Story of Birds (featuring Dr. Steve Brusatte)

25:57Like, I think most people think of dinosaurs as like big reptiles that lived hundreds of millions of years ago, In which case, pterodactyls are in that category, even if they're not in the technical definition that you gave. Sort of the way that, like, you know, astronomers differentiate between, like, meteors and asteroids. But, like, normal people are like, I don't care if streaking across the sky, that's what I mean. Yeah, yeah, that is true. And there's other giant reptiles that lived during the age of dinosaurs, the Triassic, Jurassic, and Cretaceous periods, that also were not dinosaurs.

26:26There were a whole bunch of different giant reptiles that lived in the water. Plesiosaurs, Ectheosaurs, Mosasaurs. I'm just ticking off the names because I know we want as many Latin names as possible to keep our listeners interested. Wow. Wow. Thank you for that. But the fact is that, yeah, there were plenty of giant reptiles during the age of dinosaurs. Dinosaurs proper are only one group of those reptiles. And there is this more vernacular use of the word dinosaur, which is fine. I'm not going to scream at people the way that my son does if they misuse the term, if they're acting in good faith.

27:04But the important thing for our story, though, is that pterodactyls are not birds. They are two very different groups. It's not that today's birds evolved from the pterodactyls or anything like that. Actually, pterodactyls took to the skies first. And pterodactyls were the first group of animals with bones ever in the history of the Earth to evolve powered flapping flight. And by that, I mean wings that they could actively flap that would provide the lift and thrust needed to get airborne and move through the air. There's plenty of animals that can glide, that can soar. Talking about flying squirrels and flying fish and these kind of things.

27:41but is only pterodactyls and then birds and then bats, those three groups that have evolved powered flapping flight among animals with bones. The pterodactyls did it long before birds. Hold on. You said animals with bones so that you could like exclude some specific group, like what, insects or who else? Yeah, so I can exclude all the millions of insects and just consider them inconsequential. Wow. It's a trick. It's a, you know, a political trick I'm playing here. I'm glad you noticed that. Thank you. All of our beetle listeners are really offended. Yeah. Yeah. There's plenty of other animals, lots of insects that have evolved powered flapping flight in their own ways.

28:18That's true. Let's take a break. When we get back, Steve is going to tell us how the vertebrates, because who cares about the invertebrates, how the vertebrates went about doing this. Invertebrates have Latin names, too. Okay.

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31:20And we're back. Steve is telling us about how the pterosaurs were the first to be able to actually fly. And he's going to tell us how they did that. So the first pterodactyls took to the skies in the middle part of the Triassic period, back when all the land was gathered together as Pangea, the supercontinent, the single giant slab of land. And this was the same time the first dinosaurs were evolving on that land. And so that meant that pterodactyls, they went airborne probably about 80 million years before the first birds did. So they were the pioneers, which also means they were there when the first birds evolved.

32:03The pterodactyls were the incumbents. And so really, when the first birds evolved, they were interlopers in a pterodactyl world. And they were insurgents. And it's not that they just took over the skies instantaneously. No, it actually took many, many millions of years for birds to gradually diversify and spread around the world and evolve into new species and start to push out the pterosaurs. And it was really a long evolutionary war of attrition. And by the end of the Cretaceous, a good, you know, almost 100 million years after the first birds evolved, there were still birds and pterosaurs living together, but things had changed.

32:46The very oldest true bird we have in the fossil record is Archaeopteryx from Germany. This is this famous, iconic fossil, half dinosaur, half bird. It has feathers and wings and a wishbone, just like a bird, but it has teeth in its jaws. It has big, sharp claws on his hands. It has a long tail, just like a raptor dinosaur. This is the most beautiful, perfect transitional fossil you can imagine. Evolution captured in action like a freeze frame. And when Archaeopteryx and its close relatives, the first true birds, took to the skies about 150 million years ago, they had to welcome themselves into this world of pterosaurs.

33:27And Archaeopteryx is a famous fossil, very famous, only known from southern Germany. It's been known for about 160 years. There are only about 14 or 15 skeletons that have ever been found. But in the same rocks, there are thousands of pterodactyl skeletons that have been found. That goes to show you how thoroughly embedded the pterodactyls were in the skies when the first birds evolved. But if you fast forward to the end of the Cretaceous, the next interval of time, the age of T. rex and Triceratops, You still have birds and pterosaurs, but now there's all kinds of birds, including primitive ones that still had teeth and tails and claws, but also very advanced ones that had beaks and that had big chest muscles that they could flap their wings with for long periods of time and hollow bones and fast growth and warm-blooded metabolism and so on.

