Ancient Antarctica

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Antarctica as a cradle of life

0:30Antarctica. Today it's the frozen, snow-covered southern continent. But for hundreds of millions of years, it was a cradle of life, full of reefs and rivers, of trees and temperate climates. It was the linchpin of the ancient supercontinent known as Gondwana,

1:02that millions of years ago connected Antarctica with continents such as South America, Australia, Africa and India. Now, over the past century, paleontologists have uncovered some remarkable fossils from Antarctica, from trilobites and early invertebrates of the Cambrian period, get this, half a billion years ago, to ancient sharks of the Devonian almost 400 million years ago. They've also found evidence of dinosaurs, of early marsupials, and so much more.

Introduction to ancient Antarctica

1:35Welcome to the Ancients. I'm Tristan Hughes, your host, and this is the awesome story of ancient Antarctica. Our guest is Professor John Long. John is a paleontologist and world expert on early sharks and fossil fish, and he has been part of several expeditions to Antarctica over the years, discovering fossils in some of the most extreme locations on Earth. This was such a fun chat, and as you're about to hear, John's career, well, he's had quite the adventure.

2:08John, welcome back to the show. It's good to see you again, my friend. It's an absolute pleasure, Tristan. I love the show. Well, last year we did the first sharks and Megalodon. Once again, we're recording in the morning, my time in the UK. It's evening where you are. I've got a cup of tea. First things first, do you have a beer in hand as well? I've got a beer. Yep, it's beer o'clock here. Beer o'clock, fantastic. Tea and beer o'clock. As we delve into this cracking topic, Antarctica, okay, it's not rich in human archaeology and

2:42ancient civilizations, but it does have paleontology aplenty. Absolutely. I mean, it's a massive continent. You've got to think of the size of Antarctica. It's like one and a half times the size of Australia. It's about the same size as the continental United States. And it's mostly ice and rock and snow, but it doesn't have plants and soil. So where the rock sticks up, you get good exposure. It's great for finding fossils where you've got those mountains that stick up above the polar plateau. So just imagine

3:14a continent that the average height is 2.7 kilometers above sea level. That's the average height of Antarctica. So yeah, it's got a lot of rich paleontology, a lot of great pickings, a lot of fabulous fossils. And the power of the earth, I mean, you mentioned that some of those places, those rock faces are more than two kilometers high. To get a sense of the power of the earth over millions and millions of years, is it from that high up that sometimes you find marine creatures that were once living beneath the waves?

3:45Yes. The tops of the mountains are just whatever geological strata has been pushed up through the faulting. Think of Antarctica as the linchpin of this supercontinent called Gondwana, which was the largest continent of its time, you know, in occupying the south of planet earth. And you've got Gondwana is made of Antarctica, joined to Australia, joined to India, South America, Africa, you know, all in this one massive area. And Antarctica held it all together until it all

4:16started breaking up. So the paleontology of Antarctica is crucial to understand that quintessential origin of various animal groups that migrated from one part of the world to the other. You know, how do you find fossils, for example, in South America that also occur in Australia today? You know, that only Gondwana explains it.

Early fossil expeditions and Gondwana

4:38Gondwana, well, we'll get more into Gondwana in a bit. But I mean, John, how long ago was it first realized that Antarctica was rich in fossils, that it could be this haven for learning more about prehistoric life? Well, Tristan, it goes back at least to the 1890s with some of the Norwegian expeditions. Larsen, you know, and the whaling that was happening there. And the whalers and people that went down there would exchange their fossils for tobacco and trade it with the brandy and so on. Because they knew fossils were a good currency. People liked them as curiosities. But the

5:11serious collecting of fossils from down there really started with the scientific expeditions of the heroic age. Scott and Shackleton foremost amongst them. So as we all know, Scott went down there in the Discovery Expedition, 1904. And although they didn't get to the pole, they did collect some fossils on the way. But then Shackleton, who was on that expedition, ran his own trip back to Antarctica. And he came close to the pole. He came, you know, within a degree and a bit. And they

5:42collected some amazing fossils from the Beardsmore Glacial region. And they were the first ones to bring back fossils of Cambrian age, over 500 million years old. And what they found were the beginnings of what would be uncovered by later geologists as a gigantic reef that covered the entire of Antarctica 520 million years ago, called the Shackleton limestone. And it's made of sponges and algae and various creatures that formed the first great reef in the entire world.

