WEBVTT 1 00:00:00.640 --> 00:00:03.759 Welcome missus Marsha for Radio Eye and to day I 2 00:00:03.799 --> 00:00:07.879 will be reading National Geographic Magazine dated February twenty twenty five. 3 00:00:08.560 --> 00:00:11.279 As a reminder, Radio Eye is a reading service intended 4 00:00:11.279 --> 00:00:14.240 for people who are blind or have other disabilities that 5 00:00:14.320 --> 00:00:17.800 make it difficult to read printed material. Please join me 6 00:00:17.879 --> 00:00:20.679 now for the first article titled The Hunt for the 7 00:00:20.760 --> 00:00:26.719 Other Humans by Brook Larmer. Stunning discoveries and fresh breakthroughs 8 00:00:26.719 --> 00:00:30.519 in DNA analysis are rewriting the evolutionary history of our 9 00:00:30.559 --> 00:00:33.759 species and offering in the picture of the mysterious other 10 00:00:33.920 --> 00:00:38.159 humans that our ancestors met as they fanned out across 11 00:00:38.359 --> 00:00:42.320 Europe and Asia. Deep inside Cobra Cave in the remote 12 00:00:42.320 --> 00:00:46.200 mountains of northeastern Laos, the beam from Eirak Suzoni's head 13 00:00:46.280 --> 00:00:49.600 lamp bounced across beer and rock until it flashed on 14 00:00:49.679 --> 00:00:52.920 something unusual, dozens of bones and teeth protruding from a 15 00:00:53.000 --> 00:00:56.719 layer of sediment and rock. Suzoni, a tall, fifty year 16 00:00:56.759 --> 00:00:59.679 old heathing specialist with a tiger tattoo on his arm, 17 00:01:00.200 --> 00:01:04.079 galed out to his partner, Sebastian fran Dieu. This was 18 00:01:04.120 --> 00:01:08.120 the French explorer's first foray into Cobra Cave. They had 19 00:01:08.159 --> 00:01:12.000 just scaled sixty five feet of limestone cliff, ascending from 20 00:01:12.000 --> 00:01:16.000 the forest floor to the cave's entrance with their unlikely companions, 21 00:01:16.400 --> 00:01:19.799 a pair of local teenagers in foot clubs. The Long 22 00:01:19.920 --> 00:01:22.879 Boys knew the terrain around the cave and the name 23 00:01:23.000 --> 00:01:27.480 Saint Cobras that sometimes lurked inside. To day, the snakes 24 00:01:27.480 --> 00:01:30.200 went nowhere to be seen, but soon after climbing into 25 00:01:30.200 --> 00:01:33.280 the cave, the explorers had stumbled upon what appeared to 26 00:01:33.319 --> 00:01:38.599 be a trove of ancient apostles. Suzoni and frong Dieu 27 00:01:38.760 --> 00:01:41.760 were scouting this cave for an international team of paleo 28 00:01:41.840 --> 00:01:46.120 anthropologists excavating sites nearby. For more than fifteen years, the 29 00:01:46.159 --> 00:01:50.040 scientists had been digging in these mountains, searching for clues 30 00:01:50.040 --> 00:01:53.120 to some of the deepest mysteries of human evolution. When 31 00:01:53.159 --> 00:01:56.760 did Homo sapiens arrive here and what other humans did 32 00:01:56.840 --> 00:02:00.840 they enter? Suzoni didn't dare touch the uscis at first, 33 00:02:01.079 --> 00:02:03.159 but when he returned to survey the cave the next 34 00:02:03.200 --> 00:02:06.719 day with one of the research team's geologists, his task 35 00:02:06.879 --> 00:02:09.439 was to pry loose the sample of the sediment from 36 00:02:09.439 --> 00:02:12.599 the cave wall as he tapped on a chisel, A 37 00:02:12.680 --> 00:02:16.919 large brown tooth tumbled out, a molar that looked early human. 38 00:02:17.479 --> 00:02:21.520 Suzoni hadn't intended to make a fine by protocol and profession, 39 00:02:21.639 --> 00:02:24.120 that was the scientist's job, but he marveled at the 40 00:02:24.159 --> 00:02:27.080 specimen for a moment and slipped it into his shirt pocket. 41 00:02:27.560 --> 00:02:31.479 It was, he says, a beautiful gift. Back at base camp, 42 00:02:31.520 --> 00:02:37.759 Suzoni huddled with the research team's leader, paleo anthropologist Fabrese 43 00:02:37.960 --> 00:02:42.280 Demder through the University of Copenhagen, and Namont de Zenotte, 44 00:02:42.800 --> 00:02:46.159 an expert in arcade teeth through the University of Bordeaux. 45 00:02:46.759 --> 00:02:50.879 Suzoni carefully described what he'd seen up in Cobra Cave 46 00:02:52.599 --> 00:02:55.439 and showed them a few animal teeth he'd pulled from 47 00:02:55.439 --> 00:02:58.759 the sediment. Then he reached first pocket. Oh, I brought 48 00:02:58.800 --> 00:03:02.240 something for you, Sozoni's with a grin. Zanoli, wearing an 49 00:03:02.280 --> 00:03:05.360 Indiana Jones's hat, leaned in for a close look. The 50 00:03:05.400 --> 00:03:09.199 tooth was completely unworn, well preserved. He remembers, I knew 51 00:03:09.240 --> 00:03:12.199 immediately that it was human, but what kind of human? 