34:18and there were many more birds than pterodactyls. And then that world was rudely interrupted by the asteroid, and that's what ended up properly killing off the pterodactyls. It wasn't birds out-competing them or pushing them aside. The asteroid is what got rid of the pterodactyls. And if the asteroid never hit, maybe there would still be birds and pterodactyls living together today. So I want to hear more about why the asteroid killed the pterodactyls and not the birds. But you said something fascinating. You said half bird, half dinosaur. But birds are dinosaurs, right? So what makes something a bird?

34:51What are the quintessential birdy features? What would your six-year-old complain about? Great question. So when I was writing the story of birds, when I was writing the book, I often had Anthony's voice in the back of my head saying, make sure I explain this so I don't get the, yeah, but what about this question? And I was reading it to him. So when I say Archaeopteryx is half bird, half dinosaur, what I really mean is that it has advanced features of modern birds, Things that it used to fly, like its feathers and wings. But it also had a lot of features of the raptor dinosaur ancestors of birds, like the teeth and the sharp claws and the long tail.

35:27So that raises the question, then, what makes a bird a bird? And look, I don't think anybody out there, not to offend anybody, maybe there's a few of you, but most people listening to this probably do not want a long, tortured discussion of names and nomenclature and how we label stuff and how one scientist thinks this, but another scientist has an alternative naming system. But when it comes down to it, bird is a vernacular term. It's not a formal scientific term. There are plenty of formal scientific names, avies and aviali and neornithes and these groups on the tree of light that have formal scientific definitions.

36:05But when it comes down to it, most scientists, not all, because we do use words differently, even those of us who specialize in studying these things. But most scientists, definitely most paleontologists would say, we're going to start calling something a bird if it can do that most bird-like thing. And that is if it had wings that were big enough and that could move in the right way, that it could flap those wings and it could support itself in the air. It could generate lift and thrust. Archaeopteryx is the first fossil that we have in the fossil record that can do that. It had big enough wings that it could power its bodies through the air.

36:43And that's really a matter of physics. But can't pterodactyls do that also? Yeah, pterodactyls could, but they evolved totally separately from a totally different group, the same way bats did. Right. So, and their wings are very different. We know that because the wings of pterodactyls are nothing like the wing of a bird. A wing of a bird is an arm, a heavily modified arm. You have the normal arm bones, but the hand is all fused up. And the hand and the arm bones support an airfoil of feathers. of quill pen feathers. A pterodactyl wing is a single long finger, the fourth finger, the ring finger, that anchored a giant cell of skin.

37:19Crazy. Totally different. Now bats do something even more different. Their entire hand is expanded and anchors a skin membrane. So because the wings of the three groups are so different, that's how we know that they evolved differently. But to circle back to Archaeopteryx, it's the first fossil, the oldest one we know of, that had wings made of feathers that were big enough that it could flap them and keep itself up into the air. There were plenty of raptor dinosaurs that also had wings made of feathers, but they were small, too small. Which really means that wings must have evolved for something other than flying, which is a trippy thing to think about, of course, because we think, what do wings do in a bird?

37:57Birds use wings to fly, just like an airplane uses wings to fly. But that doesn't mean wings evolved for that purpose, because birds use wings for many other things, too. They use wings to protect their eggs in the nest. They use wings to keep themselves warm, like a coat. They use wings to display, to attract mates, to intimidate rivals. And so we actually think that the first wings in dinosaurs probably evolved as display structures, made up of these feathers that had originally evolved as integument, as a coat, a coat of little hairy bristles to keep these dinosaurs warm. And then some of those dinosaurs modified those simple feathers into wings made of quill pens, but those first wings were quite small, used for display.

38:46And then only later on were some of those display wings co-opted to form an airfoil. So in that way, the origin of flight in dinosaurs really was an accident. And that's true really of all evolution when you think about it. There's no grand plan about any of this. But something as profound as flight, such a new, powerful, revolutionary behavior, it just kind of developed when it could. Because you had these small dinosaurs that their bodies had gotten small for who knows why. Maybe just to hide more easily or because of their metabolism or whatever. Those bodies had feathers on them to stay warm.

