0:00:01.024,0:00:02.754 Paleontology, 0:00:02.778,0:00:05.619 a science geared towards small children. 0:00:05.643,0:00:08.532 Focused on digging up dinosaurs 0:00:08.556,0:00:10.635 while sporting a "Jurassic Park" costume. 0:00:11.188,0:00:13.236 Skulls are popped out of the ground 0:00:13.260,0:00:15.736 and put on display for public gawking. 0:00:16.204,0:00:20.951 The relevance of this, beyond clickbait,[br]coloring books and monster movies, 0:00:20.975,0:00:22.125 is unknown. 0:00:22.792,0:00:23.942 No ... 0:00:24.357,0:00:25.507 Wait. 0:00:26.801,0:00:29.221 That's not paleontology at all. 0:00:29.815,0:00:33.965 Paleontology is nothing less[br]than the study of past life. 0:00:33.989,0:00:35.545 All past life. 0:00:35.569,0:00:38.264 From ancestors to alien forms. 0:00:38.693,0:00:42.336 It involves fundamental questions[br]like "who are we," 0:00:42.360,0:00:44.042 and "how did we get here," 0:00:44.066,0:00:46.736 using the broadest possible[br]definition of "we" -- 0:00:47.058,0:00:48.796 life itself. 0:00:49.714,0:00:52.769 Dinosaurs, a category of birds, 0:00:52.793,0:00:54.960 are just a small percentage of that. 0:00:54.984,0:00:56.182 (Laughter) 0:00:56.206,0:00:59.182 Yet they get the most media attention. 0:00:59.206,0:01:02.409 [The incredible diversity of ancient life,[br]Dinosaurs, Paleontology] 0:01:02.433,0:01:05.251 It's a very accurate meme;[br]I didn't even make this one. 0:01:05.275,0:01:06.886 This is just the truth. 0:01:06.910,0:01:12.590 Anyway, most of us paleontologists[br]consider dinosaurs to be a gateway drug. 0:01:12.919,0:01:15.855 There is so much cooler stuff[br]in the fossil record, 0:01:15.879,0:01:18.227 and we know so much about it. 0:01:18.251,0:01:21.244 Let's go on a brief, dinosaur-free tour 0:01:21.268,0:01:23.482 of the last four billion years. 0:01:23.506,0:01:24.783 (Laughter) 0:01:24.807,0:01:26.720 First up, genetic material. 0:01:26.744,0:01:29.886 Viruses, basically,[br]started producing proteins 0:01:29.910,0:01:32.102 and wrecking their environment. 0:01:32.514,0:01:35.243 The Earth was infected with life. 0:01:35.826,0:01:39.723 Some of these new bacteria[br]learned how to eat sunshine, 0:01:39.747,0:01:41.255 producing oxygen, 0:01:41.279,0:01:43.247 pulling carbon from the air, 0:01:43.271,0:01:47.075 and destroying the iron food[br]of other microbes, 0:01:47.099,0:01:48.764 by turning it into rust. 0:01:48.788,0:01:51.557 This went on for billions of years. 0:01:51.581,0:01:54.724 Some bacteria consumed other bacteria, 0:01:54.748,0:01:58.423 gaining their power[br]to turn oxygen into energy, 0:01:58.447,0:02:01.685 becoming the precursors[br]of animals and plants. 0:02:01.709,0:02:04.494 But as a result,[br]there were climate shocks, 0:02:04.518,0:02:07.005 from hot to cold and back again, 0:02:07.029,0:02:11.091 which ended up turning the Earth[br]into a snowball covered with glaciers. 0:02:11.538,0:02:14.834 The technical term for this time period[br]is "Snowball Earth." 0:02:15.434,0:02:18.283 (Laughter) 0:02:18.307,0:02:20.728 Seven hundred, eight hundred[br]million years ago. 0:02:20.752,0:02:23.337 Anyway, microbes banded together, 0:02:23.361,0:02:25.672 creating multicellular life. 0:02:25.696,0:02:27.617 Six hundred million years ago, 0:02:27.641,0:02:31.720 geometric colonies appeared,[br]sucking microbes from the water. 0:02:31.744,0:02:35.736 These were soon replaced[br]by the ancestors of modern animals. 0:02:36.077,0:02:38.442 The Cambrian explosion. 0:02:38.466,0:02:41.633 Lobster relatives ate other animals, 0:02:41.657,0:02:44.390 capturing them using their grasping arms. 0:02:44.749,0:02:49.455 Armored wriggling clam worms[br]crawled across the seafloor and into it, 0:02:49.479,0:02:51.518 creating new ecosystems. 