1 00:00:01,880 --> 00:00:05,400 Speaker 1: Hey, welcome to Sign Stuff, a production of iHeartRadio. I'm 2 00:00:05,400 --> 00:00:09,160 Speaker 1: hoor hitchhim, and today we're answering the question did dinosaurs 3 00:00:09,560 --> 00:00:12,520 Speaker 1: have feathers? You might think you know the answer to 4 00:00:12,560 --> 00:00:15,720 Speaker 1: this question, but as we'll learn today, the real answer 5 00:00:15,960 --> 00:00:19,680 Speaker 1: has changed significantly in the last few years. To get 6 00:00:19,680 --> 00:00:21,720 Speaker 1: the full story, we're going to talk to a couple 7 00:00:21,760 --> 00:00:24,960 Speaker 1: of paleontologies. We're going to tell us what we know 8 00:00:25,239 --> 00:00:29,080 Speaker 1: about the origin of feathers, which dinosaurs had them, and 9 00:00:29,120 --> 00:00:32,879 Speaker 1: why feathers evolved in the first place. I promise by 10 00:00:32,920 --> 00:00:36,000 Speaker 1: the end you want to look at dinosaurs or feathers 11 00:00:36,360 --> 00:00:44,880 Speaker 1: the same way again. Enjoy. Hey everyone, So I picked 12 00:00:44,880 --> 00:00:47,920 Speaker 1: today's topic to celebrate the release of my news book, 13 00:00:48,280 --> 00:00:52,680 Speaker 1: Oliver's Great Big Universe Evolution Changes Everything. It's all about 14 00:00:52,680 --> 00:00:55,280 Speaker 1: the history of life on Earth, is told by a 15 00:00:55,360 --> 00:00:58,200 Speaker 1: kid named Oliver. It's a great book for those smart 16 00:00:58,280 --> 00:01:02,800 Speaker 1: kids in your life, your nieces or nephews, your friend's kids. 17 00:01:03,160 --> 00:01:05,720 Speaker 1: I promise, if they like funny stories and you think 18 00:01:05,760 --> 00:01:08,160 Speaker 1: they might like science, I think this might be their 19 00:01:08,280 --> 00:01:11,200 Speaker 1: favorite new book series. So please check it out at 20 00:01:11,240 --> 00:01:15,040 Speaker 1: Great Big Universe dot net or your favorite bookseller. All right, 21 00:01:15,160 --> 00:01:18,679 Speaker 1: let's talk about dinosaurs and feathers. Now, I'm excited for 22 00:01:18,720 --> 00:01:22,680 Speaker 1: today's episode because we're gonna hear from two paletologists, one 23 00:01:22,680 --> 00:01:26,320 Speaker 1: of whom was involved in the landmark discovery that put 24 00:01:26,360 --> 00:01:29,920 Speaker 1: the origin of feathers way further back in time than 25 00:01:30,040 --> 00:01:33,280 Speaker 1: anyone expected. But before we get there, I thought it 26 00:01:33,319 --> 00:01:36,440 Speaker 1: was important that we covered the basics first because that's 27 00:01:36,480 --> 00:01:38,840 Speaker 1: going to help us later in the episode. And the 28 00:01:38,840 --> 00:01:41,800 Speaker 1: first question we're going to ask is what exactly is 29 00:01:41,840 --> 00:01:45,720 Speaker 1: a dinosaur? You probably think you know, but according to 30 00:01:45,760 --> 00:01:52,040 Speaker 1: our first expert, the answer is not that simple. Well, 31 00:01:52,040 --> 00:01:54,000 Speaker 1: thank you, doctor O'Connor for joining us today. 32 00:01:54,200 --> 00:01:56,560 Speaker 2: It's absolutely my pleasure. I'm a big fan, so I'm 33 00:01:56,560 --> 00:01:57,400 Speaker 2: happy to be here. 34 00:01:57,600 --> 00:01:59,760 Speaker 1: Awesome. Can you please tell us who you are and 35 00:01:59,760 --> 00:02:00,160 Speaker 1: what you do. 36 00:02:00,480 --> 00:02:04,720 Speaker 2: My name is Jingme O'Connor, and I'm the associate curator 37 00:02:04,800 --> 00:02:08,200 Speaker 2: of Fossil Reptiles at the Field Museum of National Street 38 00:02:08,240 --> 00:02:11,280 Speaker 2: in Chicago. It's just a fancy complicated way of saying 39 00:02:11,320 --> 00:02:13,959 Speaker 2: that I'm a nerdy dinosaur paleontologist. 40 00:02:14,080 --> 00:02:16,680 Speaker 1: I guess maybe for people who are not super familiar. 41 00:02:16,960 --> 00:02:19,640 Speaker 1: He tell us what exactly is a dinosaur? Like what 42 00:02:19,760 --> 00:02:21,240 Speaker 1: makes a dinosaur a dinosaur. 43 00:02:21,520 --> 00:02:24,920 Speaker 2: Well, okay, that's not an easy question to answer. So 44 00:02:25,040 --> 00:02:29,040 Speaker 2: dinosaurs are basically a group of animals that have a 45 00:02:29,200 --> 00:02:33,079 Speaker 2: common ancestor. So, for example, all living mammals have one 46 00:02:33,120 --> 00:02:37,040 Speaker 2: common ancestor, that's why they form a true group. And 47 00:02:37,360 --> 00:02:40,560 Speaker 2: mammals are characterized by a specific set of traits that 48 00:02:40,600 --> 00:02:42,840 Speaker 2: you can then use to identify that they're mammals, like 49 00:02:42,919 --> 00:02:46,440 Speaker 2: milk and fur. But if only it was so easy 50 00:02:46,560 --> 00:02:51,600 Speaker 2: with dinosaurs. Unfortunately, dinosaurs are really weird and different, and 51 00:02:51,760 --> 00:02:54,840 Speaker 2: until recently we would have said things like dinosaurs have 52 00:02:54,880 --> 00:02:58,440 Speaker 2: a completely open hip socket and a bunch of traits 53 00:02:58,480 --> 00:03:01,800 Speaker 2: that for a long time really did define dinosaurs. But 54 00:03:01,880 --> 00:03:05,480 Speaker 2: then the more we find close relatives of dinosaurs, all 55 00:03:05,520 --> 00:03:08,960 Speaker 2: those traits we used to use suddenly got blurred. We 56 00:03:09,000 --> 00:03:12,680 Speaker 2: found that they were present in close non dinosaur animals, 57 00:03:12,840 --> 00:03:15,440 Speaker 2: or they were absent in the oldest known dinosaurs that 58 00:03:15,480 --> 00:03:16,360 Speaker 2: we started to find. 59 00:03:17,280 --> 00:03:20,080 Speaker 1: All Right, what doctor O'Connor is saying is that the 60 00:03:20,120 --> 00:03:23,800 Speaker 1: definition of a dinosaur is not an animal that looks 61 00:03:23,800 --> 00:03:27,720 Speaker 1: a certain way or as a certain characteristic. It just 62 00:03:27,760 --> 00:03:33,560 Speaker 1: means all the animals that came from one specific common ancestor. Because, 63 00:03:33,600 --> 00:03:38,600 Speaker 1: as it turns, out, dinosaurs have cousins. Not every big, 64 00:03:38,760 --> 00:03:43,120 Speaker 1: cool giant reptile is a dinosaur. For example, there are 65 00:03:43,160 --> 00:03:47,600 Speaker 1: the big reptiles that eventually became crocodiles. Crogs did not 66 00:03:47,680 --> 00:03:52,360 Speaker 1: come from dinosaurs. Or those giant swimming reptiles like Ichiosaurus 67 00:03:52,560 --> 00:03:55,880 Speaker 1: or plesiosaurs that you see swimming around in the Jurassic 68 00:03:55,920 --> 00:04:02,119 Speaker 1: Part movies. Those are not dinosaurs. There's a big one Terosaurus. 