39:25Some of those feathers were elaborated into display billboards to attract mates and intimidate rivals. And at some point, if those billboards became big enough relative to the size of the body, just by the laws of physics, if those dinosaurs were moving them around a little bit, they'd generate a bit of lift, a bit of thrust. And that's when natural selection could take over and modify those wings into ever better airfoils. And that's really probably how flight developed. and things like feathers and wings, they did not evolve for flying. There was no grand plan there, but they came together to form a flying machine.

39:59And the way I like to think about it is when we think about airplanes and aircraft that humans have invented. Okay, the Wright brothers, they made the first airplane that could fly, but they didn't invent the propeller. They didn't invent the wheel. They didn't invent the wing. They took these components and put them together in a new way, and evolution does the same thing. And with dinosaurs and birds, you had all this evolution of dinosaurs, and what emerged from that was this peculiar group of small, feathery winged dinosaurs that could flutter about in the air, and that is the origin story of birds.

40:32I love understanding how these things come together and why the transitionary pieces of it exist for other reasons. Super fascinating. I also want to understand a little bit more sort of the story in your mind of how flight itself began. Like, I get that you have these proto-wings which you develop for other reasons, but it's not like some Tuesday afternoon, a dinosaur was like, oh, if I do this, wow, now I'm soaring through the skies, right? Is it like a little hopping and a little gliding, which then gives them some benefit and then they get better and better at that and it's stronger and stronger?

41:03It's a great question. And I will be direct and upfront and say, we don't know the answer to that. We have some different theories, some different ideas. But ultimately, this was something that happened over 150 million years ago. We weren't around to see it. What we do know is that feathers first evolved as very simple little hair-like structures. So they could not have evolved for flying because, I mean, we can't use our hair to fly. So these dinosaurs couldn't have either. We also know that the first wings were too small to be used for flying just by the laws of physics. And so wings must not have evolved for flying either.

41:40So those are things that we do know with quite a lot of confidence from the fossil record. What we don't really know is the exact setting, the exact situation where these feathery winged dinosaurs started to move those wings in a way that they could get lift and thrust. Was it that they were running quickly on the ground and they were using those wings to maneuver and to turn and to break and they started to get a little bit of lift and started to defy gravity? Or could it have been they were living in the trees and they were jumping between branches and they were using those wings as a parachute to manipulate gravity?

42:19Or could it have been something totally different? I mean, some birds use their wings to swim. Who's to say some dinosaur with little wings wasn't using them as paddles in the water and that generated some pressure from natural selection? I mean, we don't know for sure. And I think we have to be humble in the face of the fossil record that when it comes to exactly knowing how certain behaviors originated, oftentimes we're not going to know. But we know the components. We know the general story. The general story is that things like feathers and wings, which birds need to fly today, they did not evolve for that purpose.

42:52They evolved for something else initially, and they were later repurposed by evolution. And that's, I think, the best we can really do at this point. Now, of course, we always need more fossils. And if we ever can confidently find fossils of those very first dinosaurs that we're moving about in the air, that would tell us more. You know, where those fossils are from. Were they animals living on the ground or do they come from a forest and they were in the tree? You could start to narrow it down if you had a perfect fossil record. But we're far from that. That's why we're always looking for more fossils.

43:24In the last year, there have been some really exciting new discoveries in China of fossil birds, basically the same age as Archaeopteryx, about 150 million years old in the Jurassic period, but they're quite different from Archaeopteryx. So there are new fossils out there that are emerging as we speak that are not challenging the overall story that birds evolved from dinosaurs or that feathers and wings evolved for other reasons before flight, but are helping to refine those hypotheses that we have about exactly how flight evolved. So there's a lot of exciting work still to come as all of these different farmers in China and young students and scientists in China are going out finding fossils and studying these new fossils.

44:04I don't want to get us too far off track from getting back to the like, how did the birds survive the asteroid? Oh, that's right. That's what we were going to talk about. But I was so excited when reading your book that we actually know what color some of these feathers were, not just on birds, but on like, you know, earlier dinosaurs. Can you tell us a bit, like, how do we know what color they were when we actually can't see the color in the fossils? It sounds impossible, doesn't it? It really does. And I remember when I was in school in the late 80s and early 90s, you know, growing up and out of Illinois, middle of farm country, my charming little hometown.