52 00:03:12.599 --> 00:03:14.719 It was too big and rippled. He thought to have 53 00:03:14.800 --> 00:03:18.680 come from a modern hopo. Some Homo sapiens, and though 54 00:03:18.680 --> 00:03:22.919 it superficially resembled a Neanderthal tooth, remains of that species 55 00:03:22.960 --> 00:03:28.120 had never been definitively identified. In East Asia, the scientists 56 00:03:28.159 --> 00:03:31.759 exchanged baffled books. Who was the owner of this mysterious tooth? 57 00:03:32.479 --> 00:03:35.560 A molar in Laos, a jawbone on the Tibetan Plateau, 58 00:03:36.039 --> 00:03:39.919 the fragment of a pinky in Siberia. Our evolutionary history 59 00:03:40.000 --> 00:03:44.520 is now being rewritten by tiny discoveries, immuminated by past 60 00:03:44.840 --> 00:03:49.639 advancing science breakthroughs in active genetics, the study of proteins, 61 00:03:49.680 --> 00:03:54.080 and radioactive dating. The flood of new insights is not 62 00:03:54.120 --> 00:03:57.719 only radically changing the understanding of our origins, it is 63 00:03:57.800 --> 00:03:59.840 challenging the very notion of what it means to be. 64 00:04:00.879 --> 00:04:03.599 All of us, all eight billion people on this planet, 65 00:04:03.680 --> 00:04:08.400 belong to a single species. We Homo sapiens, are the 66 00:04:08.479 --> 00:04:12.120 last prominens on her. Not long ago, it was widely 67 00:04:12.159 --> 00:04:15.800 believed that modern humans followed a relatively straight caff of 68 00:04:15.919 --> 00:04:19.600 evolutionary progress, as we found out of Africa, one that 69 00:04:19.759 --> 00:04:24.439 was separate from and implicitly superior to that of other species. 70 00:04:25.040 --> 00:04:28.240 Given today, one of the most indelible images of evolution 71 00:04:28.439 --> 00:04:32.160 is the so called March of progress, an illustration plastered 72 00:04:32.199 --> 00:04:35.720 on t shirts and posters that shows our predecessors improving 73 00:04:35.720 --> 00:04:40.120 their posture as they progress inexorably to Homo sapiens paul 74 00:04:40.160 --> 00:04:44.000 and proud striding into the future. The current upheaval and 75 00:04:44.120 --> 00:04:48.120 evolutionary thinking has shattered that neat linear view of human 76 00:04:48.240 --> 00:04:51.399 origins and begun to replace it with a far more 77 00:04:51.439 --> 00:04:55.839 tangled picture. What researchers now know is that between seventy 78 00:04:55.920 --> 00:04:59.279 thousand and forty thousand years ago, a critical period in 79 00:04:59.319 --> 00:05:03.240 our evolution their development, the world teemed with human variety, 80 00:05:03.680 --> 00:05:07.079 and as Homo Sapiens radiated out across Europe and Asia, 81 00:05:07.199 --> 00:05:10.360 they countered and at times even mated with other types 82 00:05:10.399 --> 00:05:15.519 of humans. Evidence of this commingling came in twenty ten 83 00:05:16.000 --> 00:05:22.720 when Swedish paleogeneticists Savante Paabo Bob napped the Neanderthal genome 84 00:05:22.759 --> 00:05:26.040 for the first time. His work proved that Neanderthals and 85 00:05:26.040 --> 00:05:29.720 Homo Sapiens pro created, and that the genetic exchange had 86 00:05:29.720 --> 00:05:33.399 profound in lasting consequences to day. More than forty thousand 87 00:05:33.480 --> 00:05:37.879 years after the Neanderthals went extinct, most human beings alive 88 00:05:38.040 --> 00:05:41.279 curing remnants of their DNA. But who else shared the 89 00:05:41.279 --> 00:05:44.240 planet with us? And how did our interactions with these 90 00:05:44.240 --> 00:05:47.600 other humans shape the course of our own evolution and 91 00:05:47.680 --> 00:05:52.879 their extinction. Paleo Anthropologists are delving ever deeper into these questions, 92 00:05:53.199 --> 00:05:56.399 the same ones that Demeter and Zenoli faced as they 93 00:05:56.439 --> 00:06:00.639 studied the mysterious tooth from Probuncaid. One of the most 94 00:06:00.639 --> 00:06:04.120 revealing clues came from a cave in Siberia near Russia's 95 00:06:04.120 --> 00:06:09.639 bordered with Kazakhstan, where researchers uncovered a pinky fragment no 96 00:06:10.279 --> 00:06:14.839 larger than a pea. The frigid temperatures in Denisovak kay 97 00:06:15.079 --> 00:06:19.879 had preserved ancient DNA in Deanderthal fossils discovered there, but 98 00:06:20.000 --> 00:06:23.240 this bone, more than sixty thousand years old, was different. 