69 00:04:02,720 --> 00:04:06,000 Speaker 1: These are the giant flying reptiles that you also see 70 00:04:06,000 --> 00:04:11,080 Speaker 1: in movies, like pterodactyls or Terranodon. But the giant wings 71 00:04:11,160 --> 00:04:15,360 Speaker 1: and the long deaks dose are not dinosaurs either. They're 72 00:04:15,360 --> 00:04:19,080 Speaker 1: more like cousins of dinosaurs. So when you're talking about dinosaurs, 73 00:04:19,320 --> 00:04:23,320 Speaker 1: you're really talking about a specific family of animals that 74 00:04:23,440 --> 00:04:26,280 Speaker 1: came from one specific ancestor. 75 00:04:27,600 --> 00:04:31,480 Speaker 2: Let's just say that the ancestral dinosaur was probably a small, 76 00:04:31,720 --> 00:04:36,320 Speaker 2: warm blooded bipedal, probably carnivorous or omnivorous animal. 77 00:04:37,320 --> 00:04:41,279 Speaker 1: So scientists think the first dinosaur, the ancestor of the 78 00:04:41,360 --> 00:04:45,920 Speaker 1: animals we call dinosaurs, probably walked on two legs, kind 79 00:04:45,920 --> 00:04:49,440 Speaker 1: of like Terrannosaurus REGs or the veloscy raptors that again 80 00:04:49,880 --> 00:04:52,400 Speaker 1: you see in the Jurassic part movies. But here's a 81 00:04:52,440 --> 00:04:56,760 Speaker 1: confusing part. Some dinosaurs branched out and went back to 82 00:04:56,880 --> 00:04:59,560 Speaker 1: walking on four legs, and that's where you get some 83 00:04:59,600 --> 00:05:03,840 Speaker 1: of the they're famous dinosaurs like Triceratops or the one 84 00:05:03,839 --> 00:05:07,680 Speaker 1: with the really long neck, Brachiosaurus. All Right, I promise 85 00:05:07,760 --> 00:05:10,279 Speaker 1: this will all be useful later. Now let's get to 86 00:05:10,320 --> 00:05:14,000 Speaker 1: the other basic which is what exactly is a feather. 87 00:05:15,800 --> 00:05:19,320 Speaker 3: So my name is Maria McNamara and I am professor 88 00:05:19,360 --> 00:05:22,760 Speaker 3: of paleontology at University College Cork in Ireland. 89 00:05:23,080 --> 00:05:25,120 Speaker 1: Can you tell us what a feather is? 90 00:05:25,480 --> 00:05:29,000 Speaker 3: Ah, that's an interesting one. So a feather is basically 91 00:05:29,120 --> 00:05:33,360 Speaker 3: an integumentary appendage, to give it its scientific term. It's 92 00:05:33,400 --> 00:05:37,640 Speaker 3: basically made of protein, a protein called keratin. It's the 93 00:05:37,680 --> 00:05:41,159 Speaker 3: same protein that makes up our hair and nails, and 94 00:05:41,480 --> 00:05:46,040 Speaker 3: it is actually the most complex sort of tissue structure 95 00:05:46,360 --> 00:05:50,479 Speaker 3: that is known in vertebrate animals. Each feather has a 96 00:05:50,560 --> 00:05:56,280 Speaker 3: central sheaft with lateral side branches, and those branches have branches, 97 00:05:56,680 --> 00:06:01,280 Speaker 3: and actually the branches are organized in a spiral around 98 00:06:01,320 --> 00:06:05,080 Speaker 3: the shaft. So a feather is really the most complex 99 00:06:05,120 --> 00:06:06,640 Speaker 3: tissue structure that is known. 100 00:06:06,680 --> 00:06:10,360 Speaker 1: From the skin all right, you probably already knew what 101 00:06:10,440 --> 00:06:13,599 Speaker 1: a feather was. But here's the thing. That description of 102 00:06:13,640 --> 00:06:19,039 Speaker 1: feathers only applies to modern feathers. Early feathers, scientists think 103 00:06:19,400 --> 00:06:23,520 Speaker 1: we're a lot simpler. They look more like hairs, except 104 00:06:23,640 --> 00:06:27,640 Speaker 1: they're not hairs. How are they related to hairs? 105 00:06:28,480 --> 00:06:30,880 Speaker 3: What feathers and hair have in common is that they're 106 00:06:30,920 --> 00:06:34,280 Speaker 3: both outgroots from the skin, and they're both made of 107 00:06:34,360 --> 00:06:40,080 Speaker 3: keroten protein. But that's where the similarity ends because hairs, 108 00:06:40,360 --> 00:06:44,719 Speaker 3: unlike feathers, they don't branch, and hairs are solid. If 109 00:06:44,760 --> 00:06:47,000 Speaker 3: you slice through a hair and look at us onto 110 00:06:47,040 --> 00:06:52,200 Speaker 3: the microscope, you'll see a solid cylinder of keroten protein, 111 00:06:52,560 --> 00:06:55,520 Speaker 3: whereas if you slice through a feather, it's hollow in 112 00:06:55,560 --> 00:06:59,919 Speaker 3: the middle. So that's one major difference. And also in hairs, 113 00:07:00,120 --> 00:07:03,080 Speaker 3: we have a form of keratin called alpha keratin. Alpha 114 00:07:03,120 --> 00:07:07,720 Speaker 3: kerosin forms a helix, but the kerosion that's in feathers 115 00:07:08,040 --> 00:07:11,400 Speaker 3: has traditionally been called beta keratin, and that looks like 116 00:07:11,480 --> 00:07:14,840 Speaker 3: a corrugated tin roof, so it has an up and 117 00:07:14,880 --> 00:07:19,160 Speaker 3: down zigzag corrugated pattern. So the structure of the proteins 118 00:07:19,280 --> 00:07:20,120 Speaker 3: is very different. 119 00:07:20,600 --> 00:07:22,760 Speaker 1: It makes hair sound a lot more boring. 120 00:07:23,040 --> 00:07:27,600 Speaker 3: Hair is still a very interesting structure, but structurally it 121 00:07:27,640 --> 00:07:29,160 Speaker 3: is simpler than feathers. 122 00:07:29,760 --> 00:07:32,720 Speaker 1: So when we talk about dinosaurs, now you know what 123 00:07:32,720 --> 00:07:35,920 Speaker 1: we mean. And when we talk about feathers, you also 124 00:07:35,960 --> 00:07:37,800 Speaker 1: know what we mean. And now we get to the 125 00:07:37,880 --> 00:07:42,400 Speaker 1: question did dinosaurs have feathers? And I'll just tell you 126 00:07:42,440 --> 00:07:46,320 Speaker 1: the answer to this question is kind of shocking. At least, 127 00:07:46,400 --> 00:07:51,080 Speaker 1: it really took me by surprise. Where did feathers come from? 128 00:07:51,240 --> 00:07:55,160 Speaker 3: Ha? If I could answer that question, I would get 129 00:07:55,360 --> 00:07:57,800 Speaker 3: I don't know, a normal prize or something. 130 00:07:58,800 --> 00:08:00,600 Speaker 1: Yeah, that's good, let's get you noble price. 131 00:08:00,840 --> 00:08:03,320 Speaker 3: Yeah. Yeah, Well, look that question, where haven't you feathers 132 00:08:03,320 --> 00:08:06,640 Speaker 3: come from? That's the question that's been driving our research 133 00:08:07,120 --> 00:08:09,160 Speaker 3: over the last fifteen years. 134 00:08:10,000 --> 00:08:12,800 Speaker 1: All right. According to doctor McNamara, the answer to the 135 00:08:12,920 --> 00:08:16,760 Speaker 1: question did dinosaurs have feathers? Or where did feathers come from? 136 00:08:16,960 --> 00:08:20,800 Speaker 1: Has changed several times over the last thirty years, And 137 00:08:20,840 --> 00:08:24,600 Speaker 1: it's changed because we keep finding fossils that totally rewrite 138 00:08:24,720 --> 00:08:27,360 Speaker 1: what we think we know. So I'm going to take 139 00:08:27,400 --> 00:08:30,240 Speaker 1: you back starting in the nineteen nineties. 