44:40I remember learning in school these lessons on dinosaurs. And we would be told things like in the books, you know, that there's some things about dinosaurs we'll never know. We'll never know what colors they were. Were they green? Were they brown? Were they purple and pink polka dot? And we just won't know because color doesn't preserve its fossils. Well, the most dangerous thing you can ever say is that we will never know, especially to a scientist. And so I try to never say that because you don't know what you're going to find. And what happened was about 20 years ago, there was a student, a really remarkable student, Jakob Winther's his name.

45:16He's now on the faculty in Bristol, but he was a student at the time. And he was studying this fossil squid. And he noticed that near this fossil squid was this patch of really dark black stuff. And he said, you know, the obvious thing. Is this stuff ink? Is it ink? I mean, you know, it makes total sense. And maybe if it was the senior professor looking at that, maybe they would have been embarrassed to say. But he was a student, you know, completely open mind, completely uninhibited. Is it ink? Fossilized ink. And so how could he tell? Well, he looked under the microscope, high-powered microscopes, and whoa, lo and behold, it looked just like modern squid ink when he looked under the microscope.

45:55Because it had these little bubbles inside, these things called melanosomes, which hold pigment. and you can tell different colors are formed by different types of melanosomes of different size and shapes. Not all colors, but colors like black and brown and gray and ginger and some of the iridescent shiny colors. And so he realized that in some cases you can get these little pigment vessels preserved for tens of millions of years as fossils, which then led him and others to say, well, wait a minute, if we can see this in a squid, what about some of these dinosaurs with feathers that are coming out of China.

46:28Let's look at these under the microscope. And lo and behold, there were melanosomes in the feathers, not in every feather, but in the best preserved ones. And they could map those melanosomes, the size and the shape of them, to known colors, because this is all just physics. It's optical physics. And so, okay, this feather has melanosomes in it that the size and shape of ones that we know give a brown color in modern birds, or they give a ginger color. And so from there, they were able to start to tell the color palettes of some of these dinosaurs. And what that does tell us is that some of these dinosaurs with feathers, they were not birds yet.

47:06They were not, they didn't have big wings. They weren't flapping those wings. They couldn't fly, but they had quite elaborate feathers. Feathers that were very colorful, really ostentatious patterns to them. Almost certainly, they must have been using these for display to attract mates, to intimidate rivals. though same way that so many modern birds do with their feathers. So it was this realization that helped build this hypothesis that wings first evolved for display and were later co-opted as airfoils for flying. We don't know again for sure that's exactly what happened, but the fact that you have small wings in these dinosaurs, too small to fly, and those wings have these really gaudy color patterns to them, it just makes sense that they were using them for display.

47:51And I think this is incredibly exciting. It's so cool. It's so neat, isn't it? This is science. It's wonderful when physics comes to the rescue, right? Physics came to the rescue. Oh, you were waiting for that, Daniel. Oh, my goodness. Physics came to the rescue. And it's not the first time in paleontology physics has come to the rescue, I must say. It happens in every story. Oh, don't. But just to be clear, we're not seeing the colors in the fossils, right? We're seeing traces of different shaped mechanisms that produce those colors. So it's one step indirect. In most cases, that's true. But occasionally, sometimes there's so many melanosomes that are so well preserved, probably because the feather was buried really quickly, that you actually see bands of color in those feathers.

48:34They wouldn't be exactly like in the living bird, but they are there, visible to the naked eye, these bands of different colors, which is just fascinating. Just incredible. I love that you call it ostentatious. Like if you got into a time machine and went back and saw the first birds, you'd be like, I'm sorry, that's a bit much, isn't it? Tone it down a little. It would be, it's like Liberace, you know, John's show from the 70s. Like, that's how I imagine these things. Just full on, just total, total full on, just going for it. Just visual display, boom, in your face, trying to get noticed, trying to show how attractive they are or how scary they are to their rivals.

49:14That was probably what drove much of the evolution of birds initially. So you're saying that birds through their whole history have been absolutely fabulous. They have been, and they remain absolutely fabulous. Absolutely. All right, we are going to take a break, and when we get back, y 'all are going to be so proud of us because we are actually going to answer the question we set out to answer like 15 minutes ago. What determined who survived the giant Cretaceous asteroid?