99 00:06:23.480 --> 00:06:27.199 When Pavo and his team analyzed its DNA, they came 100 00:06:27.199 --> 00:06:30.920 to a stunning realization. The fossil belonged to a completely 101 00:06:31.000 --> 00:06:36.600 unknown and banished human species. The Denisovans, as Pabo's team 102 00:06:36.720 --> 00:06:40.439 dubbed them, became the first human group ever identified solely 103 00:06:40.480 --> 00:06:44.199 through DNA, A ghost species, as at Spurts call those 104 00:06:44.279 --> 00:06:49.360 without a physical identity. Denisovakave yielded more fossils with their DNA. 105 00:06:49.959 --> 00:06:52.040 These included a bone from a girl who had a 106 00:06:52.120 --> 00:06:56.800 Denisovan father and a Neanderthal mother, the only first generation 107 00:06:57.000 --> 00:07:02.319 hybrid kminin ever discovered from the finger fragment. Genusis were 108 00:07:02.360 --> 00:07:06.199 able to trace Denysovan DNA in modern day populations all 109 00:07:06.199 --> 00:07:10.079 over the world, from Iceland to Peru, with especially high 110 00:07:10.160 --> 00:07:14.480 concentrations in Papua New Guinea fifty five hundred miles away 111 00:07:14.560 --> 00:07:20.519 from Denizova Cave. Homo sapiens almost certainly interbred with Denysovans 112 00:07:20.879 --> 00:07:24.439 as well as Neanderthals and carried their DNA across the planet. 113 00:07:24.959 --> 00:07:29.360 The paleo anthropologists now believed these gene flow events were 114 00:07:29.439 --> 00:07:33.480 not an anomaly, but a central feature of evolution, helping 115 00:07:33.519 --> 00:07:37.240 Homo sapiens adapt to new environments and leaving most of 116 00:07:37.319 --> 00:07:40.839 us with a direct biological length to extinct groups of 117 00:07:40.920 --> 00:07:45.240 ancient humans. For all the advances in genetic and protein 118 00:07:45.279 --> 00:07:50.240 research understanding how Denysiban genes made it to Papua in 119 00:07:50.240 --> 00:07:54.879 the Guinea, or why Neanderthals and Denysovans after nearly half 120 00:07:54.879 --> 00:07:59.000 a million years of existence, disappeared, once Homo sapiens arrived 121 00:07:59.360 --> 00:08:03.360 will require more fragments of ancient bones and teeth. After 122 00:08:03.399 --> 00:08:05.720 more than a century of digging, the fossil record of 123 00:08:05.720 --> 00:08:10.360 our best known relative, Neanderthals is comparatively sparse, bones from 124 00:08:10.399 --> 00:08:16.519 about four hundred individuals. The Denisovan record is vanishingly small. 125 00:08:16.920 --> 00:08:20.319 All of the Denisovan fossils ever found could fit into 126 00:08:20.319 --> 00:08:23.319 a bread box, and they would still be room for bagels. 127 00:08:24.240 --> 00:08:28.199 High on the Tibetan Plateau in China's Gansu Province, in 128 00:08:28.240 --> 00:08:30.800 a cave hollowed out of a cliff some eleven thousand 129 00:08:30.800 --> 00:08:34.080 feet above sea level, a Buddhist prayer site, has become 130 00:08:34.120 --> 00:08:38.559 a remarkable locus of scientific discovery. Long before the bones 131 00:08:38.600 --> 00:08:44.559 found their acquired modern value to modern researchers, they were 132 00:08:44.600 --> 00:08:48.000 ground to make medicines and elixirs. Suits. Perhaps something of 133 00:08:48.039 --> 00:08:52.559 a miracle that an ancient jawbone found in Vaishia Karst 134 00:08:52.720 --> 00:08:57.840 Cave in nineteen eighty, now commonly known as the Shahi Mandible, 135 00:08:58.039 --> 00:09:03.000 still survives. The monk who discovered it brought the bone 136 00:09:03.039 --> 00:09:07.120 to its leader, the sixth Bungtang living Buddha, who bequeathed 137 00:09:07.159 --> 00:09:10.840 it to Chinese scientists. The mandible sat on a shell 138 00:09:10.960 --> 00:09:14.559 for years unidentified and almost forgotten. But several years ago, 139 00:09:14.639 --> 00:09:20.279 inspired by the discoveries in Siberia, Lanchu University archeologist dong 140 00:09:20.399 --> 00:09:24.600 Ju Zhang joined some colleagues in trying to solve the 141 00:09:24.679 --> 00:09:27.960 riddle of the bone's identity. Then in her mid thirties, 142 00:09:27.960 --> 00:09:31.000 the bone had been languishing at the university for almost 143 00:09:31.080 --> 00:09:35.200 as long as she'd been alive. Zang initiated a delicate 144 00:09:35.279 --> 00:09:40.559 excavation in Vai Shia Karst Cave alongside the meditating monks, 145 00:09:40.600 --> 00:09:45.000 but obstacles abounded. The jabon's muddled world history didn't specify 146 00:09:45.039 --> 00:09:48.720 exactly where in the cave it had been found. Even 147 00:09:48.759 --> 00:09:52.440 more confounding, the jabone had no trace of DNA. The 148 00:09:52.480 --> 00:09:56.639 only information came from the carbonate crust still clinging to it, 149 00:09:56.960 --> 00:10:00.879 which uranium thorium dating estimated to be at least one 150 00:10:00.960 --> 00:10:05.000 hundred sixty thousand years old. The jaw boone was by 151 00:10:05.039 --> 00:10:08.320 far the earliest trace of human presence ever discovered on 152 00:10:08.399 --> 00:10:12.519 the Tibetan planteau. Intriguing, yes, but it got Zong no 153 00:10:12.679 --> 00:10:15.559 closer to identifying the fossil. On a work trip to 154 00:10:15.600 --> 00:10:19.000 Europe in mid twenty sixteen, Zong, either for help, met 155 00:10:19.039 --> 00:10:22.720 with a graduate student experimenting with a method of analysis 156 00:10:22.720 --> 00:10:26.919 that promised to go beyond DNA. Grido Velger was just 157 00:10:27.000 --> 00:10:29.480 twenty five, but he was already breaking new ground in 158 00:10:29.559 --> 00:10:35.320 the developing field paleo proteomics, which functions like a deep 159 00:10:35.399 --> 00:10:39.080 time machine. Its hustle haired. The Dutchman explained to Zong 160 00:10:39.480 --> 00:10:43.639 how he analyzed ancient proteins that persistent fossils far longer 161 00:10:43.679 --> 00:10:48.519 than DNA, sometimes two million years longer. Proteins follow patterns 162 00:10:48.559 --> 00:10:51.720 set by a DNA, so they act like shadow of DNA, 163 00:10:51.879 --> 00:10:56.159 echoing information long after the origin was gone. Still, Velger 164 00:10:56.440 --> 00:11:00.919 warned Zong that extracting proteins is typically in asive. A 165 00:11:01.000 --> 00:11:03.879 whole must be drilled into the fossil, and there is 166 00:11:03.919 --> 00:11:07.960 no guarantee of success. I felt a huge responsibility for 167 00:11:08.000 --> 00:11:11.039 this precious artifact, Zong recalls, But we needed to find 168 00:11:11.039 --> 00:11:13.279 out what it was, and I was out of options. 169 00:11:13.840 --> 00:11:18.519 Zong's last resource eventually became Welger's first big chance, what 170 00:11:18.600 --> 00:11:22.320 he calls a scientific opportunity for his nascent field. The 171 00:11:22.360 --> 00:11:26.240 protein material was extracted in China. Zong recalls how nervous 172 00:11:26.240 --> 00:11:28.919 she was handing over the mandible to be Drive and 173 00:11:29.000 --> 00:11:32.440 Belcher and now at the University of Copenhagen, then analyzed 174 00:11:32.480 --> 00:11:36.120 it with a mass spectrometer in the German lab. The 175 00:11:36.200 --> 00:11:39.519 patterns of the collagen protein found in the jawbone confirmed 176 00:11:39.519 --> 00:11:43.360 that the fossil was in fact Denisovin. The revelation marked 177 00:11:43.399 --> 00:11:46.759 the first time an ancient human had been identified solely 178 00:11:46.879 --> 00:11:50.759 through proteins. The jaw moreover, was the first evidence of 179 00:11:50.879 --> 00:11:56.519 Denisovan's existing outside that of Denisova Cave, enriching the picture 180 00:11:56.799 --> 00:12:00.159 of a species about which nearly nothing was known. Y 181 00:12:00.200 --> 00:12:03.279 Thoris have continued in the story of the Dimissivans in 182 00:12:03.360 --> 00:12:07.519 the Tibetan Planteau Cave has grown more detailed. A year 183 00:12:07.600 --> 00:12:10.840 after their discovery, Zong and her team found traces of 184 00:12:10.919 --> 00:12:16.960 Dimissovan DNA and Vaishia Karst cave, further confirming their presence there. 185 00:12:17.720 --> 00:12:20.679 Last summer of velter and as Chinese colleagues again used 186 00:12:21.000 --> 00:12:27.879 proteo proteomics and the dimisipan ribon to show that Dimisivans 187 00:12:28.200 --> 00:12:30.559 had inhabited the cave off and on for more than 188 00:12:30.559 --> 00:12:34.559 one hundred thousand years, butchering and consuming a wide range 189 00:12:34.600 --> 00:12:37.360 of wild animals. Adding a piece of a puzzle is 190 00:12:37.360 --> 00:12:41.000 a unique experience, says Velper, because every new piece changes 191 00:12:41.039 --> 00:12:45.600 the arrangement of all the rest. Belcher's point about how 192 00:12:45.639 --> 00:12:48.879 one discovery can change the meaning of another is underscored 193 00:12:48.919 --> 00:12:51.879 by the jawbone that he and Zong revealed. Their work 194 00:12:51.919 --> 00:12:56.240 identifying the mandible meant that dinisivants now had an anchor point, 195 00:12:56.679 --> 00:12:59.360 a bone that would serve as a basis of compurison 196 00:12:59.759 --> 00:13:03.320 for other fossils would have found in a dusty Chinese collection, 197 00:13:03.639 --> 00:13:07.039 or say, in a cave in Laos. This is precisely 198 00:13:07.120 --> 00:13:11.159 what Verbreece Demeter needed. He'd been carrying around the mysterious 199 00:13:11.200 --> 00:13:14.759 molar from Cobra Cave, trying to find ways to extract 200 00:13:14.759 --> 00:13:18.279 information from it. That no viable DNA could be found 201 00:13:18.279 --> 00:13:22.919 in the tooth. Not even plio proteomics could help, as 202 00:13:22.960 --> 00:13:26.279 the tooth's proteins were too limited for a conclusive reading. 