Science Friday - The Rise Of Mammals And A Cephalopod Celebration. June 17, 2022, Part 2

Episode Date: June 18, 2022

The Wild and Wonderful World of Mammals Mammals may be the most diverse group of vertebrates that have ever lived. (Don’t tell the mollusk enthusiasts over at Cephalopod Week.) Many people share their homes with another mammal as a pet, like a dog or cat. The largest creatures on earth are mammals: Ocean-dwelling blue whales are the biggest animals that have ever lived, and African elephants are the biggest animals on land. And lest we forget, humans, too, are mammals. The history and diversity of mammalians is the subject of a new book by paleontologist Steve Brusatte, “The Rise and Reign of the Mammals.” Steve joins Ira to talk about why mammals have been so successful over the years, and why extinct mammals deserve as much love as the beloved dinosaurs.  A Squid-tastic Night Out  How do you fossilize a squishy squid? Do octopuses see in color, and do they have arms or tentacles? Which came first, the hard-shelled nautilus or the soft-bodied octopus, squid, or cuttlefish? And what does ‘cephalopod’ mean, anyhow?   This week, Ira ventured to the Maritime Aquarium in Norwalk, Connecticut for a special Cephalopod Week celebration. He was joined by experts Barrett Christie, the director of animal husbandry for the Maritime Aquarium, and Christopher Whalen, a postdoctoral researcher and invertebrate paleontologist at the American Museum of Natural History in New York.  They also discussed the challenges of caring for cephalopods in an aquarium environment, some of the amazing abilities of these animals, and what it’s like to discover a previously unknown cephalopod genus and species in fossilized material stored in museum archives. Together, they tackled audience cephalopod questions large, small, and multi-armed.   Transcripts for each segment will be available the week after the show airs on sciencefriday.com. Subscribe to this podcast. Plus, to stay updated on all things science, sign up for Science Friday's newsletters.

This is Science Friday. I'm Irafledo. You know, I may be a little biased, but I think mammals are among the most incredible and diverse creatures on the planet. Now, that is not to say we don't love our cephalopods. Of course, this is cephalopod week, and we will have more on that later in the hour. Many of us, right, we have mammals as pets. You have a dog, a cat, maybe a gerbil or a hamster, and the largest creatures on earth are mammals. You've got your blue whales in the ocean and your African elephants on land, and we can't forget we ourselves are mammals. So this hour, we're going to investigate the wide world of mammals, including where do they come from? Evolutionary, wise I meet, with my guest, Steve Brousscibi, paleontologist and author of the

rise and reign of mammals. He's based in Edinburgh, Scotland. Welcome back to Science Friday, Steve. Hi, we're always a pleasure to chat with you and really excited today. talk mammals. We've talked dinosaurs before. I've studied dinosaurs a lot throughout my career, and now I've moved on a lot to mammals because, as you say, mammals are really fascinating. And mammals are us. We're a man. All right. Let's get into it. I want to invite my audience in on this, too, because we're going to be taking questions this hour. We want to know from them, what do they want to know about the post-dinosaur rise of the mammals? From the ones that have been long extinct, and I don't think a lot of people knew that there are long-extinct mammals, but I did reading your book,

to our closest relatives. Our number, of course, is 844-8255-8-4-8-4-Sai Talk, and as always, you can tweet us at Cy Fry. So let's address the, I have to say, at the elephant in the room. I don't know if there's a pun intended there. They just come out. As you say, you're a dinosaur guy. What got into you to start talking about mammals? I think it's a natural progression, really. So I started my career studying dinosaurs. I did my PhD on dinosaurs. I've written books about dinosaurs.

And I love dinosaurs. I'll continue to study dinosaurs. But as I've studied the origin of dinosaurs and then the evolution of birds from dinosaurs and then the extinction of the dinosaurs, I think it was natural to start to wonder, well, then what happened? When the dinosaurs died, what happened? And mammals were what happened. mammals took over from the dinosaurs, that's ultimately where we come from and the 6,000 other

species of mammals that share our world, everything from our pet dogs and cats to bats and whales and whales and that elephant in the room and whales and so on. But really the story of mammals goes back much farther than that. It's a story that is 325 million years of evolution, and I think it's a fascinating story. So a lot of my research has turned to mammals and now with the new book I'm writing about mammals too, and I'm loving it. Well, how were mammals possible? If we had all these dinosaurs, I mean, were they holding back the evolution of or the, you know, the population of mammals?

I think there's a bit of a preconception. And we see this sometimes in textbooks and documentaries and so on, that dinosaurs had their day and then they died. The asteroid came down, wiped off the dinosaurs, and then mammals evolved to take their place. And it's certainly true that mammals took over from the dinosaurs, but mammals and dinosaurs actually go back to the same time and place. They have the same origin story. They were part of this new wave of diversification in the Triassic period about 225 million years ago. After this terrible mass extinction, back on the supercontinent of pangia, both dinosaurs and mammals got their start at the same time.