140 00:08:31,680 --> 00:08:34,040 Speaker 3: So you know, if we were to go back, let's 141 00:08:34,080 --> 00:08:36,839 Speaker 3: say to nineteen ninety, right, and if you would ask 142 00:08:36,920 --> 00:08:39,440 Speaker 3: me where the feathers come from, I would have told you, well, 143 00:08:39,520 --> 00:08:43,920 Speaker 3: that's easy. Birds evolved feathers. Feathers are a feature that 144 00:08:44,000 --> 00:08:45,200 Speaker 3: are unique to birds. 145 00:08:45,480 --> 00:08:46,320 Speaker 1: Why do you think that is? 146 00:08:46,520 --> 00:08:49,960 Speaker 3: Because before the nineties, you know, they were the only 147 00:08:50,240 --> 00:08:53,280 Speaker 3: modern animals for which we had feathers. We hadn't discovered 148 00:08:53,320 --> 00:08:56,200 Speaker 3: any fossils at that point that preserved feathers. 149 00:08:55,920 --> 00:08:59,000 Speaker 1: And so the idea is that when birds evolved, part 150 00:08:59,040 --> 00:09:02,320 Speaker 1: of what made them birds was that they developed feathers exactly. 151 00:09:02,440 --> 00:09:06,480 Speaker 3: We thought that feathers were one of the defining characteristics 152 00:09:06,480 --> 00:09:10,160 Speaker 3: of birds. And I mean, there's other features that define birds, 153 00:09:10,200 --> 00:09:14,920 Speaker 3: having a really enlarge, exaggerated sternum, to have big, huge 154 00:09:15,160 --> 00:09:19,560 Speaker 3: chest muscles for powering flight. Birds have special little bones 155 00:09:19,559 --> 00:09:22,240 Speaker 3: in the shoulder girdle, they have special shape of their 156 00:09:22,280 --> 00:09:26,880 Speaker 3: clavical These were all thought to be defining characteristics of birds, 157 00:09:27,080 --> 00:09:29,680 Speaker 3: and feathers were thought to be one of those features. 158 00:09:29,720 --> 00:09:34,960 Speaker 3: We simply hadn't found any fossils that had evidence of feathers. 159 00:09:34,920 --> 00:09:38,319 Speaker 1: So before the nineteen nineties, we just thought feathers were 160 00:09:38,640 --> 00:09:41,720 Speaker 1: a birth thing. Modern birds were the only animals we 161 00:09:41,760 --> 00:09:44,679 Speaker 1: had ever seen with feathers, so we thought birds were 162 00:09:44,679 --> 00:09:48,880 Speaker 1: the ones that evolved them. That basically feathers started with birds, 163 00:09:49,200 --> 00:09:52,640 Speaker 1: which was a totally reasonable thing to assume. But then 164 00:09:52,720 --> 00:09:55,160 Speaker 1: something happened in the mid nineteen nineties. 165 00:09:56,640 --> 00:09:59,199 Speaker 3: But then in the mid nineteen nineties, the world was 166 00:09:59,280 --> 00:10:03,320 Speaker 3: literally turned up side down with the dramatic discovery that 167 00:10:03,760 --> 00:10:06,360 Speaker 3: some dinosaurs also had feathers. 168 00:10:07,320 --> 00:10:12,920 Speaker 1: Yes, the nineties didn't just give us grunch rock. The 169 00:10:13,000 --> 00:10:16,840 Speaker 1: nineties gave us one of the most significant dinosaur discoveries 170 00:10:17,200 --> 00:10:20,760 Speaker 1: in history. We're gonna talk about this discovery and how 171 00:10:20,840 --> 00:10:25,679 Speaker 1: it and other discoveries changed when we think feathers evolved. 172 00:10:26,120 --> 00:10:38,080 Speaker 1: Stay with us. We'll be right back, and we're back Okay. 173 00:10:38,200 --> 00:10:41,559 Speaker 1: Before the nineteen nineties, we thought feathers were just a 174 00:10:41,600 --> 00:10:44,640 Speaker 1: bird thing, and the story everyone agreed to was that 175 00:10:44,760 --> 00:10:47,920 Speaker 1: birds were the ones that evolved feathers. But then in 176 00:10:47,960 --> 00:10:51,080 Speaker 1: the mid nineteen nineties there was a discovery that rocked 177 00:10:51,320 --> 00:10:53,280 Speaker 1: everything we thought was true. 178 00:10:55,120 --> 00:10:58,480 Speaker 3: So in the nineteen nineties there was the discovery of 179 00:10:58,800 --> 00:11:03,520 Speaker 3: dinosaurs preserved soft tissues from the early Cretaceous je Hall 180 00:11:03,640 --> 00:11:08,280 Speaker 3: biota of China, and the Jehall biota is now recognized 181 00:11:08,320 --> 00:11:12,439 Speaker 3: as one of the most important fossil localities in the world. 182 00:11:12,840 --> 00:11:16,360 Speaker 3: So these fossils are found in northeast China, and they 183 00:11:16,400 --> 00:11:21,479 Speaker 3: preserve lots of different types of animals, with everything from plants, insects, turtles, 184 00:11:21,679 --> 00:11:26,119 Speaker 3: some early mammals, and lots of dinosaurs. What was discovered 185 00:11:26,360 --> 00:11:30,840 Speaker 3: was a dinosaur called sinosrouptrics. So Sinus ruptrics is a 186 00:11:30,880 --> 00:11:35,840 Speaker 3: small little therapod dinosaur and it's only about thirty centimeters tall, 187 00:11:36,320 --> 00:11:41,160 Speaker 3: and it preserves dark organic matter, dark remains of its 188 00:11:41,240 --> 00:11:44,680 Speaker 3: soft tissues around the head, down the back of the neck, 189 00:11:44,760 --> 00:11:48,320 Speaker 3: along the body, and along the tail. And when the 190 00:11:48,640 --> 00:11:52,720 Speaker 3: Chinese research team looked at these fossils under the microscope, 191 00:11:52,960 --> 00:11:57,360 Speaker 3: they could say that that brown material it actually had structure, 192 00:11:57,760 --> 00:12:01,479 Speaker 3: and that structure was that it was posed of thousands 193 00:12:01,480 --> 00:12:05,959 Speaker 3: of tiny filaments, and the Chinese team surmised that these 194 00:12:06,120 --> 00:12:09,880 Speaker 3: filaments were in fact a very simple sort of feather. 195 00:12:10,960 --> 00:12:16,319 Speaker 1: Basically, researchers in China discovered a dinosaur with feathers. It's 196 00:12:16,320 --> 00:12:19,280 Speaker 1: a tiny dinosaur, only about a foot tall, and what 197 00:12:19,320 --> 00:12:21,840 Speaker 1: the fossil showed was that it had kind of a 198 00:12:22,000 --> 00:12:25,400 Speaker 1: mohawk running down its back and a fuzzy tail with 199 00:12:25,520 --> 00:12:29,360 Speaker 1: stripes that looks sort of like the tail of a raccoon. Now, 200 00:12:29,440 --> 00:12:32,360 Speaker 1: I know what you're thinking, that doesn't quite sound like feathers, 201 00:12:32,920 --> 00:12:36,080 Speaker 1: and that's why this fossil was a little controversial. 202 00:12:37,880 --> 00:12:42,319 Speaker 3: Now this proved massively controversial because you know, the feathers 203 00:12:42,360 --> 00:12:45,520 Speaker 3: that were all very familiar with, they have that clear 204 00:12:45,679 --> 00:12:48,199 Speaker 3: pattern of branching. They have the central shaft and the 205 00:12:48,280 --> 00:12:52,080 Speaker 3: lateral branches. But what not many people know is that 206 00:12:52,360 --> 00:12:56,640 Speaker 3: some birds do have feathers that have a very simple structure. 