0:02:52.097,0:02:56.403 Our tadpole-like ancestors[br]flitted along ancient coastlines, 0:02:56.427,0:02:59.998 while their eel-like relatives[br]with gnashing throat teeth 0:03:00.022,0:03:04.401 swam above the ice-cream cone corals[br]of the first reefs, 0:03:04.425,0:03:06.457 dodging school-bus-sized krakens 0:03:06.481,0:03:08.750 and hungry sea scorpions. 0:03:09.139,0:03:11.353 Plant fungus came onto land. 0:03:11.703,0:03:15.189 But then the glaciers returned,[br]killing pretty much everything. 0:03:15.641,0:03:18.380 But mass extinctions open opportunities. 0:03:18.404,0:03:20.800 Jawless fishes invaded the ocean, 0:03:20.824,0:03:24.522 sporting points, prongs,[br]and finally, fins. 0:03:24.546,0:03:29.172 Spiders, scorpions, snails[br]and worms came onto land. 0:03:29.649,0:03:33.117 Somewhere around China,[br]a fish developed jaws, 0:03:33.141,0:03:35.768 and its descendants drove jawless fishes, 0:03:35.792,0:03:37.895 sea scorpions and branching plankton 0:03:37.919,0:03:39.537 to extinction. 0:03:39.561,0:03:40.752 Some of these fishes, 0:03:40.776,0:03:42.672 which had arm bones in their fins, 0:03:42.696,0:03:44.141 sprouted fingers, 0:03:44.165,0:03:46.434 seven or eight per flipper. 0:03:47.007,0:03:49.252 On land, plants became trees, 0:03:49.276,0:03:50.656 growing massive 0:03:50.680,0:03:54.014 or spreading their spores[br]only once before dying. 0:03:54.617,0:03:56.958 But then the glaciers came back again 0:03:56.982,0:03:59.347 and it was mass extinction number two. 0:03:59.371,0:04:02.998 It was the age of weird fishes[br]and plated sea lilies. 0:04:03.022,0:04:04.680 Sharks with wings. 0:04:04.704,0:04:06.609 Sharks with buzz saw jaws. 0:04:06.633,0:04:09.299 Sharks with fins covered in tiny teeth. 0:04:09.323,0:04:11.489 Sharks with crushing tooth plates. 0:04:11.513,0:04:14.871 Bony fishes that looked like[br]modern angelfish and eels 0:04:14.895,0:04:16.274 for the first time. 0:04:16.649,0:04:18.014 Wetlands developed, 0:04:18.038,0:04:21.887 sporting ten-foot-long millipedes[br]and giant dragon flies. 0:04:21.911,0:04:25.474 These spread across the supercontinent[br]of Pangaea and died, 0:04:25.498,0:04:27.006 creating coal, 0:04:27.030,0:04:30.259 leading to a 100-million-year Ice Age. 0:04:30.716,0:04:35.002 Finally, vertebrates made it onto land[br]on a permanent basis, 0:04:35.026,0:04:37.359 leading to alligator-like amphibians 0:04:37.383,0:04:40.343 and saber-toothed protomammals. 0:04:40.367,0:04:44.047 But then, volcanoes erupted[br]all over Siberia, 0:04:44.071,0:04:45.251 everything almost died, 0:04:45.275,0:04:47.531 and it was mass extinction number three. 0:04:47.957,0:04:49.087 (Laughter) 0:04:49.111,0:04:50.778 The day life nearly died. 0:04:51.307,0:04:55.970 A single, lonely tusked mammal[br]survived and thrived, 0:04:56.434,0:04:59.591 but it was soon replaced[br]by galloping crocodiles. 0:04:59.615,0:05:02.353 In the ocean, marine reptiles, 0:05:02.377,0:05:06.551 giant rafts made of the living[br]relatives of sea urchins, 0:05:06.853,0:05:11.759 and armored squids, ammonoids[br]of every kind and form. 0:05:12.347,0:05:14.760 But then, Pangaea started to split apart, 0:05:14.784,0:05:16.481 forming a sea of lava 0:05:16.505,0:05:19.260 that would one day become[br]the Atlantic Ocean, 0:05:19.284,0:05:21.696 spewing toxic gas into the atmosphere 0:05:21.720,0:05:23.853 and mass extinction number four. 0:05:24.195,0:05:25.426 (Laughter) 0:05:25.450,0:05:27.798 Yeah, there's actually[br]a lot more than these five, 0:05:27.822,0:05:29.029 these are the big ones. 0:05:29.053,0:05:31.920 (Laughter) 0:05:32.662,0:05:36.790 So, finally, there were[br]whale-sized fishes, 0:05:36.814,0:05:38.877 and modern fishes mobbed corals, 0:05:38.901,0:05:44.245 made gigantic by using[br]their captured algae to eat sunshine. 