And of course, dinosaurs were destined for grandeur. Some of them became larger than Boeing 737 airplanes. And mammals had to stay in the shadows. The dinosaurs kept mammals small. And for 150 million years or so, mammals and dinosaurs lived together. And mammals never got bigger than a badger. But the more fossils we find, the more we see that mammals were really good at living in those small-bodied niches. They were good at living anonymous.

living underground, coming out at night. And there were mammals that could swim. There were mammals that could burrow. There were mammals that could climb. Mammals that could glide through the trees on wings of skin. They were just all small. And the more we learn from fossils, the more we see that, yes, dinosaurs kept mammals small, but mammals did the opposite.

They kept dinosaurs big. And for 150 million years, you never had a T-Rex the size of a mouse or a triceratops the size of a rat, because the mammals were so good at holding down those roles in the ecosystems. That is really cool. And I think one of the most interesting parts of your book is that some of the mammals that didn't make it, as you say, there once were wee mammals that glided over the heads of dinosaurs, others that ate baby dinosaurs for breakfast, armadillos the size of Volkswagen, sloths so tall they could dunk a basketball, Thunderbeast with three-foot-long battering ram horns. These were the early mammals?

Or are these the ones that just died out and never made it to this time? These are a variety of mammals that once lived, that no longer are with us. I talk about all of them in the rise and rain of the mammals in the new book. And some of them are ones that lived with dinosaurs. As you say, these ones that glided over the heads of dinosaurs, or this mammal called Repenamemus that lived about 125 million years ago, it was buried in a volcanic eruption. It was preserved as a fossil so quickly and so. pristinely that his last meal was petrified in its stomach and that last meal was a little baby

dinosaur, a very sad story really, but I mean mammals once ate dinosaurs and then after the dinosaurs died, all of these other mammals evolved and it was then that we got things like woolly mammoths and the giant ground slots and these car-sized armadillos and so on. So the point really is that mammals today are extraordinarily diverse, over 6,000 species, everything from bats to whales to humans, to humans, but the mammals that once lived in the past were even more spectacular, and we have their fossils, we can study them, and they are all part of our evolutionary story. And what happened to them? Why did they die out? Is that just something natural? Some of these mammals, yeah, some of them died out just just naturally, just normally as species do, as climates change,

as environments change, as new groups rise up and species compete. But a lot of the lot of these big megafauna mammals, the really charismatic ones, the woolly mammoths, the saber-tooth tigers, the dire wolves, the giant slots, the ones that you see in natural history museums that are the stars of the Ice Age movies and so on. These mammals lived quite recently. They went extinct most of them only about 10,000 years ago. Our ancestors, our Homo sapiens predecessors knew these mammals. They encountered them. They hunted them. And it was probably largely because of humans through hunting and through changing environments and so on that doomed a lot of those mammals.

Really continent by continent, whenever humans arrive not long after a lot of the at large mammals died. So maybe if it wasn't for us, there might still be woolly mammoths and saber-toothed tigers. Let's talk about some of the creatures that really looked like reptiles, but actually more related to us. like the Dimetrodon. Talk about that. So let's go back 325 million years. Just a snap on the finger. 325 million years.

Put your mind back. This is back in what's called the Pennsylvania period of geological time or what we call the Carboniferous period in Europe. And the world was much different then. This was the age of the coal swamps, the first big, vast jungles in Earth history. There were trees that stretched 100 feet into the but these were not the trees we're used to today. These were primitive plants. And there were

dragonflies, the size of pigeons. There were millipedes, the size of humans. There was so much carbon dioxide in the atmosphere, so much humidity. It was this world in those swamps, those trees getting buried, that produced a lot of the coal that we mined today. And it was in that world, almost an alien world, at least to us, that a small event happened. It was, was a small evolutionary step, but it had profound consequences. And on the great family tree of life, a new group split off. And this new group went their own way. And reptiles went the other way. And this new group is called the synapsid group. And all that defined them was that they had a hole in their skull behind their eyes that jaw muscles could attach to. So basically, they had more

and bigger jaw muscles. So they could bite a lot stronger. These synapsids were what gave rise to mammals. These were the mammal antecedents. So this is the start of the mammal family tree. And among the very first synapsids were things like Dimitradon, this animal with a big sal on its back. It walked on all fours, its arms and legs stuck out to the side, kind of like a lizard or a crocodile. It looks kind of like a lizard or a crocodile or a dinosaur. As often mistaken as a dinosaur, you often see it in the dinosaur toy sets.

You will see it in the new Jurassic World film. You'll see Dimitradon in there. But it's not dinosaurs. Is that because of you? I know you were the advisor on the film. I was the valiantology consultant on the film. I wish I could say that I convinced Colin Trevor, the director, to put in some early mammals.