207 00:12:56,880 --> 00:13:01,480 Speaker 3: So some birds have feathers that are just simple filaments 208 00:13:01,520 --> 00:13:05,880 Speaker 3: that don't have any branching. So turkeys, for instance, they 209 00:13:05,920 --> 00:13:09,240 Speaker 3: have these weird, little spiky feathers that grow out of 210 00:13:09,280 --> 00:13:12,960 Speaker 3: their chin and they are bristles. They are just a 211 00:13:13,080 --> 00:13:16,599 Speaker 3: simple filament. And there's a bird called the black coucal, 212 00:13:17,320 --> 00:13:21,160 Speaker 3: and the black coucal the juveniles they have feathers that 213 00:13:21,240 --> 00:13:25,360 Speaker 3: don't branch. So there are modern examples of these sorts 214 00:13:25,360 --> 00:13:28,400 Speaker 3: of feathers, and so the Chinese team said, these are 215 00:13:28,640 --> 00:13:33,040 Speaker 3: so simple in structure, it's possible that these dinosaurs are 216 00:13:33,120 --> 00:13:37,640 Speaker 3: showing us some of the very earliest types of feathers. 217 00:13:38,720 --> 00:13:42,439 Speaker 1: Okay, so this wasn't a clear slam dug that dinosaurs 218 00:13:42,400 --> 00:13:48,439 Speaker 1: said feathers. People thought, well, they could be hairs. Well, 219 00:13:48,440 --> 00:13:50,040 Speaker 1: how do we know this are not just hairs. 220 00:13:50,240 --> 00:13:53,600 Speaker 3: Yeah, so that's a very good question, and to be honest, 221 00:13:53,880 --> 00:13:58,040 Speaker 3: that question wasn't answered for quite some time because really, 222 00:13:58,080 --> 00:13:59,680 Speaker 3: if you want to prove that they're not hairs, you 223 00:13:59,679 --> 00:14:02,760 Speaker 3: need to prove that they're hollow and not solid. So 224 00:14:02,920 --> 00:14:07,199 Speaker 3: for a long time those structures were really controversial because 225 00:14:07,360 --> 00:14:10,679 Speaker 3: the Chinese teams they weren't doing the sort of microscopic 226 00:14:10,800 --> 00:14:14,720 Speaker 3: analyzes that were necessary to prove that they were feathers. 227 00:14:14,800 --> 00:14:18,600 Speaker 3: And what was really exciting was when the dinosaur Microraptor 228 00:14:19,000 --> 00:14:23,000 Speaker 3: was discovered. So this is a feathered dinosaur that preserves 229 00:14:23,120 --> 00:14:27,080 Speaker 3: structures that are onlyquivocally feathers. You can't argue with them 230 00:14:27,360 --> 00:14:30,600 Speaker 3: because they have the shaft, they have the lateral branches, 231 00:14:30,760 --> 00:14:33,520 Speaker 3: and they even have the branches on the branches. They 232 00:14:33,600 --> 00:14:37,160 Speaker 3: have the barbs and the barbules, and so those are 233 00:14:37,200 --> 00:14:41,920 Speaker 3: effectively modern type feathers. They're identical to the feathers that 234 00:14:41,920 --> 00:14:45,720 Speaker 3: we see in modern birds. So once Microraptor was discovered, 235 00:14:45,880 --> 00:14:48,760 Speaker 3: when then there was no disputing the fact that at 236 00:14:48,840 --> 00:14:53,120 Speaker 3: least some dinosaurs had true modern type feathers. 237 00:14:54,200 --> 00:14:56,840 Speaker 1: All right, here's a little bit of context. We've known 238 00:14:56,880 --> 00:15:00,560 Speaker 1: for a while that birds evolved from dinosaurs. If you've 239 00:15:00,560 --> 00:15:03,480 Speaker 1: heard of archaep terics, if also the kind of looks 240 00:15:03,520 --> 00:15:06,920 Speaker 1: halfway between a dinosaur and a bird that was discovered 241 00:15:07,080 --> 00:15:10,520 Speaker 1: in eighteen sixty one. What the discoveries in China did 242 00:15:10,920 --> 00:15:15,120 Speaker 1: was pushed the origin of feathers back to before archaep 243 00:15:15,200 --> 00:15:18,760 Speaker 1: terics and into the kind of dinosaurs that directly evolved 244 00:15:19,080 --> 00:15:24,400 Speaker 1: into birds. These dinosaurs are called therapods. So after these discoveries, 245 00:15:24,720 --> 00:15:28,720 Speaker 1: people thought, wow, feathers didn't start with birds. They started 246 00:15:28,800 --> 00:15:33,160 Speaker 1: right before birds, in the dinosaurs that evolved into birds. 247 00:15:34,920 --> 00:15:38,720 Speaker 3: So then you know our concept of rock feathers were 248 00:15:38,760 --> 00:15:42,000 Speaker 3: and where they came from. We felt, well, maybe feathers 249 00:15:42,040 --> 00:15:46,400 Speaker 3: are something that evolved in birds and they're very close 250 00:15:46,560 --> 00:15:50,400 Speaker 3: dinosaur relatives, that they were something that evolved just in 251 00:15:50,480 --> 00:15:54,840 Speaker 3: the bird like dinosaurs the therapods, and that's what we 252 00:15:54,920 --> 00:15:57,320 Speaker 3: thought for pretty much twenty years. 253 00:15:57,920 --> 00:16:01,400 Speaker 1: So for twenty years that was the story. Did dinosaurs 254 00:16:01,400 --> 00:16:05,920 Speaker 1: of feathers? The answer was yes, a few dinosaurs, the 255 00:16:05,960 --> 00:16:09,600 Speaker 1: ones that directly evolved into birds, had them, and that's 256 00:16:09,600 --> 00:16:14,280 Speaker 1: when feathers started, but then that all changed in twenty thirteen. 257 00:16:15,880 --> 00:16:19,920 Speaker 3: But then in twenty thirteen, we discovered a completely different 258 00:16:19,920 --> 00:16:22,360 Speaker 3: type of dinosaur that's not related to the birds like 259 00:16:22,440 --> 00:16:24,760 Speaker 3: dinosaurs at all, and each had feathers. 260 00:16:25,480 --> 00:16:28,480 Speaker 1: Okay, let's get to the big twenty thirteen discovery. What 261 00:16:28,600 --> 00:16:33,240 Speaker 1: doctor McNamara and her colleagues found was another dinosaur with feathers, 262 00:16:33,400 --> 00:16:35,160 Speaker 1: but this one was different. 263 00:16:38,040 --> 00:16:41,880 Speaker 3: It's an Ornithiskian dinosaur, so in the same family as 264 00:16:42,400 --> 00:16:47,880 Speaker 3: viserah Thops and ankylosaurs, you know, these big, lumbering kind 265 00:16:47,920 --> 00:16:52,560 Speaker 3: of beasts. So we found a quart repeated dinosaur, a herbivore. 266 00:16:53,160 --> 00:16:55,760 Speaker 3: Each had feathers, and it didn't just have one type 267 00:16:55,760 --> 00:16:58,840 Speaker 3: of feathers, it had three types of feathers, So that 268 00:16:59,080 --> 00:17:00,560 Speaker 3: really rocked the world. 269 00:17:01,640 --> 00:17:05,639 Speaker 1: What they found was a dinosaur they called Colinda dromuse, 270 00:17:05,880 --> 00:17:09,280 Speaker 1: and it had hair like feathers on its head, chests, 271 00:17:09,320 --> 00:17:12,439 Speaker 1: and legs. And what's significant about this dinosaur is that 272 00:17:12,480 --> 00:17:15,960 Speaker 1: it's on a totally different branch of dinosaurs than the 273 00:17:16,040 --> 00:17:20,000 Speaker 1: dinosaurs that evolved into birds. This one is more related 274 00:17:20,040 --> 00:17:23,359 Speaker 1: to Triceratops, which is the big four legged dinosaur with 275 00:17:23,480 --> 00:17:27,120 Speaker 1: the three horns, and this means feathers were even older 276 00:17:27,160 --> 00:17:28,080 Speaker 1: than people. 