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52:31We are back. And 66 million years ago, a giant asteroid struck the Earth during the Cretaceous. We had pterosaurs. We had dinosaurs. We had birds, which we've learned are also dinosaurs, but are maybe not what we first think about when we hear the word dinosaur. Steve, who survived and why? Or first, actually, what was it like when that giant asteroid struck the Earth? Hell. It was like hell. Total hell on Earth. And with no hyperbole. I mean it. It was probably the single worst day in the history of Earth. This was not a normal day. This would have started like any normal day. And then all of a sudden, out of nowhere, out of the outer reaches of space, came this six-mile-wide rock.

53:14Just fell out of the sky. And the animals that were living then had no idea it was coming. They had no way to monitor the motions of the heavens. You know, I've read some reconstructions of this asteroid. And there's some that suggest that it did two passes. Like it made a near miss of the Earth. and went around the back of the sun and then came back and hit the earth. So if dinosaurs had done their astronomy, they would have had some warning. Okay, but Daniel. Fund science. That's the lesson. Fund your scientists. So hopefully we've learned our lesson there. And hopefully the next time an asteroid confronts us, it does a double pass just to show us it's there.

53:52But imagine, though, so T-Rex was there the day this happened. Triceratops was there. There were giant duck-filled dinosaurs and long-necked dinosaurs and all kinds of dinosaurs there. We know that from the fossil record. We have fossils of these dinosaurs going right up to the layer in the rock that is marked by all the chaos of the asteroid. And just imagine, your kind, your dinosaur family has been dominating the world for over 150 million years. You've been at the top of the food chain, different species in different places. but top of the food chain, the biggest meat eaters, the biggest plant eaters, all kinds of diversity.

54:29And then all of a sudden, this rock falls out of the sky. This thing is traveling, you know, well more than 10 times faster than a speeding bullet, probably much faster, as the physicists here could tell me. And when it hit the Earth, it released more than a billion nuclear bombs worth of energy. It punched a hole in the face of the Earth over 100 miles wide. And that's the crater that we can still see part of in Mexico. Most of it's covered by the Gulf of Mexico, by the water. But some of it does lap onto the land in the Yucatan near Cancun. This was catastrophic. This was the biggest asteroid that's hit the Earth in at least the last half a billion years.

55:10This was not a normal visitor from space. And the energy it released was so profound that it triggered earthquakes and wildfires and tsunamis. And you had all this destruction in the minutes and the hours after the asteroid. And a huge number of animals would have died if you were outside and exposed to the fires and to the scalding rain of all the stuff that was liquidized by the collision that then fell back down as these scalding glass bullets. And then there was acid rain that came down a little bit afterwards. And this was a disaster movie. This was, I mean, the weirdest, worst, kitschiest disaster movie you've ever seen.

55:51Even worse, probably, than that. And the worst part, though, was not the immediate carnage. It was what happened over the next few years. Because all the soot from the wildfires, from the smoke, a lot of the dust and dirt and grind from the collision, the pulverized rocks, and so on, went up into the atmosphere, spread around in the currents of the high atmosphere and blocked out the sun for at least a few years, maybe up to a decade or even a bit more. And so the earth would have gone dark and cold. Even in proto-California? Everywhere, probably. There could have been little bits, you know, poking through, poking through.

56:30But it seems like really this was a time of coldness and darkness. And we see it in the rock record. We can see some of the chemical proxies that tell us about temperature. You can see how temperature took a nosedive. You can see a lot of the soot and stuff from the wildfires actually in the rock record, right marking that extinction. So if the earth went dark and cold, even if it was just for a few years, I mean, plants would not have had sunlight to photosynthesize, nor would the phytoplankton in the ocean. And so ecosystems would have collapsed as sunlight was starved from the plants and the plankton.

57:08And these ecosystems collapsed like houses of cards. The plant-eating animals didn't have anything to eat. They died. The meat eaters didn't have anything to eat. They died. And 75 % of all species died. Three out of every four species, period, did not make it through and died quite quickly. We don't know if they were all dead within a year or five years or 10 years or whatever. But we do know from really well-dated fossils that within a few tens of thousands of years at most after the asteroid, 75 % of stuff was gone, including all the pterodactyls, including all those reptiles that were living in the water, including the ammonites, those beautiful coiled, shelled sea creatures, and including every type of dinosaur except for one peculiar group of birds.