But no, he loved Dimitradon from the moment that I first met him. Because it is an iconic animal. You see it in a lot of museums. It does look like a dinosaur, but believe it or not, it is an early relative of ours. It is more closely related to us than it is to, a T-Rex or a triceratops. And it was animals like Dimitradon that really inaugurated the mammal line hundreds of millions of years ago. You know, we keep thinking that one of the unique features

of mammals is that they're warm-blooded. Where did that start? How did that happen? There are a lot of different things that together make what we call the mammal blueprint, the features that define what a mammal is that differentiates mammals from all other animals. And these are things like having hair, feeding your baby's milk, having really big brains, having really keen senses of smell and hearing, having canine and incisor and premolar and molar teeth that conserve so many functions at once and can chew food. All of these things together really define what mammals are. And another part of that package deal is warm-bloodedness.

And that's a really unusual thing. Birds are warm-blooded as well. So it's not only mammals, but mammals are some of the few animals that are warm-blooded. And really what it means is that we can control our body temperature. We feel this every time we go outside in the depth of, say, a Chicago winter. I grew up in the Chicago area. You go outside in winter, it's well below freezing. You don't freeze, you know, because your body temperature is high.

You have this internal furnace inside you. It doesn't matter if it's cold. It doesn't matter if it's in the morning. If you're in the shade, you don't have to go out and bask in the sun. like a lizard or a crocodile does in order to warm up. So being warm-blooded, being able to regulate your body temperature, control it internally, have a high, constant body temperature. That's a real superpower.

It means you can live all over the world. You can live in cold places. But it means that you have to be able to take in a lot of energy and a lot of oxygen to power that internal furnace. So mammals evolved a way to do that early in their history. All right. We're going to have Steve Rossidy stay with us, talking about the, Rise and Rain of the Mammals. This is a new book.

Excellent new book. Our number 844-8255. Stay with us. We'll take your questions after the break. This is Science Friday. I'm I Refledo. We're talking this hour with Steve Broussdi, author of the Rise and Rain of the Mammals.

Great new book. And we're taking your questions. We want to know what you want to know about the post-dinosaur rise of the mammals. Our number 844-724-8255. 844 SciTalk, or you can tweet us at SciFri. Let's go to the phones. Let's go to Blue Sky in Tempe, Arizona.

Hi, Blue. Hi, Ira. Hi, Steve. My question is, of course, the fossils we traditionally find are many centuries old. But my question for you is, take something like the Mount St. Helens eruption. Did that produce new fossils? That's a good question. And I don't actually know the answer to that.

I haven't studied that volcanic eruption, and so you've now given me something to read up on. My guess is it might have because there are a lot of instances in the fossil record, like this fossil I mentioned from China of this mammal with a baby dinosaur in its belly, where animals are buried very quickly by volcanic ash. And, you know, Mount Vesuvius erupting and burying Pompeii and preserving a lot of those humans. That's a similar sort of thing.

So Mount St. Helens, it might have actually buried some fossils. I'm going to read up on that. That's a really interesting thing to think about. Thanks for your question. Thank you. Steve, let me ask you this question that I've been wondering about. And because you mentioned the formula for a mammal with the hair and the warm-bloodedness. Let's talk about that hair because you say that in the beginning,

the hair was a sensory organ and not something for warmth. I both love and hate talking about hair. I'm losing my hair rapidly. But it's one of those things that make mammals mammals and mine's thinning out. Hair is a sublime thing. You think about all the animals out there. And nothing else has hair, only mammals. And hair does a lot of things for mammals.

It helps keep us warm. It helps regulate the body temperature. That's an important part of being warm-blooded, being able to regulate your body temperature. And in that sense, hair is kind of the equivalent of closing your windows in the winter when the furnace is on. If you're burning all that energy, you want to make sure you can keep it in. So hair does insulate, but also a lot of mammals use hair as whiskers for sensory reasons. Hair is also connected in a very integral way with our skin, with the system of glands that can waterproof our skin. And so hair does a lot of different things.

It evolved somewhere in the early history of mammals. We have some evidence that some of these proto-mammals, these synapsids that were living hundreds of millions of years ago, maybe had hair. We don't find the fossil hair itself, but we can see the little pits on the bones where the nerves and blood vessels feeding the hair would have run through so we can infer it. But then with some of these volcanoes in China, some were Jurassic in age, so there are kind of 160. 60, 170 million years old and then later ones were Cretaceous in age, like the what I mentioned burying that mammal that ate the dinosaur. With those volcanic eruptions, they buried so many mammals and they preserved them in such a delicate way that you can see the hair all over the bodies of these mammals. I've studied some of these mammal fossils in China. I've always felt

as a huge privilege to hold these fossils in your hands. You can see this 170 million-year-old fossilized hair and you can really sense just how important hair is. You'll have such a cool job. It is. It is. It is. I always have to remind myself how fortunate, you know, people like me are, that we get to dig up dinosaurs and mammals for a living.