277 00:17:27,840 --> 00:17:34,640 Speaker 3: Thought by finding feathers in a more primitive dinosaur. If 278 00:17:34,680 --> 00:17:37,800 Speaker 3: these two groups of dinosaurs had them, well, that kind 279 00:17:37,840 --> 00:17:42,120 Speaker 3: of implies that the genetic machinery for making feathers may 280 00:17:42,200 --> 00:17:46,960 Speaker 3: have actually evolved very early during dinosaur evolution, so that 281 00:17:47,080 --> 00:17:51,560 Speaker 3: these distantly related types of dinosaurs had the ability to 282 00:17:51,600 --> 00:17:52,720 Speaker 3: produce feathers. 283 00:17:53,119 --> 00:17:56,520 Speaker 1: What doctor McNamara is saying is that the fact two 284 00:17:56,560 --> 00:18:01,679 Speaker 1: distant dinosaur cousins had feathers implies that their ancestor also 285 00:18:01,720 --> 00:18:03,760 Speaker 1: had feathers. It's sort of like if you and your 286 00:18:03,800 --> 00:18:07,280 Speaker 1: cousin have the same gene, the gene probably didn't start 287 00:18:07,320 --> 00:18:10,320 Speaker 1: with you. You both probably got it from your common 288 00:18:10,400 --> 00:18:14,280 Speaker 1: grandmother or grandfather. This meant that feathers didn't start with 289 00:18:14,359 --> 00:18:17,840 Speaker 1: the dinosaurs that became birds. They go back even further. 290 00:18:19,440 --> 00:18:22,479 Speaker 3: There is also the option that maybe two groups of 291 00:18:22,520 --> 00:18:27,440 Speaker 3: dinosaurs evolved feathers independently, but we actually considered it much 292 00:18:27,480 --> 00:18:33,680 Speaker 3: more likely that this shared possession of feathers reflects common ancestry, 293 00:18:33,880 --> 00:18:37,080 Speaker 3: that they were present in the common ancestor. So that 294 00:18:37,240 --> 00:18:41,080 Speaker 3: was the stage of play for about six or seven years. 295 00:18:41,560 --> 00:18:45,399 Speaker 1: That's right. That story only lasted about six years. And 296 00:18:45,440 --> 00:18:49,000 Speaker 1: that's because in twenty nineteen, doctor McNamara and her colleagues 297 00:18:49,200 --> 00:18:53,359 Speaker 1: found another fossil that totally threw that story out the window. 298 00:18:54,640 --> 00:18:57,000 Speaker 1: When we come back, we'll talk about that discovery and 299 00:18:57,040 --> 00:19:01,720 Speaker 1: we'll hear from our experts why scientists thinks evolved. Stay 300 00:19:01,760 --> 00:19:15,879 Speaker 1: with us, you're listening to science stuff. Welcome back, all right. 301 00:19:15,960 --> 00:19:19,359 Speaker 1: We're telling the story of what we know about dinosaurs 302 00:19:19,400 --> 00:19:24,119 Speaker 1: and feathers. In twenty thirteen, palontologist doctor Maria McNamara was 303 00:19:24,200 --> 00:19:27,600 Speaker 1: part of a team that made a remarkable discovery. The 304 00:19:27,720 --> 00:19:31,040 Speaker 1: fund feathers is a distant cousin of the dinosaurs that 305 00:19:31,200 --> 00:19:34,919 Speaker 1: eventually evolved into birds. And this meant that feathers didn't 306 00:19:34,960 --> 00:19:38,560 Speaker 1: evolve with birds, nor did they evolve with the dinosaurs 307 00:19:38,560 --> 00:19:42,360 Speaker 1: that became birds. Other dinosaurs had them, which meant the 308 00:19:42,359 --> 00:19:46,800 Speaker 1: origin of feathers went back even further. But how far back, 309 00:19:47,080 --> 00:19:51,760 Speaker 1: which dinosaur ancestor was it that first evolved feathers. The answer, 310 00:19:51,880 --> 00:19:55,760 Speaker 1: it turned out, was even more surprising than anyone expected. 311 00:19:57,680 --> 00:20:01,440 Speaker 3: That was the stage of play for about six seven years, 312 00:20:01,880 --> 00:20:06,119 Speaker 3: and then in twenty nineteen we discovered feathers in a 313 00:20:06,240 --> 00:20:11,680 Speaker 3: completely different group of animal. We discovered feathers in pterosaurs. 314 00:20:12,760 --> 00:20:16,159 Speaker 1: That's right, Doctor McNamara and her colleagues found feathers in 315 00:20:16,280 --> 00:20:21,840 Speaker 1: animals that aren't even dinosaurs. They found feathers in pterosaurs. Now, 316 00:20:21,920 --> 00:20:23,520 Speaker 1: what are pterosaurs. 317 00:20:25,560 --> 00:20:29,440 Speaker 3: These are the giant flying reptiles, the cousins of dinosaurs 318 00:20:29,640 --> 00:20:33,760 Speaker 3: that roamed the skies during much of the Mesozoic. So 319 00:20:33,800 --> 00:20:38,440 Speaker 3: we found these little baby pterosaurs, these two juveniles from 320 00:20:38,520 --> 00:20:44,160 Speaker 3: China that literally had feathers covering their entire bodies, and 321 00:20:44,520 --> 00:20:47,800 Speaker 3: they had four different types of feathers. They had some 322 00:20:48,119 --> 00:20:51,280 Speaker 3: simple hair like feathers that we have found on lots 323 00:20:51,320 --> 00:20:54,680 Speaker 3: of dinosaurs and that are also present in modern birds, 324 00:20:54,920 --> 00:20:58,560 Speaker 3: and three types of branched feather feathers that branch at 325 00:20:58,560 --> 00:21:01,399 Speaker 3: the base, feathers that branch and shaffway along the shaft, 326 00:21:01,640 --> 00:21:04,280 Speaker 3: and even some feathers that branch at the tip. So 327 00:21:04,320 --> 00:21:07,200 Speaker 3: we find these in these juvenile terosaurs. 328 00:21:08,080 --> 00:21:11,440 Speaker 1: So they found feathers, real feathers in animals that are 329 00:21:11,480 --> 00:21:14,639 Speaker 1: not dinosaurs. They're more like the cousins the whole group 330 00:21:14,760 --> 00:21:18,600 Speaker 1: of dinosaurs. Now what does this mean, Well, there are 331 00:21:18,600 --> 00:21:23,920 Speaker 1: two possibilities. Either pterosaurs, the flying cousins of dinosaurs, also 332 00:21:24,000 --> 00:21:28,480 Speaker 1: evolved feathers, and the feathers look the same by sheer coincidents, 333 00:21:28,960 --> 00:21:32,320 Speaker 1: or feathers evolved way in the past before these two 334 00:21:32,359 --> 00:21:36,719 Speaker 1: groups of animals branched off. Now, the first possibility that 335 00:21:36,800 --> 00:21:39,720 Speaker 1: both groups of animals involved feathers and they look the 336 00:21:39,760 --> 00:21:44,400 Speaker 1: same by sheer coincidents does sometimes happen in nature. It's 337 00:21:44,400 --> 00:21:49,320 Speaker 1: called convergent evolution. For example, birds evolved wings, but so 338 00:21:49,480 --> 00:21:53,520 Speaker 1: that bats and sharks evolved fins and a streamlined body, 339 00:21:53,760 --> 00:21:56,400 Speaker 1: but so that whales. But in the case of feathers, 340 00:21:56,560 --> 00:22:01,400 Speaker 1: paleontologists argue this is very unlike likely. Here's how doctor 341 00:22:01,480 --> 00:22:03,280 Speaker 1: Jingme O'Connor explains it. 342 00:22:04,720 --> 00:22:08,280 Speaker 2: The one of the ways that paleontology makes hypotheses is 343 00:22:08,320 --> 00:22:10,920 Speaker 2: based on the principle of parsimony. 