58:00And these were the modern style birds, the ones that had big wings and huge chest muscles to power those wings, the ones that had beaks instead of teeth, the ones that had really lightweight hollow skeletons, the ones that grew super quickly that went from a hatchling to an adult within a year at most. Only those birds survived. There were a bunch of birds that still had teeth and claws and long tails that were there flying over the head of T-Rex the moment before the asteroid hit, and they would not make it through. So the question really is, why were those birds so special? And I think when it comes down to it, they just held a winning hand of cards.

58:39When something changes so quickly, when the environment changes so quickly, you don't have time to adapt the normal processes of natural selection through random mutations, shaping your genome over the generations. You have to confront that disaster with whatever hand of cards you're holding. And dinosaurs like T-Rex and Triceratops, they had been utterly dominant for tens of millions of years. But now, all of a sudden, they were in trouble because they were big. They needed to eat a lot of different types of food. Some of them needed to eat a lot of plants, hundreds of pounds of plants a day.

59:13It took them a long time to grow from babies into adults. It would take a T-Rex like 20 years to grow into an adult. That's a long time to survive if the world has gone to hell. And they couldn't hide very easily. How could a T-Rex dig a burrow to hide itself away? Or how could a Triceratops just go and find a cave to hunker down in? It'd be really tough. So the animals that survived were ones that tended to be smaller, that could hide away more easily. They're ones that grew quickly. They're ones that reproduce quickly. They're ones that didn't need a lot of food. And when it comes to birds, one particular thing that allowed them to survive, it seems, was their beaks.

59:52Because this was just some little trivial factoid about these birds. There were plenty of birds that still had teeth, but some birds had beaks. All right. But when it came to that asteroid changing the rules of the game, all of a sudden, basically everything's dying. The forests have collapsed. There's no more leaves and stems and fruits and flowers to eat. All that stuff is gone. The plant-eating animals, they die. The meat-eating animals, they die. What is left? Well, one of the things that survives longest, and we see this today, if there's a volcanic eruption or a wildfire, everything might be obliterated.

1:00:27But seeds can survive. And they do survive quite long. They won't survive forever. But if you have to get through a few years or so, if you can eat seeds, that can be your ticket to survival. And those birds with those bees. I can eat seeds. I love seeds. Yeah, so there you go. So remember this. We got to remember this. When the nuclear apocalypse comes for us, eat your bird feet. That was such an inspirational speech. It might be what gets us through. You were the president in Independence Day saying, if we can eat seeds, we can all survive. I got chills. Yeah, me too. So if you take anything away from this conversation, any of you guys, well, first of all, if you take anything away, go out and, of course, buy my book.

1:01:12and leave five-star reviews online. Storybirds. Anyway, take that away. But the second thing, take away. Eating seeds can help you survive an apocalypse. And it probably did at the end of the Cretaceous. Something as trivial as that, which seems so trivial that in the moments before the asteroid hit would have meant nothing. It's just something you ate. It's like that's what your species was adapted to do and that's what you ate. Other things ate leaves and other things ate fruit and other things ate meat. But then everything changes. Seeds were the only thing left and all of a sudden that was your ticket to survival.

1:01:44But what's the connection between seeds and beaks? Because again, I can eat seeds and I don't have a beak. Yeah, we can eat seeds just because we as humans are so omnivorous and our teeth are quite good at eating lots of different things. But actually, we're quite unusual to be able to eat so many things. And it's not that no other dinosaurs could ever eat seeds, but beaks are really optimized for cracking seeds. They're like the best way you can eat seeds. We could eat more seeds if we had a beak instead of our teeth. And then, of course, things like T-Rex would not have been eating seeds. So it was just one of those things.

1:02:19It's not that birds were the only animals that could eat seeds. Some of the small mammals probably did as well. That's probably why they made it through. But it's just probably one of the reasons. And when it adds up to it, it's really, again, the hand of cards you're holding. It's birds. Some birds, again, most birds died. All the ones with teeth and long tails and claws. they died with T. rex and Triceratops. It's only the modern style birds that survived. And they had beaks. They grew fast. They could fly really well so they could escape any local danger fairly easily. They were small. They could hide away fairly easily.

1:02:52They lived on the ground or in the water. They didn't live in the trees. So when the forest collapsed, they weren't nesting in those trees. Their homes didn't disappear. So all of those things, when you add them together, It just gave birds a royal flush. And that's what they had to confront the asteroid with. And they made it through. But if small little things were different, little twists of fate or circumstance playing out in the minutes, the hours, the days after the asteroid, everything could have been different. And who knows what the modern world would have looked like? Who knows what would have made it through to survive, to repopulate the world?