You get to dig up something that no one else has ever seen before. To me, that's the beauty of it. Yeah. It's remarkable, isn't it? How does that feel? I mean, you're standing over something. He said, whoa, never seen. daylight in the hundred million years, no one's, no one's ever seen it. I mean, as you know,

you can tell for me, I'm pretty locacious, just kind of talking and talk of it. I get passionate about something, but this is one of the things I find hard to put into words, to be honest. When you're out looking for fossils, you know, you find something, whether it's a bone or a tooth or a shell, and, you know, you are the first person to ever see this thing. It's millions of years old. It's a clue from another world. It's hard. I mean, how do you explain love? You know, I don't know. It's like that kind of thing. Poets could do it better than me. Yeah, well, let's see what our listeners are doing. Anna, in Boston, hi, welcome to Science Friday.

Anna, go. Hi. Hey, there. Go ahead. So my question is related to kind of the size of mammals and how it's changed throughout periods. I heard that in the Carboniferous era, the oxygen levels were a lot higher, and as a result, insects got really big. And I was curious if other animals had also gotten large, and that was because of two levels, that was because of, you know, evolving to deal with larger prey.

But, yeah, if you could speak at all about how they've reacted to different sorts of atmospheric levels. Yeah. Yeah, that's a great question, Ann. I'm glad you brought up size because, yes, back in the Carboniferous, this time of the coal swamps, there were such big jungles and there were so many trees that were photosynthesizing. They were just pumping out oxygen, and the oxygen levels just went stratospheric. And so that's why you had dragonflies. the size of pigeons, if you can imagine something as grotesque as that.

And so there was more oxygen in the atmosphere then. That's true. And that means that some animals did get a lot bigger. Now, there were other reasons, though, later, that mammals got bigger. As I was mentioned earlier, mammals were living alongside the dinosaurs for 150 million years. They never got bigger than a badger. The dinosaurs were just keeping them down. But then once the dinosaurs died, when that asteroid hit, everything changed. T-Rex was gone. T-Rex was gone. T-Rex was gone. All of these roles in the ecosystems, in the food webs, were suddenly open. And some mammals survived that asteroid. We had ancestors that stared down that asteroid because they were small, because they were adaptable, because they could burrow and hide and grow fast and reproduce fast and eat lots of

food, that was the winning lottery ticket when that asteroid hit. And then those mammals had a new world in front of them. And within two or three hundred thousand years, you have mammals the size of pigs. Within one or two million years, mammals the size of cows. So mammals ballooned in size once they have the opportunity with the dinosaurs disappearing. And a big part of my work, a lot of the fieldwork I do. In fact, I was just there. I was in New Mexico working with my students, my colleagues, great teams of people, Sarah Shelley, Arnella Bertrand, Greg Funson, my postdocs, and Tom Williamson, my great colleague in New Mexico, and Paige and Ha Hunts at Sophia and Zoe, my PhDs, I got to get their names, and they do all the real hard work. I just talk about it and

write about it. But we are out there collecting fossils of those very mammals that were living right after the asteroid, and they became bigger because they finally had the chance to do it. And of course, then mammals continue to get bigger, culminating in blue whales today. The biggest things that have ever lived in Earth history, I don't think we appreciate that enough. You know, how glorious is it that we can say we share a planet with the biggest things that have ever lived? And I think if whales were extinct and all we had were some petrified bones, we would hold them in as much esteem as we hold the dinosaurs.

Wow, and I hope that answers your question. Yeah, thank you so much. You're welcome. are they still getting bigger, Steve? Ira, that's an excellent question. And it's a subject I don't know much about, but I read a lot of the technical literature on this when I was writing the rise and rain of the mammals. And it does seem like whales have continued to get bigger over the last several tens of millions of years.

And particularly the baleen whales, the ones like the blue whales, that filter feed. And basically, you know, they can just open up their mouths and engulf, you know, pool size volumes of water and just filter the krill. So they're just eating machines. And so it does seem like they have gotten bigger and bigger. And maybe they will continue to get bigger and bigger if we give them the space to do it. You know, they are so endangered. The blue whale populations, at least at one point,

it's something like 99% of them were eliminated. So if we give them the space and the time to get bigger, I think there's every chance that they might. Yeah, that's a point well made. Let's go to Danny in Houston. Hi, Danny. Hey, good afternoon. All right.

Thank you to take my call. Hi, go ahead. My question, thank you. My question for your guest is if he could maybe talk to, I'm not sure if this is his expertise, but if you could talk to the concept of missing link between our ancestors and us today, I talk to my friends about that all the time. What is the missing link, I guess, as a concept? But good question. Steve, is that in your expertise? Speculation? Yeah, Danny. Yeah, definitely. So I teach

evolution here at the University of Edinburgh. I do a first year course. And we talk about these subjects. And the concept of a missing link is something that's, it's batted around a lot. You see it a lot in textbooks and on television shows. It's just kind of in the pop culture. You know, we're searching for the missing link. As scientists, we don't really hone in on one link that's missing that if we have it is going to tell us all the secrets. Really, what we have are series of transitional fossils that tell us a lot about, for instance, how whales evolved from mammals that once had hooves and once lived on land. We have fossil after fossil that gives a sense of that sequence.