344 00:22:11,800 --> 00:22:17,199 Speaker 1: Okay, parsimony in general means being economical or cheap, but 345 00:22:17,400 --> 00:22:19,520 Speaker 1: in the context of science, it means that if you 346 00:22:19,560 --> 00:22:23,159 Speaker 1: have two possibilities, usually the one that's right is the 347 00:22:23,280 --> 00:22:26,879 Speaker 1: simpler one. If you've heard of Alkham's razor, it's pretty 348 00:22:26,960 --> 00:22:27,920 Speaker 1: much the same thing. 349 00:22:29,800 --> 00:22:34,840 Speaker 2: It's basically assuming that instead of evolution evolving these feathers 350 00:22:34,920 --> 00:22:38,480 Speaker 2: in pterosaurs and then also evolving them a different time 351 00:22:38,640 --> 00:22:42,480 Speaker 2: in dinosaurs. Since these groups are so closely related, it 352 00:22:42,520 --> 00:22:46,840 Speaker 2: would be most parsimonious that the common ancestor of these 353 00:22:46,880 --> 00:22:49,840 Speaker 2: two groups already had these features. And the reason it's 354 00:22:49,880 --> 00:22:53,440 Speaker 2: present in pterosaurs and dinosaurs is because they both inherited it. 355 00:22:54,000 --> 00:22:56,040 Speaker 1: What doctor O'Connor is saying is that it would be 356 00:22:56,080 --> 00:23:00,600 Speaker 1: a stretch for both dinosaurs and pterosaurs to evolve feathers 357 00:23:00,880 --> 00:23:04,720 Speaker 1: independently out of the blue, especially because a the two 358 00:23:04,760 --> 00:23:08,080 Speaker 1: groups of animals are closely related, so it's not a 359 00:23:08,119 --> 00:23:11,399 Speaker 1: stretch to imagine their common ancestor had feathers, and b 360 00:23:11,880 --> 00:23:16,240 Speaker 1: Feathers are complex, They're not easy to just suddenly evolve. 361 00:23:18,240 --> 00:23:24,119 Speaker 2: Feathers are complex structures, complex poratinous outgrowths. So the more 362 00:23:24,119 --> 00:23:27,680 Speaker 2: complex the structure is, like, the more unlikely it is 363 00:23:27,760 --> 00:23:31,439 Speaker 2: to evolve, you know, rather than having these complex like 364 00:23:31,560 --> 00:23:35,600 Speaker 2: caoratinous external structures evolving a bunch of different times and 365 00:23:35,720 --> 00:23:39,560 Speaker 2: all these dinosaurs and also in pterosaurs, it makes more sense, 366 00:23:39,760 --> 00:23:43,720 Speaker 2: or it's more parsimonious for it to evolve once in 367 00:23:43,760 --> 00:23:44,760 Speaker 2: the common ancestor. 368 00:23:45,440 --> 00:23:49,000 Speaker 1: And if you assume feathers evolved in a distant ancestor 369 00:23:49,080 --> 00:23:53,639 Speaker 1: of dinosaurs and pterosaurs, it means that feathers evolved before 370 00:23:54,200 --> 00:23:55,560 Speaker 1: dinosaurs existed. 371 00:23:57,240 --> 00:24:00,200 Speaker 3: We favor the idea that the presence of feather is 372 00:24:00,320 --> 00:24:04,960 Speaker 3: in terosaurs and dinosaurs. We feel that this implies that 373 00:24:05,040 --> 00:24:09,640 Speaker 3: the genetic networks required to grow feathers must have evolved 374 00:24:09,680 --> 00:24:13,480 Speaker 3: in the common ancestor of pterosaurs and dinosaurs, and that 375 00:24:13,600 --> 00:24:18,600 Speaker 3: common ancestor we predicted would have lived seventeen million years 376 00:24:18,800 --> 00:24:20,240 Speaker 3: earlier than both. 377 00:24:21,280 --> 00:24:24,520 Speaker 1: And this leads to the shocking answer I promised. If 378 00:24:24,560 --> 00:24:28,560 Speaker 1: feathers evolved before dinosaurs became their own branch of animals, 379 00:24:28,840 --> 00:24:32,800 Speaker 1: it means the ancestor of all dinosaurs had feathers, which 380 00:24:32,840 --> 00:24:37,200 Speaker 1: means all dinosaurs had feathers. It's not that a few 381 00:24:37,280 --> 00:24:41,120 Speaker 1: dinosaurs and feathers, or that some dinosaurs had them. They 382 00:24:41,280 --> 00:24:44,439 Speaker 1: all had feathers, or at least they all had the 383 00:24:44,560 --> 00:24:48,280 Speaker 1: genes the ability to grow feathers. We'll get to what 384 00:24:48,320 --> 00:24:50,880 Speaker 1: that means in a minute, but first it turns out 385 00:24:51,080 --> 00:24:55,520 Speaker 1: that's not the end of the story. 386 00:24:54,560 --> 00:24:57,280 Speaker 3: And that was the accepted state of play for the 387 00:24:57,400 --> 00:25:00,760 Speaker 3: last few years and most of the community. You know, 388 00:25:00,880 --> 00:25:03,800 Speaker 3: we're happy with the evidence that we put forward that 389 00:25:03,840 --> 00:25:08,280 Speaker 3: these structures were feathers, because we had evidence from microscopic analyzes. 390 00:25:08,480 --> 00:25:12,600 Speaker 3: We had evidence from chemical analyzes that they basically contained 391 00:25:12,680 --> 00:25:15,760 Speaker 3: the same sorts of pigment granules as feathers, and they 392 00:25:15,800 --> 00:25:18,480 Speaker 3: contained you know that we had chemical evidence for the 393 00:25:18,560 --> 00:25:22,000 Speaker 3: kerot and protein. But this year we produced really a 394 00:25:22,040 --> 00:25:23,520 Speaker 3: quite shocking discovery. 395 00:25:23,840 --> 00:25:26,199 Speaker 1: What another shocking discovery. 396 00:25:26,920 --> 00:25:30,240 Speaker 3: We were looking in some early Triassic rocks. We were 397 00:25:30,440 --> 00:25:35,840 Speaker 3: looking at animals that really they are very distant relatives 398 00:25:35,880 --> 00:25:39,800 Speaker 3: of dinosaurs and pterosaurs, and we found that some of 399 00:25:39,880 --> 00:25:46,600 Speaker 3: these very early Triassic reptiles, they preserve this remarkable structure 400 00:25:47,000 --> 00:25:51,160 Speaker 3: on their back that's made of these materials which look 401 00:25:51,560 --> 00:25:55,240 Speaker 3: so similar to feathers. They contained the same pigment granules 402 00:25:55,240 --> 00:25:59,400 Speaker 3: as feathers, but they lacked branching, so they don't fit 403 00:25:59,640 --> 00:26:04,040 Speaker 3: our kind of conventional idea of what a feather is, 404 00:26:04,080 --> 00:26:08,440 Speaker 3: So to be very conservative, we probably shouldn't call them feathers. 405 00:26:08,720 --> 00:26:12,840 Speaker 3: They do tell us that there were animals living in 406 00:26:12,880 --> 00:26:16,720 Speaker 3: the early Triassic that had structures that might have had 407 00:26:16,760 --> 00:26:18,800 Speaker 3: many of the same functions as feathers. 