203 00:13:26.879 --> 00:13:29.759 The only thing Demeter could determine was that the tooth 204 00:13:29.919 --> 00:13:33.440 was human and belonged one hundred and sixty millennia ago 205 00:13:33.799 --> 00:13:36.799 to a young girl. But when he learned that Zong 206 00:13:36.879 --> 00:13:40.000 and Belger were set to publish a journal article unveiling 207 00:13:40.039 --> 00:13:44.240 the Demissian javo. Demeter knew Key and Zanoli, the tooth expert, 208 00:13:44.600 --> 00:13:47.080 could compare their molar with the two teeth on the javo. 209 00:13:47.639 --> 00:13:50.080 They discovered that one of the teeth was almost identical 210 00:13:50.120 --> 00:13:53.919 to the Cobra Cave molar. It was a morphological match, 211 00:13:54.320 --> 00:13:58.159 not in the disputable genetic one. But Demeter felt indicated 212 00:13:58.679 --> 00:14:01.000 maybe we had some luck me last year as his 213 00:14:01.120 --> 00:14:04.240 team gathered at the Laos Cave site. But we've been 214 00:14:04.279 --> 00:14:07.279 digging here for twenty one years now our work is 215 00:14:07.320 --> 00:14:11.159 finally paying off. Cobra Cave marks the third place in 216 00:14:11.159 --> 00:14:14.399 the world where admissiban fossile has been found. It is 217 00:14:14.440 --> 00:14:19.879 also the first one discovered in a subtrop for gulp environment, 218 00:14:20.000 --> 00:14:23.480 about one thousand miles south of the high altitude Baishia 219 00:14:23.759 --> 00:14:27.600 Karst Cave on the Tibetan Plateau and two thousand miles 220 00:14:27.600 --> 00:14:32.399 southeast of the frigid Denisova Cave, suggesting that Dnissobam has 221 00:14:32.519 --> 00:14:36.519 roamed widely and adapted to many different environments. As more 222 00:14:36.639 --> 00:14:41.200 dinisiban geographic markers are confined confirmed, and as their location 223 00:14:41.360 --> 00:14:45.039 and timeline continue to overlap with those of other comminins, 224 00:14:45.080 --> 00:14:49.440 in particular Neanderthals and Homo sapiens. More genetic puzzle pieces 225 00:14:49.519 --> 00:14:53.879 fall into place. In twenty fourteen, five years before the 226 00:14:54.000 --> 00:14:59.799 Jahi Mandibal was identified as Dimisipan, population geneticist Amelia where 227 00:15:00.200 --> 00:15:03.960 Sanche's at Brown University made a surprising discovery about the 228 00:15:04.000 --> 00:15:08.919 ancient DNA. She found that the gene known as epas one, 229 00:15:09.000 --> 00:15:13.519 which helps Tibetans live comfortably at high altitude without getting hypoxia, 230 00:15:14.120 --> 00:15:18.879 came not from modern humans but from dinyicipans. Thinking from 231 00:15:18.960 --> 00:15:22.639 the Denizobev CAD gave her the only nearly perfect DNA 232 00:15:22.759 --> 00:15:27.200 match when Belcher and Zong confirmed that in nineteen twenty. 233 00:15:28.039 --> 00:15:32.240 In twenty nineteen that dinisibants had inhabited the Tibetan plateau, 234 00:15:32.759 --> 00:15:36.399 the connection made perfect. Set Tibetans put this gene to use. 235 00:15:36.720 --> 00:15:39.960 Who at de Sanchez says, even though they carry only 236 00:15:40.000 --> 00:15:43.799 a small remnant of Dinisovant DNA and arrived on the 237 00:15:43.840 --> 00:15:47.799 plateau tens of thousands of years after the interbreeding took place. 238 00:15:48.399 --> 00:15:51.080 You don't need a lot of our DNA for it 239 00:15:51.120 --> 00:15:54.600 to be beneficial or useful. Later on, says the Reta Sanchez, 240 00:15:54.919 --> 00:15:58.919 who is now studying the dinisivant gene prevalent Indian Americas. 241 00:15:59.399 --> 00:16:02.039 Even a small amount, she says, has a huge impact 242 00:16:02.120 --> 00:16:07.120 on people, as it did with Tibetans. The consequences of 243 00:16:07.240 --> 00:16:11.799 ancient ingebreeding are still poorly understood, but geneticists like where 244 00:16:11.840 --> 00:16:17.320 To Sanchez believe it serve a vital evolutionary purpose. That 245 00:16:17.519 --> 00:16:21.320 only did all that mating inject much heated genetic diversity 246 00:16:21.399 --> 00:16:25.840 into Homo sapianst populations, The gene flow gave modern humans 247 00:16:26.159 --> 00:16:30.840 evolutionary shortcuts to adapt more quickly to extreme environments, staving 248 00:16:30.879 --> 00:16:34.799 off hypoxia inti PET for example. This bolstering of the 249 00:16:34.799 --> 00:16:38.960 immune system likely helped Homo Sapiens spread across the world, 250 00:16:39.639 --> 00:16:43.000 but the impact hasn't all been good, scientists finding that 251 00:16:43.039 --> 00:16:46.919 some of the genes inherited from Neanderthals and Dimicivans are 252 00:16:46.919 --> 00:16:52.039 associated with depression, autism, or obesity. Ingebrading. Moreover, didn't seem 253 00:16:52.039 --> 00:16:56.120 to help the Neanderthals and dimyicibans, though remnants of their 254 00:16:56.200 --> 00:16:59.559 DNA live on within us. Their genomes show no trace 255 00:16:59.600 --> 00:17:03.080 of modern humans, and some scientists believe that interbreeding in 256 00:17:03.120 --> 00:17:07.799 the Homo Sapiens may even have hastened their demise. Ludovic 257 00:17:07.960 --> 00:17:11.720 Slimoch is obsessed with the moment when Homo sapiens might 258 00:17:11.759 --> 00:17:15.640 have pushed others human species out of the evolutionary picture. 