You can read those almost like the pages in a book or like the stills, you know, that would make a moving film. And we have the same for our ancestry. We have a lot of fossils, mostly from Africa, from the last five or so million years, that show how a type of ape basically came down from the trees, started walking on two legs, still was pretty good at climbing, so at first retained pretty long arms. But they came down, they started walking on two legs,

then they got bigger brains, their hands were freed to do other things, to make tools and so on. And it was really that progression that culminated in us. And what I find remarkable about human evolution is the subject I didn't know a huge amount about until writing the book, and I'm still no great expert on human evolution. There's lots of other books that focus on this particularly. I only give it a little bit in the last chapter of the rise and rain of the mammals

because I don't want to make it all about us. But the thing that really fascinates me is that up until about 40,000 years ago, there were always multiple species of humans sharing the planet. And oftentimes there were numerous human species living together in the same environments, competing for the same resources. And it was only about 40,000 years ago that the last of these, the Neanderthals, died. Now, we absorbed a lot of their genes because we were able to mate with them and hybridize with them. But now it's just us, homo sapiens, alone, pondering where we came from.

So I hope that answers your question, you know, and getting to Danny's question, I mean, a lot of people, because they've watched this over a period of time or films or learned it in school, they think that evolution means we came from the apes, right? We came from chimpanzees or the apes in the jungle. That's not true at all. We have a common ancestor. We did not descend from them, right? Absolutely.

So, you know, we did come from an ancestral ape, but we did not evolve from chimpanzees. Chimpanzees are our closest living relatives. We share 95 plus percent of DNA with them, but we did not evolve from a chimpanzee. Chimpanzees and humans, we go back, about somewhere between kind of five and seven million years ago we had a common ancestor, but we both went our own ways. And chimpanzees have continued to

evolve during those five to seven million years the same way. Humans have evolved in their own way over those five to seven million years. So today's chimpanzees are a lot different from what that ancestor would have looked like. Danny, I hope we've given you a lot to discuss with your friends now. Definitely, yes. I appreciate all the information and all the work y'all do. Thank you so much. Thanks for listening. This is Science Friday from WNYC, Stu. I'm Ira Plato. We're talking with Steve Brousotti, author of The Rise and Rain of the Mammals. He's based, I always love it, that you're based in Edinburgh. What a nice place to be living, Steve. It's a great place that I land. I've been here about 10 years. I come from the Chicago area, as I mentioned earlier, but it's a wonderful place.

My wife's from England, and we've settled here. We have a little boy, you know, Anthony is two and a half now, and he's a Scottish boy. It's the most amazing thing. And it's also amazing. I wrote the book, really, during, you know, the first few lockdown. and when Anthony was very small. So I wrote a lot of it as I was learning how to raise my very own little mammal as he was teething, as he was drinking milk as his hair was growing out. So it sounds trite, but it's really true. Just being with him and learning from him really helped me write the book. And so what's next for you?

You've done the mammals now. You've done the dinosaurs. Where do you go from here? I don't know. I love writing these books. I love taking the science that we do and communicating it as broadly as I can, whether it's with the books or whether it's working on films like Jurassic World. You know, I'm very fortunate to have these opportunities.

I owe a lot to you, Ira. As you know, you reviewed my dinosaur book for the New York Times back in 2018. That review really helped establish that book. It's a great book. I'm just appreciative that people are interested in the things I study. I think we're lucky as paleontologists that fossils just have this connection with people. And I just love communicating that joy and that enthusiasm that I have and that I've had ever since I was a teenage. Well, you know, what I wrote about in that review and which I still see in your work and in this book is that you discover new young scientists for us from all walks of life, every different place in the world, that I think people would never discover before for themselves.

One of the great privileges of being a professor and running a lab is I get to have postdocs and students and people want to come work here. So I get to work with very interesting people from all over the world. and they really do come from all over the world from so many different backgrounds. And there are amazing young scientists that are working with me now. They bring so much enthusiasm, so much energy. They bring the new ideas. So I am just completely committed to doing everything we can to make sure that this field of ours is as open and accessible as possible. And I hope things like writing books and working on films and stuff, bringing the research to the public is a small part of doing that.

So what research, where did you got your spade or your pick, going now these days. The last three years has been rough because with the pandemic, we haven't been able to get out. And of course, you know, having a young kid at home, I haven't been able to get out as much. But we were out in New Mexico a few weeks ago, working with Tom Williamson and his crew in Albuquerque. And we were just out for about five days. It was a short trip. But we found a lot of good stuff.

