0:00:00.880,0:00:02.880 So this is a story 0:00:02.904,0:00:05.269 about how we know what we know. 0:00:05.690,0:00:08.587 It's a story about this woman, 0:00:08.611,0:00:10.547 Natalia Rybczynski. 0:00:10.912,0:00:12.960 She's a paleobiologist, 0:00:12.984,0:00:16.868 which means she specializes[br]in digging up really old dead stuff. 0:00:16.892,0:00:19.750 (Audio) Natalia Rybczynski: Yeah,[br]I had someone who called me 0:00:19.774,0:00:20.925 Dr. Dead Things. 0:00:20.949,0:00:23.576 Latif Nasser: And I think she's[br]particularly interesting 0:00:23.600,0:00:25.513 because of where she digs that stuff up, 0:00:25.537,0:00:29.600 way above the Arctic Circle[br]in the remote Canadian tundra. 0:00:29.901,0:00:32.956 Now, one summer day in 2006, 0:00:32.980,0:00:36.171 she was at a dig site called[br]the Fyles Leaf Bed, 0:00:36.195,0:00:40.773 which is less than 10 degrees latitude[br]away from the magnetic north pole. 0:00:40.797,0:00:43.798 (Audio) NR: Really, like, it's not going[br]to sound very exciting, 0:00:43.822,0:00:47.578 because it was a day of walking[br]with your backpack and your GPS 0:00:47.602,0:00:51.680 and notebook and just picking up[br]anything that might be a fossil. 0:00:51.704,0:00:54.379 LN: And at some point,[br]she noticed something. 0:00:54.403,0:00:56.570 (Audio) NR: Rusty, kind of rust-colored, 0:00:56.594,0:00:58.529 about the size of the palm of my hand. 0:00:58.553,0:01:00.847 It was just lying on the surface. 0:01:00.871,0:01:04.323 LN: And at first she thought[br]it was just a splinter of wood, 0:01:04.347,0:01:06.640 because that's the sort of thing[br]people had found 0:01:06.664,0:01:10.083 at the Fyles Leaf Bed before,[br]prehistoric plant parts. 0:01:10.107,0:01:12.575 But that night, back at camp... 0:01:12.940,0:01:14.901 (Audio) NR: When I get out the hand lens, 0:01:14.925,0:01:17.314 I'm looking a little bit[br]more closely and realizing 0:01:17.338,0:01:19.718 it doesn't quite look like[br]this has tree rings. 0:01:19.742,0:01:21.306 Maybe it's a preservation thing, 0:01:21.330,0:01:24.829 but it looks really like bone. 0:01:24.853,0:01:27.742 LN: Huh. So over the next four years, 0:01:27.766,0:01:30.822 she went to that spot over and over 0:01:30.846,0:01:36.260 and eventually collected 30 fragments[br]of that exact same bone, 0:01:36.284,0:01:38.204 most of them really tiny. 0:01:38.522,0:01:42.958 (Audio) NR: It's not a whole lot.[br]It fits in a small Ziploc bag. 0:01:42.982,0:01:46.339 LN: And she tried to piece them together[br]like a jigsaw puzzle, 0:01:46.942,0:01:48.386 but it was challenging. 0:01:48.410,0:01:51.561 (Audio) NR: Because it's broken up[br]into so many little tiny pieces, 0:01:51.585,0:01:53.480 I'm trying to use sand and putty, 0:01:53.504,0:01:55.512 and it's not looking good, 0:01:55.536,0:02:00.703 so finally we had a 3D surface scanner. 0:02:00.727,0:02:02.316 LN: Ooh![br]NR: Yeah, right? 0:02:02.340,0:02:03.780 (Laughter) 0:02:03.804,0:02:06.547 LN: It turns out it was way easier[br]to do it virtually. 0:02:06.571,0:02:09.341 (Audio) NR: It's kind of magical[br]when it all fits together. 0:02:09.365,0:02:11.564 LN: How certain were you[br]that you had it right, 0:02:11.588,0:02:13.733 that you had put it together[br]in the right way? 0:02:13.757,0:02:16.670 Was there a potential that you[br]put it together a different way 0:02:16.694,0:02:18.695 and you had, like,[br]a parakeet or something? 0:02:18.719,0:02:23.958 (Audio) NR: (Laughs) Umm, no.[br]No, we got this. 0:02:23.982,0:02:28.083 LN: What she had, she discovered,[br]was a tibia, a leg bone, 0:02:28.107,0:02:32.107 and specifically one that belonged[br]to a cloven-hoofed mammal, 0:02:32.131,0:02:34.980 so something like a cow or a sheep. 0:02:35.004,0:02:37.464 But it couldn't have been either of those. 