259 00:17:16.240 --> 00:17:21.319 The French paleo anthropologist with the University of Toulouse third 260 00:17:21.839 --> 00:17:24.920 has chased the ghosts of Neanderthals from the Horn of 261 00:17:24.960 --> 00:17:28.880 Africa to the Xerto for the past quarter century, and 262 00:17:28.920 --> 00:17:33.160 his wife, archaeologists Glorimetts, have spent much of their time 263 00:17:33.559 --> 00:17:37.599 digging and thinking in grout Mandarin, a paved in south 264 00:17:38.279 --> 00:17:41.799 in southern France, inhabited at different times more than forty 265 00:17:41.799 --> 00:17:44.839 two thousand years ago by Homo sapiens and some of 266 00:17:44.880 --> 00:17:48.359 the last Neanderthals. It's just a small rock overhang, but 267 00:17:48.440 --> 00:17:51.920 the human story it tells is really universal, says Silmach. 268 00:17:52.400 --> 00:17:54.839 I use Neandertales as a mirror to try to see 269 00:17:54.880 --> 00:17:59.359 ourselves more clearly. Slimoch, bearded in the Barefoot, is halfway 270 00:17:59.400 --> 00:18:03.599 through an anime Lady Siloti on the Neanderthal extinction. When 271 00:18:03.640 --> 00:18:06.359 his seven year old son bursts into their twelfth century 272 00:18:06.400 --> 00:18:09.839 stone house in the foothills of the Pyrenees, Papa, look 273 00:18:09.920 --> 00:18:12.559 what I found. The boy drops a pile of bones 274 00:18:12.559 --> 00:18:15.640 onto the kitchen table. Slimoc jumps up in delight to 275 00:18:15.680 --> 00:18:18.359 inspect the hall the bones of the remains of a deer, 276 00:18:18.680 --> 00:18:21.279 and father and son piece them together into a skeleton. 277 00:18:21.799 --> 00:18:25.079 Slimoch sees himself reflected in his son. All my life, 278 00:18:25.119 --> 00:18:29.160 I've been on a quest for our origins. Slimoch's pursuit 279 00:18:29.200 --> 00:18:32.039 has led him to study the period when Homo sapiens 280 00:18:32.079 --> 00:18:37.319 emerged from Africa, entering territory inhabited by Neanderthals, nizebants, and 281 00:18:37.400 --> 00:18:42.880 other late hominins, the ghost species. This was a critical moment, 282 00:18:42.960 --> 00:18:45.359 the fifty two year old believes, when the last of 283 00:18:45.440 --> 00:18:48.720 these other pupmans were carrying out their own experiments in humanity, 284 00:18:49.200 --> 00:18:52.559 experienced that he strives to understand not just from a 285 00:18:52.599 --> 00:18:57.000 genetic perspective, but from a behavioral one too. Stirring around 286 00:18:57.039 --> 00:18:59.480 his office high in the raptors of his medieval home 287 00:19:00.559 --> 00:19:04.640 shows me stone flints found in brought Mandarin. When you 288 00:19:04.680 --> 00:19:08.240 take Neanderthal tools, each is unique, he says, pointing out 289 00:19:08.319 --> 00:19:11.839 the variations in shape, color, and size. Living in small, 290 00:19:11.880 --> 00:19:16.039 isolated groups across Europe, Neanderthals displayed a creativity and a 291 00:19:16.160 --> 00:19:20.920 sensitivity to their environment, quite unlike early Homo sapiens, whose 292 00:19:20.960 --> 00:19:24.319 tools and weapons were almost identical from the levant to 293 00:19:24.480 --> 00:19:29.039 Western europe Neanderthals, Slimmoch says, perceived and engaged with the 294 00:19:29.039 --> 00:19:32.799 world in lays profoundly different from those of Homo Sapiens. 295 00:19:33.400 --> 00:19:37.119 The discovery in brought Mandrin of one of the last 296 00:19:37.119 --> 00:19:41.279 Neanderthals in Europe, has prompted Slimok, a National geographic explorer, 297 00:19:41.680 --> 00:19:44.400 to think deeply about how the divergent natures of Homo 298 00:19:44.440 --> 00:19:48.519 sapiens and Neanderthals may have led to the latter's ultimate demise. 