We found a lot of mammals, not only mammals, but other things that were living with them in that brave new world after the asteroid, the turtles and the fishes and the reptiles and so on. But we do also do a lot of work on the Isle of Sky, my parents, who I know we're listening. They'll be coming up visiting us in Scotland soon, and we're going to go to Sky, and I'm going to put them to work. I'm going to have them try to find some more dinosaur and mammal fossils for us. This being vacation season, is it possible for us? We mortals to go watch a dig or to observe any kind of excavation here where scientists are working? Yes, it is. And there's a couple ways you can do it.

Some museums are actually built on fossil sites, so the labradorian. Rea tar pits in Los Angeles that I talk about in the book, there's active excavations. The Ashfall Fossil Breds in Nebraska, there's active excavations. You go to the museum, you will see people digging. But a lot of other museums also have public programs. Museums like the Burping Museum, close to home in Rockford, Illinois. They take people out every summer. So look at your local museums or look farther afield at what museums are doing if you want to go

out and dig your own dinosaurs or mammals. There's lots of opportunities. Well, good luck to you, Steve. and thanks again for the book, The Rise and Rain of the Mammals, another terrific book from you. Thanks for taking time to be with us today, and good luck.

Always my pleasure. You're welcome. Steve Brousotti, author of the Rise and Rain of the Mammals. We have to take a break. And when we come back, diving into the Cephalopod Week celebrations, yes, we're headed to the aquarium,

a conversation about caring for cephalopods in the aquarium. How do you do that? And how do you discover new ones that are right, literally right beneath your nose, I guess, inside a museum, how they discovered one. And we recorded this show this week at the Maritime Aquarium in Norwalk, Connecticut. We'll be right back with that after the break. Stay with us. This is Science Friday.

I'm Iroflato. We're coming to you from a Cephalopod Week celebration at the Maritime Aquarium in Norwalk, Connecticut. Hey, thank you all. Let me welcome my guests. our first guest, he's the director of animal husbandry here at the Maritime Aquarium, is going to tell us what it's like to work with octopuses. He's written the go-to manual on cephalopod care. Please welcome Barrett Christie.

My next guest, he's a postdoctoral researcher and invertebrate paleontologist at the American Museum of Natural History, you know, down the road apiece in New York City. And earlier this year, he described a heart. whole new cephalopi found in fossil records. Please welcome Christopher Whaley. Thank you about being with us today. First question to Barrett. Tell us a bit about what you do at the aquarium.

What does it mean to be the director of animal husbandry? Yeah, sure, thanks. So here at the Maritime Aquarium, we have a very diverse collection of animals. We have 20-some-odd biologists that have different specialties, and we manage them in order to care for the huge variety of animals here at the aquarium. almost 6,000 individual animals representing 370 some odd different species, ranging from corals and sponges all the way up to the sepulopods. Of course, fishes, you guys may have seen the harbor seals out there.

It takes a lot of care to keep this collection going. What surprises you most about your job? The thing that never fails to surprise me about this job, I would say more than anything, just how destructive animals can be and how much they can always lay your best plans to waste. You can never predict what a common day is going to be like here in the aquarium. And that's kind of the beauty of working in this field. As you learn something different every single day, and there's always a new challenge and a new opportunity.

You know, we've talked about cephalopods for years on end here, and we're always fascinated by the octopuses about how clever and smart they are. Tell us about how you've learned about that. That's a great example. Everybody knows cephalopods are smart, especially the octopods. They tend to be, in my opinion, anecdotally at least, the most intelligent of all the cephalopods. They can unlock these amazing prey puzzles. We saw some of the arms reaching in and grabbing a food item.

Everybody knows the classic experiment. An octopus can easily open a jar. I've even worked with some that can learn to discriminate sound. Now, they hear in a very low frequency, less than 20 hertz, which is 20 vibrations per second. But they can even discriminate the tune of a song slowed down to less than 20 hertz. know when it's time to feed. They can recognize their individual caretakers. So if I work with an animal every single day, that octopus will recognize me, even through the water as it looks up, when I come for feeding time. And if I'm off, if it's a holiday and somebody is filling in,

they'll actually recognize that, hey, that's not my caretaker, that's not my feeder. So certainly absolutely the most intelligent of all of the invertebrates, hands down. Wow. Now, Chris, tell us about this new species. of extinct? Genus and species, yes. And it had 10 arms. Is that correct? Because that's not something we have today on.

Well, we have 10 arms with squids and cuttlefish today, right? But the unique thing about this fossil is it's the oldest relative of octopuses, which, of course, by name, you know, all have eight arms. So the vampire squid is sort of a living fossil to understand. early octopuses, and they also have eight arms, but in addition to that, they have these two thin filaments. Those filaments have always been thought to be the vestigial remnants of an additional two arm pair, the same arms that we see in squids. But we've never had a fossil that could actually demonstrate that before. So this is a pretty exciting find to be able to prove something that we've

thought we've understood for a long time. Wow, and did you give it a name? Yeah, we named it Solipsimipodi by Denny. And how do you take that name apart? Why did you name it? So the genus, ellipsimipodi, that's, it means prehensile foot, which is because the arms of a cephalopod are modifications of the moluscum foot. So this is that organ you see at the bottom of a snail, right? It's the same structure there that you're seeing in cephalopod arms.

