Prehistoric Penguins

The Ancients

This episode explores the remarkable evolutionary journey of penguins from their origins as dinosaurs to their reign as colossal apex predators in the post-asteroid Southern Ocean.

Key takeaways

• Dr. Steve Brusatte clarifies that modern birds are literal dinosaurs, with penguins evolving rapidly after the K-Pg asteroid impact 66 million years ago.
• The oldest known penguin, Waimanu, lived just a few million years post-extinction in Zealandia and was already fully aquatic but surprisingly large.

Main topics

• Post-K-Pg avian evolution and ecological radiation
• Prehistoric penguin gigantism and marine ecology

Notable quotes

"Birds are dinosaurs. It's not a technicality. It's not a turn of phrase. They literally are part of the dinosaur family tree."

Conclusion

The episode reframes penguins from modern Antarctic icons to ancient marine apex predators

Transcript preview

Speaker 4 (0:00) Ever wondered why the Romans were defeated in the Teutoburg Forest? What secrets lie buried in prehistoric Ireland? Or what made Alexander truly great? With a subscription to History Hit, you can explore our ancient past alongside the world's leading historians and archaeologists. You'll also unlock hundreds of hours of original documentaries with a brand new release every single week covering everything from the ancient world to World War II. Just visit historyhit.com slash subscribe. Penguins. Today we think of them as the fluffy, small Antarctic birds, perfectly built to dart through the cold waters of the southern hemisphere, hunting prey tens if not hundreds of metres beneath the water. The iconic aquatic bird. But penguins weren't always so cute and cuddly. They descend from dinosaurs. And for millions of years, Penguins were prehistoric apex predators in the Southern Ocean, the largest being more than 6ft tall, earning the name Colossus. Yes, the largest prehistoric penguins that we know of. They weren't just ferocious sea predators, they were also the size of many NBA basketball players today. So what do we know about these early penguins? How do they emerge after the extinction of the dinosaurs? And how do we get from these prehistoric beasts to the lovable creatures we know today? Welcome to the Ancients, I'm Tristan Hughes, your host, and this is the story of prehistoric penguins. Our guest is Dr Steve Brassati, personal chair of paleontology and evolution at Edinburgh University, and the author of the brand new book, The Story of Birds. Speaker 4 (2:02) Steve, welcome back. Great to have you on the show, as always. Speaker 2 (2:05) As always, we talked about terror birds. Now we can talk about penguins. I Speaker 4 (2:10) don't think I've been so excited for an episode. Ever? In some time. Oh, Speaker 2 (2:14) wow. Speaker 4 (2:14) Okay. And that's a high bar. Okay, Speaker 2 (2:17) okay, okay. I'm trying to live up to it. Speaker 4 (2:19) Because these cute and cuddly things, they have their own prehistoric story when they weren't so small. And yeah, as we know them today, they have their own prehistoric story. Very cool one too. Speaker 2 (2:31) They do. And I must say a shout out to my son, my six-year-old son, Anthony. This little plush penguin here, it looks like something I could have just plucked off his bed this morning. Not that I would have done that, you know, before I came to meet you guys. But he loves penguins and he must have at least 10, if not 20 stuffed plush. Penguins of all kinds people give them to him as gifts all the time somebody goes to you know to New Zealand or to To South Africa or somewhere, you know a family friend or a friend of a friend They know to bring Anthony a penguin because he loves him that much and in fact if you ask him What his favorite dinosaur is? You know, you might expect a six-year-old boy to say t-rex or spinosaurus or velociraptor, but he'll say penguins Because he knows birds evolved from dinosaurs, of course, because I teach him the good stuff. But he's not super into the ferocious canonical dinosaurs, but he absolutely loves penguins. And what he didn't know, but what he knows now and what he loves is that penguins do have this. prehistoric past where they weren't always these cute, cuddly, fluffy, charismatic little creatures. They had a darker history. Speaker 4 (3:43) And can we also say that penguins are dinosaurs? They Speaker 2 (3:46) absolutely are, you know, in the sense that all modern birds are dinosaurs. And the way, look, I know it's weird to think about it. I get this all the time, you know, in the story of birds and in my new book, you know, the early part of the book is establishing what we mean when we say birds are dinosaurs, how birds evolved from dinosaurs. And I know it sounds weird because when you look at a sparrow or you look at a crow or you look at a penguin, it doesn't look anything like a T-Rex, like a Triceratops. But. Dinosaurs were a very diverse group. They lived for a long time. They're kind of like mammals today. There's all kinds of mammals, big ones and small ones, bats and whales and elephants and horses and mice and people and everything in between. Similar with dinosaurs. There were lots of different types of dinosaurs. And there was one type of dinosaur that got small. grew wings and started to fly. Those were the birds, similar to how there was one type of mammal that got small, grew wings, started to fly. Those are the bats. So we should really think of birds as the dinosaur equivalent of a bat. But the difference, of course, of course, is that all the other dinosaurs have died, leaving only birds. And if you could imagine, I mean, it's kind of morbid because it means we wouldn't be here, but if every type of mammal died except for bats. That's kind of the world we're in with birds. So yes, birds are dinosaurs. It's not a technicality. It's not a turn of phrase. They literally are part of the dinosaur family tree. They evolved from other dinosaurs. They are dinosaurs. That means that a penguin, when you see a penguin