299 00:19:49.079 --> 00:19:53.160 The skeleton, which Slimoch named Thorin after the dwarf king 300 00:19:53.359 --> 00:19:56.519 in J. R. R. Tolkien's The Hobbit, was found a 301 00:19:56.559 --> 00:19:59.880 decade ago. Slimoch's team has been slowly unearthed in it 302 00:20:00.039 --> 00:20:03.480 ever since, using tweezers to remove grains of sand and 303 00:20:03.559 --> 00:20:07.279 fragments of bone. After nine years, they recovered parts of 304 00:20:07.319 --> 00:20:10.400 Thorign's skull, thirty one teeth, and a large number of 305 00:20:10.480 --> 00:20:14.400 tiny unidentified bones. The root of one tooth still had 306 00:20:14.759 --> 00:20:20.799 viable DNA, which yielded an astonishing insight. Just recently were unveiled. 307 00:20:21.200 --> 00:20:25.160 Thorn's group inhabited brout Mandarin about forty two thousand years 308 00:20:25.200 --> 00:20:28.119 ago and had been in genetic isolation for the previous 309 00:20:28.160 --> 00:20:32.079 fifty thousand years, never even mingling with other Neanderthals living 310 00:20:32.079 --> 00:20:35.680 a few valleys away. For Slimov, this was further evidence 311 00:20:35.680 --> 00:20:39.559 of a deeper Neanderthal lineage and of how different Neanderthals 312 00:20:39.839 --> 00:20:44.279 were from modern humans. Slimov believes the moment when Neanderthals 313 00:20:44.279 --> 00:20:48.079 and Homo sapiens finally encountered one another was a turning 314 00:20:48.119 --> 00:20:51.480 point in evolutionary history and one captured on the walls 315 00:20:51.480 --> 00:20:58.039 of brought Mandrian. His colleague, archaeologist Segunaine Vandeveld, analyzed the 316 00:20:58.079 --> 00:21:01.039 sub deposits left by cooking fires on the cave walls 317 00:21:01.319 --> 00:21:04.279 a kind, counting the rings on a tree, and found 318 00:21:04.359 --> 00:21:06.079 that the last fire in the part of the cave 319 00:21:06.200 --> 00:21:10.240 once inhabited by Neanderthals occurred less than a year before 320 00:21:10.279 --> 00:21:13.559 the first Homo Sapiens fire. Whether there was an actual 321 00:21:13.599 --> 00:21:17.680 physical encounter or not, Slimok believes this moment around forty 322 00:21:17.720 --> 00:21:20.640 two thousand years ago marked the point of no return 323 00:21:21.200 --> 00:21:24.119 that the Neanderthals disappeared at the same time the wave 324 00:21:24.200 --> 00:21:28.119 of Homo Sapiens arrived, was not, in Slimok's words, an 325 00:21:28.240 --> 00:21:32.960 unfortunate coincidence. Paleo Anthropologists have debated the cause of the 326 00:21:33.039 --> 00:21:36.599 Neanderthals extinction for years, and will surely do so with 327 00:21:36.720 --> 00:21:41.400 the Amisibans as their timeline and geographic spread become clearer. 328 00:21:42.960 --> 00:21:47.400 The Anisibans and Niagarthals seem to have vanished from the 329 00:21:47.440 --> 00:21:50.559 fossil record at roughly the same time. There is a 330 00:21:50.559 --> 00:21:55.519 growing consensus among paleo anthropologists that the Neanderthals disappearance owed 331 00:21:55.559 --> 00:22:00.960 primarily to a demographic crisis, a dwindling population, limited genetic 332 00:22:01.000 --> 00:22:05.000 diversity exacerbated by climate change, and the emergence of a 333 00:22:05.119 --> 00:22:09.359 powerful rival, Homeward Sapiens. Inch A. Breeding may have played 334 00:22:09.359 --> 00:22:13.200 a role too. Chris Stringer, a paleo anthropologist at the 335 00:22:13.279 --> 00:22:18.440 Natural History Museum in London and National Geographic Explorer, suggests 336 00:22:18.440 --> 00:22:22.400 that Neanderthal females may have been absorbed or abducted by 337 00:22:22.440 --> 00:22:26.599 dominant Sapiens groups, pushing Neanderthals to the edge of the 338 00:22:26.640 --> 00:22:31.759 demographic abyss. The disappearance of the Neagarthals and Demizodines and 339 00:22:31.799 --> 00:22:35.319 other groups around forty thousand years ago marked the end 340 00:22:35.359 --> 00:22:38.759 of millions of years when multiple groups of Hammonen's walk theory. 341 00:22:39.359 --> 00:22:43.559 The current epoch is a historical anomaly, and Stringer advises 342 00:22:43.640 --> 00:22:46.559 us not to be smug in our status as the 343 00:22:46.640 --> 00:22:50.799 last one's standing. Neanderthals and Dimizibans survived for half a 344 00:22:50.799 --> 00:22:55.160 million years, Homo erectus lasted nearly two million years. At 345 00:22:55.200 --> 00:22:57.920 the rate we're going, how successful hull we looked in 346 00:22:58.039 --> 00:23:01.799 two thousand years must be less a million. As the 347 00:23:01.839 --> 00:23:04.759 sun sinks and the French sky Sliemaud steps out into 348 00:23:04.799 --> 00:23:07.839 the garden where his sons are jumping on a trampoline. 