And prehensile, because in addition to having 10 arms, like you mentioned, This is also the oldest fossil we have to preserve suckers on those arms, which is pretty rare for a fossil. There's only a handful of those known, but this is the oldest. I'm wondering how you get a fossil if it's such squishy material to begin with. How does it get fossilized, you know? Yeah, so we have a lot of fossil cephalopods, but most of them, you're right, are the hard materials, the shells or the gladius,

which is this chitonous remnant of a shell. The soft tissues themselves, you only get in these exceptional localities, typically characterized by having no oxygen in the area for some short interval of time. So an animal swims into this deoxygenated zone, or the zone, you know, moves into the area where the animal is. They die, they suffocate, but also they can't be scavenged by any predators. And it's difficult for them to decompose because of the, lack of oxygen. So then they can settle down and if you have a very

gentle environment, you know, low current, fine-grained mud, not rocky, then the animal can lay there, get buried and you've got a fossil. Now Barrett, I know as I said before you helped write the animal care manual for giant pacific. Is octopuses and octopi? Same thing? Can you say it either way? Or is it Octopus. According to Merriam-Webster, you can use octopi. The traditional plural is octopuses. Technically, it's octopities because it derives from the Latin, not the Greek. Nobody says octopities. Only real nerds say that. After tonight everybody's going to be going home saying.

Octopuses, if you're referring to more than one animal of an octopus, could be multiple species. Or octopods, I like to use, if you're referring to multiple. different species within the order octopoda. Octopoda. Octopoda. Okay. Now, you write a manual. If I open up the chapters of your manual and octopoda care,

what am I going to see in there? What are some of the clues and the hints you'll tell me about taking care of the octopuses? So these things are amazing predators that have evolved metabolisms higher than anything else we keep in aquariums. The metabolism of an octopus is actually multiple times higher. than the most energetic fishes. Think mako sharks and albuquer tunas and all these marlin high-performance swimming machines. An octopus, the lowly common octopus,

has an order of magnitude higher metabolism than many of those species. So they got to eat a lot. We know that from the science. They have to eat a lot. They have to eat pure protein because they actually don't have the emulsifiers in their gut to absorb things like lipids and fats and oils. They can't take those in.

So they need a very lean protein. source and they need a whole lot of it, but also their water temperature. They have extremely sensitive water temperature requirements. Sepulopods in general are some of the, if not the most sensitive animals we keep in aquariums because their skin is what we call a microvillus epidermis. It's a single cell layer thick. So any contaminant in that water immediately gets transferred into their bloodstream. We have a pretty good integument. Our skin is pretty thick and good at keeping things out. Fishes have skin and scales. Octopus don't have that. So there's quite a bit in there about their behavior, but also their water quality needs, their temperature

requirements, and the nutritional requirements, and even cephalopod medicine. Yes, it is possible. There are veterinarians now that specialize in cephalopod medicine, and we know which drugs we can and cannot use on these animals. Can you take one home and make a pet? I will say absolutely, with the caveat, you can absolutely keep an octopus at home if you are a highly skilled aquarium and you know what you're getting into. These animals need a big amount of space compared to the size of the animal. They need very exact water quality requirements. So you need to be an accomplished saltwater reef keeper to start with. And they're very expensive. We heard about how fast they grow. Some young octopods can grow 5% of their body weight per day and they can eat twice that.

That's a big food bill. It's a huge food bill. What's their favorite food? So most octopods are going to feed predominantly on bivalves and crustaceans in the wild. So they're eating clams and they're eating crabs. About 60% for most species, 60% clam or bivalve diet, and about 40% of that is crustacean or crabs. Now, Chris, you spend a lot of time in what people refer to as the stacks in a museum, right? Yes. What do you do there? How exciting could that be going through the stacks?

For you, it must be very exciting. It can be exciting, yeah. It all depends what you're looking for. The most exciting drawers, as they say, are the ones that they are labeled unknown or, you know, cephalopoda in debt for indeterminate. So you just, when you visit a museum, if you're a paleontologist, most of the collections are behind the scenes. On display is maybe 1% or less of what the museum's holding. And they keep them there so people can do these types of evolutionary studies. If you want to understand how organisms are related to one another, you can use DNA,

but the other big piece of evidence you use is fossils. The problem with working on fossils is it takes a lot of time and a lot of study to become an expert in any one group. So this fossil that we talked about earlier, for example, that was sitting at the Royal Ontario Museum for about 30 years or so before somebody had happened to be me, but could have been any cephalopod expert, saw it and realized it was a different genus and species from something that had been described. Let me bring you back to that moment of discovery.