0:02:37.488,0:02:39.798 It was just too big. 0:02:39.822,0:02:43.885 (Audio) NR: The size of this thing,[br]it was huge. It's a really big animal. 0:02:43.909,0:02:46.950 LN: So what animal could it be? 0:02:47.291,0:02:49.871 Having hit a wall, she showed[br]one of the fragments 0:02:49.895,0:02:52.146 to some colleagues of hers in Colorado, 0:02:52.170,0:02:54.220 and they had an idea. 0:02:54.244,0:02:59.291 (Audio) NR: We took a saw,[br]and we nicked just the edge of it, 0:02:59.315,0:03:06.008 and there was this really interesting[br]smell that comes from it. 0:03:06.521,0:03:09.284 LN: It smelled kind of like singed flesh. 0:03:09.308,0:03:13.388 It was a smell that Natalia recognized[br]from cutting up skulls 0:03:13.412,0:03:16.974 in her gross anatomy lab: collagen. 0:03:16.998,0:03:19.777 Collagen is what gives[br]structure to our bones. 0:03:19.801,0:03:21.959 And usually, after so many years, 0:03:21.983,0:03:23.134 it breaks down. 0:03:23.158,0:03:27.506 But in this case, the Arctic had acted[br]like a natural freezer and preserved it. 0:03:28.205,0:03:29.555 Then a year or two later, 0:03:29.579,0:03:32.848 Natalia was at a conference in Bristol, 0:03:32.872,0:03:35.451 and she saw that a colleague of hers[br]named Mike Buckley 0:03:35.475,0:03:41.030 was demoing this new process[br]that he called collagen fingerprinting. 0:03:41.356,0:03:45.062 It turns out that different species[br]have slightly different structures 0:03:45.086,0:03:48.943 of collagen, so if you get a collagen[br]profile of an unknown bone, 0:03:48.967,0:03:51.286 you can compare it[br]to those of known species, 0:03:51.310,0:03:54.187 and who knows, maybe you get a match. 0:03:54.546,0:03:57.825 So she shipped him one of the fragments, 0:03:57.849,0:03:59.143 FedEx. 0:03:59.167,0:04:02.977 (Audio) NR: Yeah, you want to track it.[br]It's kind of important. 0:04:03.001,0:04:04.254 (Laughter) 0:04:04.278,0:04:06.738 LN: And he processed it, and compared it 0:04:06.762,0:04:10.127 to 37 known and modern day mammal species. 0:04:10.674,0:04:12.323 And he found a match. 0:04:12.347,0:04:17.436 It turns out that[br]the 3.5 million-year-old bone 0:04:17.460,0:04:21.705 that Natalia had dug[br]out of the High Arctic 0:04:21.729,0:04:24.007 belonged to... 0:04:24.031,0:04:25.348 a camel. 0:04:25.372,0:04:27.103 (Laughter) 0:04:27.127,0:04:31.425 (Audio) NR: And I'm thinking, what?[br]That's amazing, if it's true. 0:04:31.449,0:04:33.501 LN: So they tested[br]a bunch of the fragments, 0:04:33.525,0:04:35.769 and they got the same result for each one. 0:04:36.198,0:04:41.197 However, based on the size[br]of the bone that they found 0:04:41.221,0:04:44.364 was such that it meant that this camel 0:04:44.388,0:04:48.003 was 30 percent larger[br]than modern day camels. 0:04:48.027,0:04:51.218 So this camel would have been[br]about nine feet tall, 0:04:51.242,0:04:53.444 weighed around a ton. 0:04:53.468,0:04:54.482 Yeah. 0:04:54.506,0:04:58.230 Natalia had found a giant Arctic camel. 0:04:58.254,0:05:00.396 (Laughter) 0:05:02.396,0:05:04.714 Now, when you hear the word camel, 0:05:04.738,0:05:09.094 what may come to mind is one of these, 0:05:09.507,0:05:12.871 the Bactrian camel[br]of East and Central Asia. 0:05:12.895,0:05:16.380 But chances are the postcard image[br]you have in your brain 0:05:16.404,0:05:19.959 is one of these, the dromedary, 0:05:19.983,0:05:22.411 quintessential desert creature -- 0:05:22.435,0:05:26.754 hangs out in sandy, hot places[br]like the Middle East and the Sahara, 0:05:26.778,0:05:29.212 has a big old hump on its back[br]for storing water 0:05:29.236,0:05:30.799 for those long desert treks, 0:05:30.823,0:05:34.592 has big, broad feet to help it[br]tromp over sand dunes. 0:05:34.918,0:05:38.774 So how on earth would one of these guys 0:05:38.798,0:05:41.243 end up in the High Arctic? 