WEBVTT 00:00:07.015 --> 00:00:09.485 When you think of natural history museums, 00:00:09.485 --> 00:00:14.116 you probably picture exhibits filled with ancient lifeless things, 00:00:14.116 --> 00:00:15.435 like dinosaurs 00:00:15.435 --> 00:00:16.463 meteroites, 00:00:16.463 --> 00:00:17.867 and gemstones. 00:00:17.867 --> 00:00:20.695 But behind that educational exterior, 00:00:20.695 --> 00:00:25.032 which only includes about 1% of a museum's collection, 00:00:25.032 --> 00:00:29.558 there are hidden laboratories where scientific breakthroughs are made. 00:00:29.558 --> 00:00:31.196 Beyond the unmarked doors, 00:00:31.196 --> 00:00:34.087 and on the floors the elevators won't take you to, 00:00:34.087 --> 00:00:37.488 you'd find windows into amazing worlds. 00:00:37.488 --> 00:00:42.017 This maze of halls and laboratories is a scientific sanctuary 00:00:42.017 --> 00:00:45.744 that houses a seemingly endless variety of specimens. 00:00:45.744 --> 00:00:49.507 Here, researchers work to unravel mysteries of evolution, 00:00:49.507 --> 00:00:51.261 cosmic origins, 00:00:51.261 --> 00:00:53.579 and the history of our planet. 00:00:53.579 --> 00:00:57.013 One museum alone may have millions of specimens. 00:00:57.013 --> 00:01:00.103 The American Museum of Natural History in New York City 00:01:00.103 --> 00:01:04.079 has over 32,000,000 in its collection. 00:01:04.079 --> 00:01:06.164 Let's take a look at just one of them. 00:01:06.164 --> 00:01:09.478 Scientists have logged exactly where and when it was found 00:01:09.478 --> 00:01:14.035 and used various dating techniques to pinpoint when it originated. 00:01:14.035 --> 00:01:17.307 Repeat that a million times over, and these plants, 00:01:17.307 --> 00:01:18.371 animals, 00:01:18.371 --> 00:01:19.228 minerals, 00:01:19.228 --> 00:01:20.106 fossils, 00:01:20.106 --> 00:01:25.239 and artifacts present windows into times and places around the world 00:01:25.239 --> 00:01:28.066 and across billions of years of history. 00:01:28.066 --> 00:01:29.872 When a research problem emerges, 00:01:29.872 --> 00:01:34.880 scientists peer through these windows and test hypotheses about the past. 00:01:34.880 --> 00:01:39.702 For example, in the 1950s, populations of predatory birds, 00:01:39.702 --> 00:01:41.331 like peregrine falcons, 00:01:41.331 --> 00:01:42.393 owls, 00:01:42.393 --> 00:01:45.014 and eagles started to mysteriously crash, 00:01:45.014 --> 00:01:48.668 to the point where a number of species, including the bald eagle, 00:01:48.668 --> 00:01:50.929 were declared endangered. 00:01:50.929 --> 00:01:54.553 Fortunately, scientists in The Field Museum in Chicago 00:01:54.553 --> 00:01:58.283 had been collecting the eggs of these predatory birds for decades. 00:01:58.283 --> 00:02:01.811 They discovered that the egg shells used to be thicker 00:02:01.811 --> 00:02:04.059 and had started to thin around the time 00:02:04.059 --> 00:02:09.616 when an insecticide called DDT started being sprayed on crops. 00:02:09.616 --> 00:02:12.436 DDT worked very well to kill insects, 00:02:12.436 --> 00:02:16.239 but when birds came and ate those heaps of dead bugs, 00:02:16.239 --> 00:02:19.372 the DDT accumulated in their bodies. 00:02:19.372 --> 00:02:21.401 It worked its way up the food chain 00:02:21.401 --> 00:02:26.473 and was absorbed by apex predator birds in such high concentrations 00:02:26.473 --> 00:02:28.299 that it thinned their eggs 00:02:28.299 --> 00:02:32.086 so that they couldn't support the nesting bird's weight. 00:02:32.086 --> 00:02:33.669 There were omelettes everywhere 00:02:33.669 --> 00:02:36.103 until scientists from The Field Museum in Chicago, 00:02:36.103 --> 00:02:37.642 and other institutions, 00:02:37.642 --> 00:02:40.493 helped solve the mystery and save the day. 00:02:40.493 --> 00:02:42.778 America thanks you, Field Museum. 00:02:42.778 --> 00:02:45.341 Natural history museums windows into the past 00:02:45.341 --> 00:02:48.326 have solved many other scientific mysteries. 00:02:48.326 --> 00:02:50.706 Museum scientists have used their collections 00:02:50.706 --> 00:02:53.077 to sequence the Neanderthal genome, 00:02:53.077 --> 00:02:56.129 discover genes that gave mammoths red fur, 00:02:56.129 --> 00:03:01.176 and even pinpoint where ancient giant sharks gave birth. 00:03:01.176 --> 00:03:04.476 There are about 900 natural history museums in the world, 00:03:04.476 --> 00:03:07.306 and every year they make new discoveries and insights 00:03:07.306 --> 00:03:10.934 into the Earth's past, present and future. 00:03:10.934 --> 00:03:14.208 Museum collections even help us understand how modern threats, 00:03:14.208 --> 00:03:16.172 such as global climate change, 00:03:16.172 --> 00:03:17.861 are impacting our world. 00:03:17.861 --> 00:03:20.404 For instance, naturalists have been collecting samples 00:03:20.404 --> 00:03:24.029 for over 100 years from Walden Pond, 00:03:24.029 --> 00:03:27.139 famously immortalized by Henry David Thoreau. 00:03:27.139 --> 00:03:30.426 Thanks to those naturalists, who count Thoreau among their number, 00:03:30.426 --> 00:03:32.735 we know that the plants around Walden Pond 00:03:32.735 --> 00:03:38.132 are blooming over three weeks earlier than they did 150 years ago. 00:03:38.132 --> 00:03:40.566 Because these changes have taken place gradually, 00:03:40.566 --> 00:03:44.710 one person may not have noticed them over the span of a few decades, 00:03:44.710 --> 00:03:46.635 but thanks to museum collections, 00:03:46.635 --> 00:03:51.535 we have an uninterrupted record showing how our world is changing. 00:03:51.535 --> 00:03:54.375 So the next time you're exploring a natural history museum, 00:03:54.375 --> 00:03:57.361 remember that what you're seeing is just one gem 00:03:57.361 --> 00:04:00.716 of a colossal scientific treasure trove. 00:04:00.716 --> 00:04:05.448 Behind those walls and under your feet are windows into forgotten worlds. 00:04:05.448 --> 00:04:06.609 And who knows? 00:04:06.609 --> 00:04:11.697 One day some future scientist may peer through one and see you.