in a zoo, or if you're lucky enough to go on a cruise to Antarctica or to New Zealand to see penguins, you're looking at dinosaurs. You're going dinosaur watching. And so Speaker 4 (5:24) how Speaker 2 (5:25) far back does Speaker 4 (5:27) the story of penguins go? Speaker 2 (5:30) I would start the story at about 66 million years ago when the asteroid ended the age of dinosaurs and knocked off T. rex and Triceratops and the long-necked dinosaurs and all the classic ones. That really was the big turning point in dinosaur history. Pretty much everything with birds today. came from that moment, hinged on that moment. Birds evolved before. There were birds around with T. rex. There were proper birds with wings and feathers that were flying and flapping and fluttering and gliding and soaring over the heads of T. rex and Triceratops and the other dinosaurs. And so the classic features of birds, their feathers, their wings, their wishbones, their lightweight skeletons, their fat... fast growth rates, their high metabolisms. Those things all evolved from their dinosaur ancestors. But then the asteroid hit and it more or less wiped the slate clean. And out of these few surviving birds came the many groups of birds that we know today, including penguins. And they all seem to have evolved quite rapidly. Many of these bird groups within the first few million years of that asteroid there was just so much empty space So much abundant opportunity if you were one of the lucky 25 % of species to survive You had these opportunities and the birds did and penguins came out of that. So I would start the story of penguins there. It's not that a penguin itself survived the asteroid. As far as we know, there were not proper penguins living before the asteroid during the time of T-Rex, but they show up in the fossil record quite soon after. Speaker 4 (7:04) And when they show up in the fossil record, have they lost the ability to fly already? Is that a big moment? Speaker 2 (7:11) That's right. So one of the major things about penguins today is that they cannot fly. They are birds that cannot fly. Or... At least they can't fly in the air. When you watch them swim underwater, they move their wings in a similar way that other birds do in the air. So they're kind of using their wings to fly through the water, but they cannot fly in the air. They gave up that ability to fly, and it was basically one of these evolutionary trade-offs. They stopped flying in the air, they streamlined their bodies into these torpedoes, and they turned their wings into flippers to be used for swimming. So they stopped flying in the air, they started swimming. The very first penguin... fossils that we have, which are around 61 to 63 million years old, the dates always move around a little bit, they are already penguins in the sense they don't fly in the air anymore, they have wings that look like paddles or like flippers, they were swimmers, so they had already made that trade-off. They're more primitive than modern penguins in some ways, their paddle wings are not quite as big, not quite as powerful, but they are unmistakably penguins. And Speaker 4 (8:16) where in the world does this transition happen? Speaker 2 (8:20) It happened in the south. Everything in penguin evolution, as far as we know, has happened in the south. Penguins have only barely ever snuck just a little bit north of the equator. And these are the penguins today in the Galapagos. They're our Speaker 4 (8:34) penguins. And they Speaker 2 (8:35) ride these cold water currents. That's why they're able to get north of the equator. But there have never been penguins as far as we know. But we're pretty certain of this because the fossil record is pretty good. Never penguins here in Europe. Never penguins in Asia. Never penguins in North America. Now, there used to be puffins that gave up the ability to fly. that became these flightless swimming birds up north. Things like the great auk. They were kind of the northern version of penguins, but they were not penguins. They were not closely related to penguins. They were puffins. They were more closely related to gulls. So what seems to have happened over history is that you had these gull type of birds become these flightless swimmers up north. You had penguins do it down south. We don't know exactly where. The first penguins lived, but the oldest fossils come from New Zealand. And there are still penguins in New Zealand today. So there's a good chance that the origin of penguins might have happened either on New Zealand or somewhere in that vicinity. In fact, New Zealand is... basically the last remnant of what used to be an entire continent, like a real-life Atlantis that's basically under the waves, which maybe we'll get to. But maybe it was this lost continent of Zealandia. Yes, let's explore this now. What is Speaker 4 (9:48) Zealandia? It's Speaker 2 (9:49) a lost continent. It's a real Atlantis. You know, we talk all the time, and as I'm sure you guys do even more than me, about these legends from human history of sunken lands and lost worlds. And Atlantis is always the one we learn about, you know, as kids. and it has this hold on our imagination. And I don't know, you would have to tell me the latest on what historians and archaeologists think about Atlantis and if it was based on a certain flood or if it was based on a certain island. But I can tell you there really is a lost, sunken continent. that does exist, that's there, but is mostly engulfed by water now, and that is Zealandia. It is an entire continent that is nucleated around New Zealand and New Caledonia. They're the only parts that really emerge from the waves today. The rest of it is underwater, but it is very much a continent. It has well-defined boundaries. It's made of the same types of rocks that continents are. So a continent isn't just something that's above the waves. No, no, you have to be made of a certain type of rock. basically granitic, you know, granite type rocks to be a continent and you have to