349 00:23:08.000 --> 00:23:11.000 His mind is still on the Neanderthal's demise, which he 350 00:23:11.079 --> 00:23:14.680 chooses not to attribute primarily to a changing climate or 351 00:23:14.720 --> 00:23:18.880 a demographic weakness. The moil Sapiens caused the Agartales to 352 00:23:19.000 --> 00:23:24.319 vanish almost instantaneously from the Annals of Archaeology. Slidnot says 353 00:23:25.559 --> 00:23:28.799 there's no need to deny our colonialist guilt, he says, 354 00:23:29.160 --> 00:23:31.559 or to seek solace in the strands of the Agartal 355 00:23:31.680 --> 00:23:34.960 DNA that live on inside us even after half a 356 00:23:34.960 --> 00:23:39.240 million years on the planet. The Neanderthal's creativity and isolation 357 00:23:39.720 --> 00:23:44.960 didn't stand a chance against Homosapien's hyper efficiency and social networking. 358 00:23:45.519 --> 00:23:50.079 This was, he had said, a fully fledged conquest. Back 359 00:23:50.160 --> 00:23:53.799 in a rice field in northeastern laws Erex Suzonia's leading 360 00:23:54.160 --> 00:23:57.000 A brist Demeter's team of scientists toward a new cave 361 00:23:57.119 --> 00:24:00.400 several miles north of their base camp. In the past 362 00:24:00.400 --> 00:24:03.880 two decades, the international team has worked on a single mountain, 363 00:24:04.039 --> 00:24:07.240 excavating a cluster of caves that has yielded a rare 364 00:24:07.599 --> 00:24:11.680 trifecta of ancient human species. In additions of discovering the 365 00:24:11.920 --> 00:24:15.720 nissoban rola, the team has unearthed postils of ancient Homo 366 00:24:15.759 --> 00:24:20.079 sapiens in one cave and in another of one hundred 367 00:24:20.119 --> 00:24:23.960 fifty thousand year old too, most likely from Homo erectus. 368 00:24:24.640 --> 00:24:27.839 This is an incredible result, but we're also looking at 369 00:24:27.880 --> 00:24:32.720 just one site, says Laura Shackelfert, an American pale anthropologist 370 00:24:32.799 --> 00:24:37.119 with the University of Illinois, Urbana Champagne and a National 371 00:24:37.119 --> 00:24:40.440 Geographic explorer who began working with the team in Laos 372 00:24:40.440 --> 00:24:43.680 in two thousand and eight. Dinizaban remains have to be 373 00:24:43.759 --> 00:24:46.359 all over the place, and we just haven't found them yet. 374 00:24:47.000 --> 00:24:49.680 The future of the distant pass seems to lie in Asia, 375 00:24:50.039 --> 00:24:53.400 a region that Demeter calls a blank slate compared to Europe. 376 00:24:53.720 --> 00:24:58.519 It started with the astonishing discovery of two diminutive habit populations, 377 00:24:58.920 --> 00:25:03.519 Homo floresiensis in Indonesia in two thousand and three and 378 00:25:03.640 --> 00:25:08.319 Homo luzon mensis in the Philippines in twenty nineteen. The 379 00:25:08.359 --> 00:25:13.039 focus has now shifted to China. Ever since the Jahi 380 00:25:13.400 --> 00:25:18.359 mandibal was identified in twenty nineteen, Chinese paleo anthropologists have 381 00:25:18.559 --> 00:25:23.039 raced can re examine the country's vast possi collections, dusting 382 00:25:23.119 --> 00:25:25.880 off their cold cases to see if they too might 383 00:25:25.920 --> 00:25:30.880 containing the Muzaban relics. Two archaic jawbones, one dug up 384 00:25:30.920 --> 00:25:34.240 west of Beijing, the other dredged from the Taiwan Strait 385 00:25:34.759 --> 00:25:38.359 our close physical matches with the mandible. If their identity 386 00:25:38.440 --> 00:25:41.680 is confirmed as expected, it will mean that the misavans 387 00:25:41.880 --> 00:25:46.720 ranged over all of mainland Asia, perhaps centering on what 388 00:25:46.839 --> 00:25:51.240 is now Chinese territory. Chinese researchers have begun to reshape 389 00:25:51.319 --> 00:25:55.680 long standing consumptions about what when we branched off from 390 00:25:55.680 --> 00:26:00.359 our fellow prominence. A recent phylogenetic study of one Chinese 391 00:26:00.400 --> 00:26:04.559 skull pushed back our divergence from Theangartals and Dinizebans by 392 00:26:04.640 --> 00:26:08.880 three hundred thousand years, shaking long held beliefs about whether 393 00:26:08.920 --> 00:26:13.039 our common ancestor even lived in Africa. Then there's the 394 00:26:13.119 --> 00:26:16.400 Harbin skull, found in nineteen thirty three by a worker 395 00:26:16.519 --> 00:26:19.480 in northeastern China and hidden in a well for the 396 00:26:19.519 --> 00:26:22.480 rest of the twentieth century. The one hundred forty six 397 00:26:22.559 --> 00:26:26.039 thousand year old fossil could belong to a hominym relative 398 00:26:26.160 --> 00:26:31.119 closer to modern humans than either Niagartals or Dinizibans, a 399 00:26:31.279 --> 00:26:34.920 tantalizing clue that inches us nearer to the identity of 400 00:26:34.960 --> 00:26:38.920 our common ancestor. Some scientists think the Harbin skull could 401 00:26:38.920 --> 00:26:42.200