408 00:26:20,080 --> 00:26:24,040 Speaker 1: So just this year, in twenty twenty five, doctor McNamara 409 00:26:24,080 --> 00:26:27,959 Speaker 1: and her colleagues discovered proto feathers or prefeathers in an 410 00:26:28,000 --> 00:26:31,960 Speaker 1: animal that lived way before dinosaurs, which means it wasn't 411 00:26:32,000 --> 00:26:35,840 Speaker 1: just the ancestor of dinosaurs that had feathers, go even 412 00:26:35,920 --> 00:26:40,560 Speaker 1: further back. How far back scientists don't know. So here's 413 00:26:40,600 --> 00:26:44,399 Speaker 1: the working hypothesis. Feathers, or the genetic mutation that allows 414 00:26:44,400 --> 00:26:47,480 Speaker 1: an animal to grow these complex proteins into a structure 415 00:26:47,520 --> 00:26:52,080 Speaker 1: on their skin, evolved long before dinosaurs, and we see 416 00:26:52,080 --> 00:26:56,399 Speaker 1: feathers today in birds which descended from dinosaurs, which means 417 00:26:56,560 --> 00:27:00,800 Speaker 1: all dinosaurs probably had those genes. But does that mean 418 00:27:00,800 --> 00:27:04,119 Speaker 1: that t Rex or every dinosaur basically looked like a 419 00:27:04,200 --> 00:27:09,439 Speaker 1: giant chicken. Not really. Palatologists think all dinosaurs had the 420 00:27:09,520 --> 00:27:13,360 Speaker 1: capacity to grow feathers, but some didn't use it red 421 00:27:13,480 --> 00:27:16,720 Speaker 1: least once they got big, they didn't need it, which 422 00:27:16,840 --> 00:27:19,919 Speaker 1: brings us to the reason feathers might have evolved in 423 00:27:19,960 --> 00:27:22,560 Speaker 1: the first place, staying worn. 424 00:27:25,480 --> 00:27:29,800 Speaker 2: So it's very likely that large dinosaurs, if not completely 425 00:27:29,880 --> 00:27:33,720 Speaker 2: lost their feathering, like highly reduced it. And so that's 426 00:27:33,760 --> 00:27:36,919 Speaker 2: why I brought up the analogy with the elephant. I mean, 427 00:27:37,040 --> 00:27:39,840 Speaker 2: elephant is like a big mammal, so it has to 428 00:27:39,880 --> 00:27:41,919 Speaker 2: get rid of body heat. It also lives in a 429 00:27:41,960 --> 00:27:45,800 Speaker 2: really hot place, but it hasn't completely lost its fur. 430 00:27:46,200 --> 00:27:47,240 Speaker 1: It still has it. 431 00:27:47,240 --> 00:27:50,240 Speaker 2: It's just very sparse. So that's why I'm just making 432 00:27:50,240 --> 00:27:55,080 Speaker 2: the argument that maybe big dinosaurs would have highly reduced 433 00:27:55,119 --> 00:27:57,879 Speaker 2: their feathering, but would they completely lose it? 434 00:27:58,200 --> 00:27:58,679 Speaker 1: I don't know. 435 00:27:58,760 --> 00:28:01,440 Speaker 2: Like, I can't think of any mammal that has completely 436 00:28:01,480 --> 00:28:04,800 Speaker 2: lost its hair except for aquatic ones. I don't know 437 00:28:04,840 --> 00:28:08,200 Speaker 2: if like we have had some hair somewhere, whales or hair, 438 00:28:08,600 --> 00:28:09,399 Speaker 2: that'd be so funny. 439 00:28:09,600 --> 00:28:12,119 Speaker 1: I guess maybe a question is, what's the evolution of 440 00:28:12,160 --> 00:28:15,080 Speaker 1: those from proto feathers to the feathers we see, like 441 00:28:15,119 --> 00:28:18,320 Speaker 1: the beautiful feathers we see birds today. What was that progression? 442 00:28:18,680 --> 00:28:21,439 Speaker 2: So I just want to give a disclaimer that the 443 00:28:21,480 --> 00:28:26,000 Speaker 2: progression from proto feather to complex fractal feather, which we 444 00:28:26,080 --> 00:28:29,720 Speaker 2: call prenaceous feathers, it's highly hypothetical. 445 00:28:30,600 --> 00:28:33,520 Speaker 1: Gosh, we could spend a whole other episode just in this, 446 00:28:34,119 --> 00:28:38,120 Speaker 1: but here is the working hypothesis. Feathers likely evolved to 447 00:28:38,280 --> 00:28:41,840 Speaker 1: keep small animals warm, sort of like fur. You can 448 00:28:41,880 --> 00:28:45,240 Speaker 1: find this in animals dating bag to be four dinosaurs. 449 00:28:45,280 --> 00:28:48,760 Speaker 1: But then two things happened. Some dinosaurs started getting big, 450 00:28:48,960 --> 00:28:51,800 Speaker 1: and so they stopped needing this coat to stay warm, 451 00:28:51,960 --> 00:28:54,640 Speaker 1: which is why you only see baby pterosaurs covered in 452 00:28:54,640 --> 00:28:59,640 Speaker 1: feathers and why paleontologists think maybe baby t rexes had feathers, 453 00:28:59,760 --> 00:29:03,120 Speaker 1: but big adult ones didn't. They probably shed a lot 454 00:29:03,160 --> 00:29:06,880 Speaker 1: of it off, so no giant t rex chickens probably 455 00:29:07,280 --> 00:29:10,920 Speaker 1: And also evolution figured out feathers were also good for 456 00:29:11,160 --> 00:29:12,360 Speaker 1: other things. 457 00:29:13,600 --> 00:29:18,680 Speaker 2: So exactation is the fancy evolutionary biology word for evolution 458 00:29:19,080 --> 00:29:22,040 Speaker 2: taking a feature that has evolved for some other reason 459 00:29:22,240 --> 00:29:26,720 Speaker 2: and then hijacking it for another function. So sinoserapter its 460 00:29:26,800 --> 00:29:31,160 Speaker 2: fuzzy little dinosaur covered in proto feathers, but tail is striped. 461 00:29:31,640 --> 00:29:35,000 Speaker 2: These feathers are not just being used for thermal regulation. 462 00:29:35,360 --> 00:29:39,920 Speaker 2: They're also being co opted for communication, either within a 463 00:29:39,960 --> 00:29:42,560 Speaker 2: species like hey you know wag my tail. Hey you're 464 00:29:42,600 --> 00:29:45,520 Speaker 2: also sinoserapteris what's up? Or Hey, this is my territory, 465 00:29:45,560 --> 00:29:47,880 Speaker 2: go away, you know, like just some kind of display, 466 00:29:48,040 --> 00:29:50,320 Speaker 2: some kind of communication. We really can't say. 467 00:29:50,960 --> 00:29:53,880 Speaker 1: So that's why you see some dinosaurs with the fancy 468 00:29:53,960 --> 00:29:57,760 Speaker 1: complex feathers. They used it for mating or to intimidate 469 00:29:57,840 --> 00:30:00,840 Speaker 1: other dinosaurs, and then eventually the di dinosaurs that would 470 00:30:00,840 --> 00:30:04,760 Speaker 1: evolve in the words figured out, hey, these feathers are 471 00:30:04,840 --> 00:30:06,480 Speaker 1: also pretty good for flying. 472 00:30:08,400 --> 00:30:12,160 Speaker 2: So for example, feathers like the fancy, panacious feathers, they 473 00:30:12,240 --> 00:30:14,720 Speaker 2: evolve for some other purpose and we're exacted for flight. 