0:05:41.719,0:05:44.506 Well, scientists have known[br]for a long time, turns out, 0:05:44.530,0:05:47.092 even before Natalia's discovery, 0:05:47.116,0:05:52.734 that camels are actually[br]originally American. 0:05:52.758,0:05:58.458 (Music: The Star Spangled Banner) 0:05:58.482,0:05:59.941 (Laughter) 0:05:59.965,0:06:01.496 They started here. 0:06:01.520,0:06:06.354 For nearly 40 of the 45 million years[br]that camels have been around, 0:06:06.378,0:06:09.537 you could only find them in North America, 0:06:09.561,0:06:12.814 around 20 different species, maybe more. 0:06:12.838,0:06:16.083 (Audio) LN: If I put them all in a lineup,[br]would they look different? 0:06:16.107,0:06:18.734 NR: Yeah, so you're going[br]to have different body sizes. 0:06:18.758,0:06:21.052 You're going to have some[br]with really long necks, 0:06:21.076,0:06:23.321 so they're actually[br]functionally like giraffes. 0:06:23.345,0:06:26.416 LN: Some had snouts, like crocodiles. 0:06:26.440,0:06:29.995 (Audio) NR: The really primitive,[br]early ones would have been really small, 0:06:30.360,0:06:32.552 almost like rabbits. 0:06:32.576,0:06:35.423 LN: What? Rabbit-sized camels? 0:06:35.447,0:06:36.884 (Audio) NR: The earliest ones. 0:06:36.908,0:06:39.582 And so those ones you probably[br]would not recognize. Yeah. 0:06:39.606,0:06:41.567 LN: Oh my God, I want a pet rabbit-camel. 0:06:41.591,0:06:43.598 (Audio) NR: I know,[br]wouldn't that be great? 0:06:44.645,0:06:47.636 LN: And then about three[br]to seven million years ago, 0:06:47.660,0:06:50.345 one branch of camels[br]went down to South America, 0:06:50.369,0:06:53.114 where they became llamas and alpacas, 0:06:53.138,0:06:56.060 and another branch crossed over[br]the Bering land bridge 0:06:56.084,0:06:57.520 into Asia and Africa. 0:06:57.544,0:06:59.965 And then around the end[br]of the last ice age, 0:06:59.989,0:07:03.361 North American camels went extinct. 0:07:03.893,0:07:06.313 So scientists knew all of that already, 0:07:06.337,0:07:12.413 but it still doesn't fully explain[br]how Natalia found one so far north. 0:07:12.437,0:07:17.111 Like, this is, temperature-wise,[br]the polar opposite of the Sahara. 0:07:17.135,0:07:19.675 Now, to be fair, 0:07:19.699,0:07:22.405 three and half million years ago,[br]it was on average 0:07:22.429,0:07:25.576 22 degrees Celsius warmer than it is now. 0:07:25.600,0:07:28.425 So it would have been boreal forest, 0:07:28.449,0:07:32.829 so more like the Yukon or Siberia today. 0:07:32.853,0:07:36.559 But still, like, they would have[br]six-month-long winters 0:07:36.583,0:07:38.806 where the ponds would freeze over. 0:07:38.830,0:07:40.298 You'd have blizzards. 0:07:40.322,0:07:44.606 You'd have 24 hours a day[br]of straight darkness. 0:07:44.630,0:07:46.938 Like, how? How? 0:07:46.962,0:07:51.120 How is it that one of these[br]Saharan superstars 0:07:51.144,0:07:54.375 ever have survived[br]those arctic conditions? 0:07:54.399,0:07:57.375 (Laughter) 0:07:57.399,0:08:01.295 Natalia and her colleagues[br]think they have an answer, 0:08:01.632,0:08:04.073 and it's kind of brilliant. 0:08:04.700,0:08:09.241 What if the very features that we imagine 0:08:09.265,0:08:13.225 make the camel so well-suited[br]to places like the Sahara 0:08:13.249,0:08:16.923 actually evolved to help it[br]get through the winter? 0:08:17.448,0:08:22.145 What if those broad feet were meant[br]to tromp not over sand 0:08:22.169,0:08:25.189 but over snow, like a pair of snowshoes? 0:08:25.792,0:08:28.593 What if that hump --[br]which, huge news to me, 0:08:28.617,0:08:30.991 does not contain water, it contains fat -- 0:08:31.015,0:08:32.594 (Laughter) 0:08:32.618,0:08:36.404 was there to help the camel[br]get through that six-month-long winter, 0:08:36.428,0:08:37.920 when food was scarce? 0:08:37.944,0:08:41.657 And then, only later, long after[br]it crossed over the land bridge 0:08:41.681,0:08:46.344 did it retrofit those winter features[br]for a hot desert environment? 