0:05:44.269,0:05:48.697 Crabs, stingrays and other fishes[br]with crushing teeth appeared, 0:05:48.721,0:05:49.936 smashing shells 0:05:49.960,0:05:53.466 and leading to an arms race[br]between predators and prey. 0:05:53.490,0:05:56.449 There was an explosion[br]of marine biodiversity. 0:05:57.244,0:05:59.434 Mammals climbed trees, flew, 0:05:59.458,0:06:03.693 and did a lot of other things[br]that are seemingly sort of modern. 0:06:04.238,0:06:08.389 They were feeding on the first flowers[br]pollinated by the first bees. 0:06:08.413,0:06:12.214 There were ecological revolutions[br]on land and at sea, 0:06:12.238,0:06:14.105 leading to the modern world. 0:06:14.434,0:06:17.490 Except that an asteroid hit Mexico, 0:06:17.514,0:06:21.704 and then that triggered volcanoes[br]on the other side of the world in India, 0:06:21.728,0:06:24.100 and everything almost died again. 0:06:24.124,0:06:25.586 (Laughter) 0:06:25.610,0:06:30.014 But -- there's always a but,[br]because we're still here -- 0:06:30.038,0:06:32.419 mammals arose from the ashes, 0:06:32.443,0:06:36.212 became small under extreme heat,[br]and then ever larger. 0:06:36.236,0:06:38.966 There were palm trees[br]and snakes in the Arctic. 0:06:38.990,0:06:42.569 Predatory deer dogs frolicked[br]along ancient rivers, 0:06:42.593,0:06:45.048 while their relatives[br]returned to the ocean 0:06:45.072,0:06:48.246 to become the first otter-like whales. 0:06:48.270,0:06:51.730 Not hyenas and other sort of carnivores 0:06:51.754,0:06:54.839 were chased off by giant[br]long-necked rhinos. 0:06:54.863,0:06:57.672 Everything at this point[br]seems kind of familiar, 0:06:57.696,0:06:58.846 but not really. 0:06:59.268,0:07:02.545 In Antarctica, an ice age started, 0:07:02.569,0:07:06.799 forming the first permanent polar ice cap[br]in two hundred million years. 0:07:07.268,0:07:09.553 This dried out the rest of the world, 0:07:09.577,0:07:13.632 but it allowed the rise of grasses,[br]of rodents, of cats. 0:07:13.998,0:07:15.506 Somewhere in Africa, 0:07:15.530,0:07:18.091 an ape started walking[br]across the new savannah. 0:07:19.002,0:07:21.661 Oh, and there were giant[br]saber-toothed salmon, 0:07:21.685,0:07:23.153 I just have to mention that. 0:07:23.177,0:07:25.849 (Laughter) 0:07:26.225,0:07:29.307 So, we know all of this happened, 0:07:29.331,0:07:30.736 and so much more. 0:07:30.760,0:07:31.911 How? 0:07:31.935,0:07:33.141 Why? 0:07:33.165,0:07:35.816 Paleontology is a thriving science 0:07:35.840,0:07:40.374 at the intersection of multiple[br]other fields and technologies. 0:07:40.398,0:07:43.128 There is no bigger data[br]than the fossil record, 0:07:43.152,0:07:45.112 and we mine every bit of it. 0:07:45.136,0:07:46.429 We use CAT scans, 0:07:46.453,0:07:47.802 we use isotopes, 0:07:47.826,0:07:49.350 we use genomes, 0:07:49.374,0:07:50.696 we use robots, 0:07:50.720,0:07:52.783 we use mathematical simulations, 0:07:52.807,0:07:55.149 and all kinds of analytics. 0:07:55.173,0:07:58.970 We maximize all of it[br]so that we can understand the past, 0:07:58.994,0:08:00.594 and how evolution works. 0:08:01.049,0:08:04.049 It also lets us make[br]predictions for the future. 0:08:04.073,0:08:06.827 What will happen after the next[br]mass extinction? 0:08:06.851,0:08:08.918 What weird things will show up? 0:08:09.307,0:08:11.374 Will mammals get smaller again? 0:08:11.712,0:08:13.767 Will there even be mammals? 0:08:14.831,0:08:16.355 In sum, 0:08:16.379,0:08:19.831 we have learned a lot about dinosaurs. 0:08:20.236,0:08:21.838 But there's so much left to learn 0:08:21.862,0:08:26.013 from the other 99.9 percent of things[br]that have ever lived. 0:08:26.434,0:08:28.545 And that's paleontology. 0:08:28.990,0:08:30.188 Thank you. 0:08:30.212,0:08:35.219 (Applause and cheers)