474 00:30:14,960 --> 00:30:17,040 Speaker 1: Like I said, we could go on a whole tangent 475 00:30:17,240 --> 00:30:20,560 Speaker 1: about feathers. But to recap the main question of the episode, 476 00:30:20,840 --> 00:30:25,600 Speaker 1: did dinosaurs have feathers? The answer is yes, they all did, 477 00:30:26,160 --> 00:30:29,320 Speaker 1: and this is something we just recently found out. Does 478 00:30:29,400 --> 00:30:33,280 Speaker 1: that mean all dinosaurs looked like giant chickens? Not necessarily, 479 00:30:33,640 --> 00:30:36,280 Speaker 1: but it definitely means they're a lot fuzzier than we 480 00:30:36,360 --> 00:30:42,400 Speaker 1: thought before. All Right, close the episode, here's doctor McNamara. 481 00:30:42,560 --> 00:30:46,440 Speaker 3: So that's where we are. It opens up all sorts 482 00:30:46,440 --> 00:30:49,840 Speaker 3: of ideas about where did feathers evolve? You know, are 483 00:30:49,840 --> 00:30:52,520 Speaker 3: we going to find true feathers in the early Triassic? 484 00:30:53,080 --> 00:30:57,280 Speaker 3: If that's the question we're asking, Well, these new fossils 485 00:30:57,400 --> 00:31:00,320 Speaker 3: from the Triassic tell us that in order to find 486 00:31:00,320 --> 00:31:04,440 Speaker 3: the answers for feather origins, we need to look back 487 00:31:04,480 --> 00:31:08,160 Speaker 3: in even all the rocks before the Triassic, And to 488 00:31:08,200 --> 00:31:11,680 Speaker 3: be honest, that's somewhere where we never thought we were 489 00:31:11,720 --> 00:31:12,640 Speaker 3: going to have to go. 490 00:31:13,280 --> 00:31:17,720 Speaker 1: That is amazing. Last question I guess is what gets 491 00:31:17,720 --> 00:31:21,160 Speaker 1: you excited about finding the origin of feathers. 492 00:31:21,160 --> 00:31:25,080 Speaker 3: Because they are just one of the most complex tissue 493 00:31:25,080 --> 00:31:29,280 Speaker 3: structures that vertebrates have, and because there's so much kind 494 00:31:29,320 --> 00:31:32,360 Speaker 3: of required to produce them. I just really want to 495 00:31:32,400 --> 00:31:35,840 Speaker 3: know why did vertebrates start producing these, Why did they 496 00:31:35,880 --> 00:31:38,960 Speaker 3: give us an advantage? Why did they give our deep 497 00:31:39,000 --> 00:31:43,440 Speaker 3: deep ancestors an advantage. I'm just really intrigued by it. 498 00:31:43,840 --> 00:31:47,320 Speaker 3: What really was driving evolution once we come on to land, 499 00:31:47,640 --> 00:31:51,000 Speaker 3: What do we do in this new environment? What are 500 00:31:51,040 --> 00:31:54,200 Speaker 3: the major challenges? You know, these are just really big 501 00:31:54,240 --> 00:31:59,000 Speaker 3: evolutionary questions, and we have the opportunity with feathers actually 502 00:31:59,080 --> 00:32:02,320 Speaker 3: to address some of that. So I just think it's 503 00:32:02,360 --> 00:32:02,920 Speaker 3: really fun. 504 00:32:03,160 --> 00:32:05,640 Speaker 1: That's so wonderful. Well, I hope you do get a 505 00:32:05,640 --> 00:32:10,960 Speaker 1: Nobel Prize for the Professor McNamara, or at the very least, 506 00:32:10,960 --> 00:32:12,360 Speaker 1: I hope you get a feather in your cap. 507 00:32:12,560 --> 00:32:14,080 Speaker 3: Thank you, Thank you very much. 508 00:32:15,200 --> 00:32:17,720 Speaker 1: All right, Hey, be sure to check out my latest book, 509 00:32:17,800 --> 00:32:21,800 Speaker 1: Oliver's Great Big Universe Evolution Changes Everything. Look for it 510 00:32:21,840 --> 00:32:24,880 Speaker 1: in your favorite online or local bookstore, or go to 511 00:32:25,120 --> 00:32:28,600 Speaker 1: Great Big Universe dot Net to learn more. Thanks a lot, 512 00:32:29,240 --> 00:32:33,800 Speaker 1: See you next time you've been Listening to Science Stuff 513 00:32:34,040 --> 00:32:37,880 Speaker 1: production of iHeartRadio Britten and produced by me Or Hitcham, 514 00:32:38,440 --> 00:32:42,400 Speaker 1: edited by Rose Seguda, executive producer Jerry Rowland, and audio 515 00:32:42,400 --> 00:32:45,479 Speaker 1: engineer and mixer Kasey Peckram. You can follow me on 516 00:32:45,480 --> 00:32:48,720 Speaker 1: social media. Just search for PhD Comics and the name 517 00:32:48,760 --> 00:32:51,440 Speaker 1: of your favorite platform. Be sure to subscribe to sign 518 00:32:51,520 --> 00:32:54,720 Speaker 1: Stuff on the iHeartRadio app, Apple Podcasts, or wherever you 519 00:32:54,760 --> 00:32:57,880 Speaker 1: get your podcasts, and please tell your friends we'll be 520 00:32:57,920 --> 00:33:02,360 Speaker 1: back next Wednesday with another episode. Hey, if you're wondering 521 00:33:02,400 --> 00:33:05,800 Speaker 1: how feathers can survive the fossilization process, here's our first 522 00:33:05,840 --> 00:33:11,520 Speaker 1: ever appendix with doctor Magnamara's explanation. How do these feathers 523 00:33:11,640 --> 00:33:14,520 Speaker 1: get preserved as fossils? I thought only like bones got 524 00:33:14,520 --> 00:33:15,560 Speaker 1: preserved as fossils. 525 00:33:15,760 --> 00:33:18,800 Speaker 3: So yeah, ninety nine times out of one hundred, you're right. 526 00:33:19,320 --> 00:33:23,000 Speaker 3: And usually when animals die, bones are the only things 527 00:33:23,040 --> 00:33:27,360 Speaker 3: that end up getting preserved. But sometimes the soft tissues 528 00:33:27,400 --> 00:33:31,520 Speaker 3: of animals and plants they don't rot away completely. In 529 00:33:31,560 --> 00:33:35,080 Speaker 3: the case of feathers, they're made of those proteins. They're 530 00:33:35,080 --> 00:33:40,760 Speaker 3: pretty tough, they're pretty robust, and they actually undergo transformations 531 00:33:41,000 --> 00:33:44,480 Speaker 3: when the rocks are buried and the molecules start to 532 00:33:45,040 --> 00:33:50,000 Speaker 3: link together. They form large polymers, and it turns out 533 00:33:50,000 --> 00:33:54,120 Speaker 3: that it's really hard for bacteria to destroy those polymers, 534 00:33:54,360 --> 00:33:57,880 Speaker 3: so once they start to polymerize, it actually enhances their 535 00:33:57,880 --> 00:33:59,000 Speaker 3: preservation potential. 536 00:33:59,120 --> 00:34:02,560 Speaker 1: So some of these proteins actually survived the fossilization products 537 00:34:02,560 --> 00:34:03,680 Speaker 1: like you can see them in the rock. 538 00:34:03,800 --> 00:34:08,000 Speaker 3: We can actually track the three dimensional architecture of the protein. 539 00:34:08,320 --> 00:34:12,160 Speaker 3: That's what's really distinctive about feather proteins is that three 540 00:34:12,200 --> 00:34:17,400 Speaker 3: dimensional corrugated shape rather than the helical shape. So we 541 00:34:17,480 --> 00:34:20,320 Speaker 3: know for a fact that some of the earliest birds 542 00:34:20,360 --> 00:34:23,919 Speaker 3: and feather dinosaurs their feathers were made of the same 543 00:34:24,000 --> 00:34:26,600 Speaker 3: proteins as the feathers of modern birds.