Here you are in the stacks. You're looking through fossils, and you say, oh, this looks different. Would that be an accurate way to describe it? That's about right, but it's always a little less glamorous than what you want to say. It's much more like you're looking through

a dozen or so drawers because I was a visiting researcher there deciding what you want to borrow. So it's much more mechanical. Like, oh, I don't know what that is. Let's set that aside. And I actually even myself sat on it for a couple years before doing anything

with this fossil. The real reason it ended up being a paper and a new species was because one day I happened to notice that it had those suction cups on the arms. And, you know, like I mentioned, that is very rare. So that's sort of provoked further study and further description.

But, yeah, you need sort of something to peak your interest. Lots of people have questions. Let's go to our first one. What's the difference between a octopus and a squid? What's the difference? I can take that. The easy difference is the number of arms. Squids always have 10 arms, octopuses, eight arms.

So if you can just count them, you can tell them apart. Next question, please. Hi, I'm Ava, and I was wondering, what does the word stuff upon mean? Yeah. So it means head, foot. I can't say exactly why it was given that name, but that's what it mean. And I think it's pretty appropriate, since they're the most intelligent mollusks by far, if you think of a clam, but also the most intelligent invertebrates.

You're listening to Science Friday from WNYC, Stu, I'm speaking with Barrett Christie and Chris Whalen about cephalopods. Next question over there. Do oxopuses see color differently? Whoa, good question. That's another excellent question. So octopuses have the same range of color that we see. So they can see all of the colors represented here in the room,

but they can't tell the colors apart. So functionally, yes, they are colorblind, but they're not like a lot of species that are colorblind. of species that are colorblind where they don't see red or they don't see blue at the other end of the spectrum. They can actually see all these colors. It just looks black and white. However, the super interesting thing is they also see polarized light, like you would see through polarized sunglasses. And we're seeing some recent literature, in past 10 years we're seeing some literature that the cuttlefishes and the squids can actually

communicate with each other using polarized light. So they can make patterns on their bodies and send a signal to each other like, hey, back off or, hey, I want to mate with you, that we can't even see with the naked eye. Only they can see it because it's only represented in polarized light. Okay, next question. Hi, I'm Valerie. I'm a science teacher from Woodbridge, Connecticut. And I'm curious about the relationship between the nautilus and the non-shelled cephalopods.

Is the nautilus the ancestor of the squid, the octopus, and the cuddled fish? And which one came first? Like when the shell, if the shell was discarded and we had evolution of these other fassas. Yeah. Yeah. Yeah. So all mollusks ancestrally have a shell, and that includes cephalopods. And most of the fossil record we have of these are their fossil shells.

This is an active debate. Nautilus split from other cephalopods at a minimum 400 million years ago, alternatively more like 500 million years ago. And this is an active debate. But those early relatives of squids and octopuses would have also had an extra. shell. And then around 380 million years ago, that external shell becomes internalized, more or less like your bones. And most cephalopods today still have either that internal shell or a remnant of that internal shell. So it is, Nautilus is a good way to understand what the ancestors of the other cephalopods look like, but it is not itself an ancestor of those

cephalopods, if that makes sense. And it has some unique characteristics that are just a nautoloid innovation, like the number of arms. If you look at a nautilus, they have something like 90 appendages. And that's not the ancestral condition. That is a unique innovation of that group of animals. 90 appendages. Something like that, yeah. I don't know the exact count. I don't know. That's close enough for government work. Next question. Hi, my name's Paul. Would you say that cephalopods are the smartest animals in the ocean or certainly one of them? Probably not the smartest animals in the ocean, but one of them. Because you've got to remember you've got dolphins in the ocean too, which are, I think,

usually considered the smartest animals besides primates. Yeah, I would say that they are by far the most intelligent invertebrate. But remember, whenever you hear people talk about cephalopods, you always hear that qualifier, invertebrate. There are far more fishes, dolphins, marine mammals that are just an order of magnitude more intelligent. You know, your dog at home, or even pigs, pigs are highly intelligent animals. Dogs and pigs are way more intelligent than cephalopods, which doesn't diminish how amazing they are. They're by far the most intelligent invertebrate, but they don't really rank up there with the dolphins. Wow. They're cooler than dolphins. They're cooler. They're just not more

intelligent. All right. I think we have set the record for the number of questions from the audience in a Science Friday segment. Thank you all. I want to thank our guest, Barrett Christie, Director of Animal Husbandry at the Maritime Aquarium here in Norwalk, Christopher Whalen, postdoctoral research, and inverterate paleontologist at the American Museum of Natural History in New York City.

Thank you both so much for being here this evening. And also thanks to our partners for tonight's events, Connecticut Public and the Maritime Aquarium. Thank you all here for taking time to be with us. And as we say on Science Friday, that's about all the time we have for today. If you missed any part of this program, you'd like to hear it again. Subscribe to our podcasts or ask your smart speaker to play Science Friday. You can say hi to us all week on social media, Facebook, Twitter, Instagram. Happy Sepulopod Week to everybody.

Have a great weekend. Vyra Flato.