0:08:46.368,0:08:50.197 Like, for instance, the hump[br]may be helpful to camels in hotter climes 0:08:50.221,0:08:52.839 because having all your fat in one place, 0:08:52.863,0:08:55.458 like a, you know, fat backpack, 0:08:55.482,0:08:58.141 means that you don't have[br]to have that insulation 0:08:58.165,0:08:59.793 all over the rest of your body. 0:08:59.817,0:09:02.531 So it helps heat dissipate easier. 0:09:02.555,0:09:05.396 It's this crazy idea, 0:09:05.420,0:09:10.967 that what seems like proof of the camel's[br]quintessential desert nature 0:09:10.991,0:09:15.030 could actually be proof[br]of its High Arctic past. 0:09:15.832,0:09:19.666 Now, I'm not the first person[br]to tell this story. 0:09:19.690,0:09:24.515 Others have told it as a way[br]to marvel at evolutionary biology 0:09:24.539,0:09:27.990 or as a keyhole into the future[br]of climate change. 0:09:28.855,0:09:31.299 But I love it for a totally[br]different reason. 0:09:31.751,0:09:34.513 For me, it's a story about us, 0:09:34.537,0:09:36.505 about how we see the world 0:09:36.529,0:09:39.060 and about how that changes. 0:09:39.658,0:09:43.030 So I was trained as a historian. 0:09:43.054,0:09:47.307 And I've learned that actually[br]a lot of scientists are historians, too. 0:09:47.331,0:09:48.880 They make sense of the past. 0:09:48.904,0:09:54.229 They tell the history of our universe,[br]of our planet, of life on this planet. 0:09:54.741,0:09:59.014 And as a historian, you start[br]with an idea in your mind 0:09:59.038,0:10:00.769 of how the story goes. 0:10:01.196,0:10:03.681 (Audio) NR: We make up stories,[br]and we stick with it, 0:10:03.705,0:10:05.428 like the camel in the desert, right? 0:10:05.452,0:10:07.897 That's a great story![br]It's totally adapted for that. 0:10:07.921,0:10:10.150 Clearly, it always lived there. 0:10:10.174,0:10:14.476 LN: But at any moment, you could[br]uncover some tiny bit of evidence. 0:10:14.500,0:10:16.699 You could learn some tiny thing 0:10:16.723,0:10:20.682 that forces you to reframe[br]everything you thought you knew. 0:10:20.706,0:10:24.484 Like, in this case, this one scientist[br]finds this one shard 0:10:24.508,0:10:26.255 of what she thought was wood, 0:10:26.279,0:10:31.317 and because of that, science has a totally[br]new and totally counterintuitive theory 0:10:31.341,0:10:34.956 about why this absurd,[br]Dr. Seuss-looking creature 0:10:34.980,0:10:36.512 looks the way it does. 0:10:36.536,0:10:41.940 And, for me, it completely upended[br]the way I think of the camel. 0:10:41.964,0:10:46.346 It went from being[br]this ridiculously niche creature 0:10:46.370,0:10:48.719 suited only to this[br]one specific environment, 0:10:48.743,0:10:51.983 to being this world traveler 0:10:52.007,0:10:54.031 that just happens to be in the Sahara 0:10:54.055,0:10:57.404 and could end up virtually anywhere. 0:10:57.880,0:11:02.880 (Applause) 0:11:14.396,0:11:16.134 This is Azuri. 0:11:16.589,0:11:19.469 Azuri, hi, how are you doing? 0:11:19.493,0:11:22.040 OK, here, I've got[br]one of these for you here. 0:11:24.135,0:11:28.318 So Azuri is on a break[br]from her regular gig 0:11:28.342,0:11:30.565 at the Radio City Music Hall. 0:11:30.589,0:11:32.738 (Laughter) 0:11:32.762,0:11:34.344 That's not even a joke. 0:11:34.717,0:11:36.454 Anyway -- 0:11:36.478,0:11:40.835 But really, Azuri is here[br]as a living reminder 0:11:40.859,0:11:43.677 that the story of our world 0:11:43.701,0:11:45.106 is a dynamic one. 0:11:45.130,0:11:49.837 It requires our willingness[br]to readjust, to reimagine. 0:11:49.861,0:11:54.138 (Laughter) 0:11:54.162,0:11:55.613 Right, Azuri? 0:11:55.637,0:12:02.053 And really that we're all[br]just one shard of bone away 0:12:02.077,0:12:04.307 from seeing the world anew. 0:12:04.926,0:12:06.086 Thank you very much. 0:12:06.110,0:12:14.679 (Applause)