1:03:29So I read this other really great book called The Rise and Reign of the Mammals. Oh, that's a fantastic book. Oh, my gosh. That is so good. Five stars. Five stars. Five stars. It's maybe the second greatest book in the world except for the story birds. You can guess who wrote that book. The Rise and Fall of the Dinosaurs is also in the ranking there. They're great. But you know what? None of them won a Royal Society Book Prize. So you have the title here. So, of course, all of your readers know your book is for the MRs. I don't have to pitch it. Well, the story of birds is going to be this year's winner.

1:04:01That's what I'm predicting. Well, I hope you're on the panel. Okay, thanks. Thanks. I hope we remember to submit it to the prize. That's the first thing to get a prize. There you go. Send it in. Send it in. Okay, but to get back on track, so, you know, there were mammals who made it through, and there were probably some, like, you know, there must have been some, like, reptiles who made it through. Yeah. Is eating seeds, like, a common denominator for all of the animals that made it through that weren't birds? not for every animal that made it through. So about 25 % made it through. And there were some other ways that you could make a living too.

1:04:37Some of the animals that survived, things like crocodiles and turtles, they lived mostly in swamps and in ponds and in rivers, in shallow water, in ecosystems that did not have plants or other photosynthesizing organisms at the base, but instead were detritus-based ecosystems. So it was basically eating decaying crap that's at the base of those food webs. Buffet time. After that asteroid hit, perfect. It was a global buffet if you were in those ecosystems. So you had fishes that would eat that stuff and then the turtles and crocodiles would eat them and so on. So that was another ticket out of the chaos.

1:05:16So it wasn't just only eating seeds was the only way you could survive, but it was one pathway to survival. And there seemed to have been others. But there were limited pathways to survival. And really nothing bigger than like a Siberian husky dog made it through, at least on land. So size, even if you could eat seeds and you were bigger, you were probably in trouble because it took you too long to grow into an adult. You needed to eat too many seeds to power your metabolism. So being small, really more than anything, was the number one thing you needed to be to survive. And I mean really small, like something that could fit in the palm of our hands is the best, probably body size to be that or smaller.

1:05:59And we had ancestors. We had tiny little shrew-sized furry mammal ancestors that also stared down the asteroid, made it through. And that's why we're here. We've been having too much fun, so we don't have time for my questions about the terror birds or the demon ducks or loss of flight. That is a shame. You know what they're going to have to do? Get your book. Read the book. Absolutely. We always need to leave people wanting a little bit more for these conversations. So the second half of the book is all about what happened after the asteroid and how modern day birds established themselves. So many of the birds we know today, the familiar birds, songbirds and parrots and different types of water birds and penguins and hawks and so on, they established themselves very quickly after the asteroid as part of the recovery.

1:06:49This was a wide open world. Endless opportunities were out there. And evolution went into overdrive and you had all these new types of birds. So I tell that story in the book. And evolution went so wacky that you got these incredible birds, like terror birds, which stood taller than a human, that were basically like a T-Rex reincarnated. These things became the top predators in South America. They had heads the size of horses, big, sharp beaks. Not for eating seeds. No, no, not these beaks. These were for ripping flesh. Heads the size of horses' heads or heads the size of horses? Heads the size of horses' heads.

1:07:23Yeah. Yeah. Not a head the size of a thoroughbred, but a head the size of a thoroughbred's head. But still, pretty terrifying. And so I talk about these elephant birds and demon ducks. Imagine a duck supersized by a hundred times the size and it's demonic, but not really because it was a plant eater. And these things lived in Australia for tens of millions of years until quite recently. our human ancestors ate their eggs. We find cooked demon duck eggs and archaeological sites and campfires. So we had human ancestors and cousins that confronted some of these birds. And there's so many more. There were once birds that soared on the thermals of the world like giant kites with wingspans of over 20 feet wide.

1:08:06A huge, fantastic aviary of extinct birds are out there. We only know them from fossils. I try to do them justice later on in the book. So there's a couple of chapters on those. And then, of course, about how some of those birds lost, gave up the very essence of birdness. They gave up flying, you know, and ostriches and cassowaries and emus and penguins and so on. They gave up flying so they could become adapted to other niches in the ecosystem. So they could become bigger, so they could become giant bulk feeding plant eaters. So penguins could go into the water and become big fish eaters and so on.

