and these include areas that have complicated names, 00:09:41.327 --> 00:09:43.191 like the ventral striatum, 00:09:43.215 --> 00:09:45.134 the orbitofrontal cortex 00:09:45.158 --> 00:09:47.752 and the ventromedial prefrontal cortex. 00:09:48.732 --> 00:09:52.716 Our visual brain that is tuned to processing faces 00:09:52.740 --> 00:09:55.377 interacts with our pleasure centers 00:09:55.401 --> 00:09:57.848 to underpin the experience of beauty. NOTE Paragraph 00:09:59.719 --> 00:10:03.811 Amazingly, while we all engage with beauty, 00:10:03.835 --> 00:10:05.432 without our knowledge, 00:10:05.456 --> 00:10:07.214 beauty also engages us. 00:10:08.478 --> 00:10:10.977 Our brains respond to attractive faces 00:10:11.001 --> 00:10:13.355 even when we're not thinking about beauty. 00:10:14.637 --> 00:10:18.926 We conducted an experiment in which people saw a series of faces, 00:10:18.950 --> 00:10:20.653 and in one condition, 00:10:20.677 --> 00:10:26.253 they had to decide if a pair of faces were the same or a different person. 00:10:27.907 --> 00:10:30.400 Even in this condition, 00:10:30.424 --> 00:10:36.566 attractive faces drove neural activity robustly in their visual cortex, 00:10:36.590 --> 00:10:40.103 despite the fact that they were thinking about a person's identity 00:10:40.127 --> 00:10:41.428 and not their beauty. 00:10:43.127 --> 00:10:47.438 Another group similarly found automatic responses to beauty 00:10:47.462 --> 00:10:49.625 within our pleasure centers. 00:10:50.551 --> 00:10:53.340 Taken together, these studies suggest 00:10:54.033 --> 00:10:58.544 that our brain automatically responds to beauty 00:10:58.568 --> 00:11:00.583 by linking vision and pleasure. 00:11:01.854 --> 00:11:04.234 These beauty detectors, it seems, 00:11:04.258 --> 00:11:06.096 ping every time we see beauty, 00:11:06.120 --> 00:11:08.814 regardless of whatever else we might be thinking. NOTE Paragraph 00:11:11.022 --> 00:11:16.511 We also have a "beauty is good" stereotype embedded in the brain. 00:11:17.712 --> 00:11:19.939 Within the orbitofrontal cortex, 00:11:19.963 --> 00:11:21.738 there's overlapping neural activity 00:11:21.762 --> 00:11:25.546 in response to beauty and to goodness, 00:11:27.185 --> 00:11:30.707 and this happens even when people aren't explicitly thinking 00:11:30.731 --> 00:11:32.334 about beauty or goodness. 00:11:33.906 --> 00:11:37.865 Our brains seem to reflexively associate beauty and good. 00:11:38.690 --> 00:11:42.668 And this reflexive association may be the biologic trigger 00:11:42.692 --> 00:11:45.374 for the many social effects of beauty. 00:11:46.057 --> 00:11:50.451 Attractive people receive all kinds of advantages in life. 00:11:51.556 --> 00:11:54.310 They're regarded as more intelligent, 00:11:54.334 --> 00:11:55.937 more trustworthy, 00:11:55.961 --> 00:11:59.506 they're given higher pay and lesser punishments, 00:11:59.530 --> 00:12:02.252 even when such judgments are not warranted. 00:12:03.572 --> 00:12:06.912 These kinds of observations reveal beauty's ugly side. 00:12:07.796 --> 00:12:09.869 In my lab, we recently found 00:12:09.893 --> 00:12:14.815 that people with minor facial anomalies and disfigurements 00:12:14.839 --> 00:12:18.623 are regarded as less good, less kind, 00:12:18.647 --> 00:12:23.078 less intelligent, less competent and less hardworking. 00:12:23.854 --> 00:12:29.138 Unfortunately, we also have a "disfigured is bad" stereotype. 00:12:30.398 --> 00:12:37.056 This stereotype is probably exploited and magnified 00:12:37.080 --> 00:12:39.493 by images in popular media, 00:12:39.517 --> 00:12:43.413 in which facial disfigurement is often used as a shorthand 00:12:43.437 --> 00:12:46.095 to depict someone of villainous character. 00:12:47.378 --> 00:12:50.832 We need to understand these kinds of implicit biases 00:12:50.856 --> 00:12:52.593 if we are to overcome them, 00:12:52.617 --> 00:12:56.298 and aim for a society in which we treat people fairly, 00:12:56.322 --> 00:13:00.737 based on their behavior and not on the happenstance of their looks. NOTE Paragraph 00:13:04.758 --> 00:13:08.003 Let me leave you with one final thought. 00:13:09.044 --> 00:13:11.092 Beauty is a work in progress. 00:13:12.527 --> 00:13:15.734 The so-called universal attributes of beauty 00:13:15.758 --> 00:13:21.246 were selected for during the almost two million years of the Pleistocene. 00:13:21.944 --> 00:13:26.836 Life was nasty, brutish and a very long time ago. 00:13:28.014 --> 00:13:33.338 The selection criteria for reproductive success from that time 00:13:33.362 --> 00:13:35.227 doesn't really apply today. 00:13:35.966 --> 00:13:37.456 For example, 00:13:37.480 --> 00:13:41.547 death by parasite is not one of the top ways that people die, 00:13:41.571 --> 00:13:44.462 at least not in the technologically developed world. 00:13:45.997 --> 00:13:48.357 From antibiotics to surgery, 00:13:48.381 --> 00:13:51.873 birth control to in vitro fertilization, 00:13:51.897 --> 00:13:55.287 the filters for reproductive success are being relaxed. 00:13:55.956 --> 00:13:58.611 And under these relaxed conditions, 00:13:58.635 --> 00:14:02.869 preference and trait combinations are free to drift 00:14:02.893 --> 00:14:04.662 and become more variable. 00:14:05.416 --> 00:14:09.602 Even as we are profoundly affecting our environment, 00:14:10.985 --> 00:14:14.298 modern medicine and technological innovation 00:14:14.322 --> 00:14:16.075 is profoundly affecting 00:14:16.099 --> 00:14:19.821 the very essence of what it means to look beautiful. 00:14:21.197 --> 00:14:23.747 The universal nature of beauty is changing 00:14:23.771 --> 00:14:26.692 even as we're changing the universe. NOTE Paragraph 00:14:28.863 --> 00:14:30.048 Thank you. NOTE Paragraph 00:14:30.072 --> 00:14:33.658 (Applause)