1:08:43There's a lot more. But again, I need to leave you all wanting more. So it's all in the story of birds. I promise you, it's all in there. And there's a whole lot of great stories about all the amazing things birds have done. And I think when it comes down to it, we just need to appreciate birds. They're fantastic diversity. There's over 10 ,000 species of birds today. That's about double the number of mammals. So yeah, okay. Dinosaurs died. Dinosaurs went extinct. It's now the age of mammals. Well, there's still like double the number of dinosaurs as mammals in the world today by that metric. And so when you look out and you see a magpie or a pigeon or a sparrow, I mean, you're looking at a real true dinosaur that's made it to the modern day.

1:09:28And I hope that comes through in the book. That's what I really want to convey. Well, I have a question for you from my wife, who's a biologist. She wants to understand how birds prepare for migration. Apparently, they put on a huge amount of muscle and their stomachs shrink to almost nothing. So her question is, what's the secret and how do we follow the bird dinosaur diet ourselves? Well, we're out of time here, so I don't know. I don't know. There's so much about birds I don't know, especially when you get into the amazing things birds do today. once you get into their migrations and their feats of cognition and intelligence and their songs and these kind of things.

1:10:10I know a bit, I write about a little bit towards the end of the book about a few of these things, but there's so much I don't know. I have no idea how birds are able to prepare for these migrations. It is otherworldly to me, but it's one of those things that we just must admire about birds. So I'm sorry to let your wife down there. I don't have any like top nutrition tips of how to be a bird to, you know, marshal the power of migration to become more fit and energetic. If you find out, let me know. That's just an idea for your next book. Well, then let me ask you a different question. If you went to an alien planet, right, you're on board the ship or landing on a planet, we think there's life on there.

1:10:48Are you expecting there to be birds or life in the air? How broad do you think this sort of evolutionary niche is? Well, I'd be curious to hear, you know, Kelly's view on this system. Do you actually know something about outer space and different planets and potential life on other planets and settling other planets? I mean, when it comes down to it, we just don't know. We've never found any fossils, definitive fossils of any life anywhere else. But I'm guessing that at some point in our lives, there's going to be a fossil from Mars that is found. Until then, though, we just don't know very much.

1:11:23But I would think that if you do have other worlds out there that are anything like Earth, there's going to be stuff flying around. This is a whole environment that's there to be colonized, if you want to think about it that way. And over time, evolution, it expands. I mean, it fits organisms to their environment. If there's opportunities, evolution will, not in any sort of direct planned out way, but it will over time really just fill the space and find ways to exploit resources and environments and ecosystems. And the air is vast. There's air all around us. And that's just a place you can live and a place that you can get shelter and a place where you can start to form ecosystems and communities.

1:12:06So yeah, I would expect the air elsewhere would be settled the same way if there's liquid water elsewhere or dry land elsewhere, that it would be settled in a similar way. But who knows, really? Kelly, I don't know. You know what you're talking about. I'm just blathering on. Daniel always ends our interviews with a question about, do you think you'd find the same thing on an alien planet? And so I will say nothing. This is Daniel's prerogative to ask our interviewee this question at the end. And so I will just say that, Steve, it was amazing having you on the show. I loved reading the story of birds, and the illustrations were great, and the photos were fun.

1:12:41I highly recommend that everyone head out and get the story of birds, which comes out today. Thank you, guys. Thank you so much. This is so much fun. We could have done this for hours, but we'll have to do it again. Yes, we will. Yeah, and I have a bunch of listener questions that I think you are the guy to answer, so I hope you'll come back. Well, we will circle back. Absolutely. Keep track of those questions. I love just being thrown random questions, like the stuff Daniel's been asking me. So let's do it again. All right. Well, I'll hold you to it. Until next time.

1:13:18Thanks, everybody, for listening. Please go and do us a favor and rate the show on whatever podcast app you're using. It really helps people find us. Daniel and Kelly's Extraordinary Universe is edited by the amazing Matt Kesselman. He really is a wizard. You can also find us online on Blue Sky, Instagram, and XDNKUniverse. Come engage with us. You can email us at questions at danielandkelly.org. We really do want to hear from you. And you can find our website, www.danielandkelly.org, where you'll also find an invitation to join our Discord, where everybody comes and talks about the amazing universe.

1:13:58And we also have the most amazing moderators. This is an iHeart Podcast. Thanks for joining us.

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