6:13Wow. And on that expedition, the ill-fated one where Scott doesn't make it back. Is it true, John, that amongst the finds that were with Scott and his companions, you know, that were later discovered, that they also found out that they were bringing back more fossils with them at the same time? Yes. And it's quite sad, really. It's really tragic that towards the end of that expedition, as they knew they were running out of food and they were running out of supplies, and they kind of knew they weren't going to make it back at one stage, they were still dragging rocks with them right to the very end. So when they found their bodies inside the polar tent, you know,

6:47dead, there were rocks and specimens there and notebooks that kept precise records of where those specimens came from. And they would be intrinsically important for the concept of Gondwana because, you know, amongst those specimens were fossil plants and remains of the flora that spread right across the whole of Gondwana from Africa to India, Australia, South America. And the seeds of Gondwana

7:17were in those specimens for, you know, back in 1912 when they all died, but they brought those specimens back, the British Museum and the British Antarctic Survey and places like that. And they were eventually studied. And that's where the whole concept of Gondwana really originated from. That's so interesting because that's something I knew nothing about. You hear about the ill-fated expedition, you hear about the race with Amundsen and so on. You don't realise that that period of time is actually so critical for people realising how rich in fossils Antarctica was for learning about

Modern scientific expeditions to Antarctica

7:47the deep past. And John, over the 20th century, more and more expeditions, scientific expeditions have gone there to find out more. And as time went on, including yourself, you've been able to go there several times over the course of your career to look for fossils. Yeah, I've been very lucky, Tristan. I mean, I first went down there in 1988. Originally, I was at a conference in 1985 in New Zealand, and I met an amazing woman, Margaret Bradshaw. I dedicated one of my books to this woman. She won the polar medal from the Queen, actually, for her

8:18many expeditions to Antarctica, searching for fossil shells and trace fossils. So Margaret didn't have any experts in New Zealand on fossil fish, and that's my speciality, Devonian fishes. And they were mapping this vast area of the Devonian, the old-fashioned way with sledges, where you'd be dropped in by a Hercules aircraft, a remote part of the trans-Antarctic mountains. And then you'd have your sledges and your skadoos to pull them along. You'd put up a base camp, and you'd go out and work and then move along.

8:49And so she invited me to come down in 1988. That trip didn't work out the way it was planned. They were held up with storms and bad weather in the mountains. So I flew down to the base down there, Scott Base, in New Zealand. And basically, they couldn't actually get me out to those mountains. So I spent that whole month in the dry valleys and other places, but without Margaret's expedition. So we planned the whole thing again.

9:20And I went back again in 91-92. And that was, for me, the big expedition. We spent three months down there, sledging through virtually unknown territory. They'd been to one or two of these sites before, but we eventually made it to a whole area of the trans-Antarctic mountains that no one had ever mapped or studied before. And fossil sites were everywhere. Hazards were everywhere. Crevasses, avalanches. It was just one of the most spectacular and frightening things I've ever done in my life,

9:51because every day you're just blown away by the sheer beauty, the transcendental nature of these mountains that just poke up above the clouds as they're so magnificently tall. And then other days, you find yourself, you're in a crevasse field, and you have to sort of walk out slowly with a crevasse probe. You're prodding the earth in front of you like a minefield, you know, to get out. And every day was an adventure. So I kept a diary. And eventually, I wrote this up as an account of the dangers and also the highs of discovery of this whole expedition. It's amazing how, you know, still

10:25parts of our world, there is that proper sense of exploration and adventure. And I think fossil hunting in Antarctica really defines that. This is polar Indiana Jones, health and safety nightmare. You must have been, John. But we'll delve into a few more of those stories as we go along. One question I'd love to ask, though, is when you're looking for fossils, whether it's in a crevasse or on a rock ledge, how do you look for them? I guess it's more than just, there's no fossil metal detector equivalent where you can detect fossils beneath the ice. I mean, how do you extract and look for fossils in Antarctica in a place like that?

11:00Well, it's actually very easy, Tristan, because as I mentioned earlier, there's no soil or plants in Antarctica. It's just bare ice and bare rock. So fundamentally, when you come to a mountain range that sticks up above the polar plateau, you've got pure layers of clean rock. And if you're looking in sedimentary rock for fossils, all you don't want is those layers covered up by snow. So there've been recent snowfalls, the whole outcrop could be covered up by snow and you can't find anything.

11:30But the strong winds, especially the storms, the katabatic winds that accumulate by gravity flowing from the central part of Antarctica, which is much higher than the edges, you get these massive katabatic winds that cool the area, they blow the snow away. And you get sometimes just clean, pristine layers of rock bristling with fossils. And it's like a kidney candy shop. You don't know which one to dig up first, you know, or you've got limited time. Although 24 hours of daylight means

12:02you can go nuts. And some days we'd be up the top of the mountain working to a three o'clock in the morning in bright sunlight. And then we'd just get so tired, we'd have to go back to camp and sleep and eat. But yeah, it's another days we'd have storms where we'd be holed up for three or four days in our tents waiting for the storm to blow away. So it's this boom or bust kind of mentality when you're down there. It's easy to find the fossils because you don't have these blockages of plants or soil covering up the rock down there. But then you've got a hammer of them out with a hammer and chisel

12:35the old fashioned way. We don't have power tools down there, you know, in these remote locations. No, you say the old fashioned way, as you say, I mean, you're looking for the fossils just with your eyes, you know, with your expert eye, recognising them on the rock face. And yeah, as you say, just then using a hammer and chisel to get them out one by one by one, old fashioned, but it's how you do it down there. That's very cool. Yeah, we did it. And we can only carry a limited amount of fossils as well. So we had a system whereby we had a skidoo, Alpine skidoo, pulling two sledges. One would be just fuel, drums of fuel.

13:07The other would be our food and our supplies, our camping gear, etc. And as we ate the food, we'd get an empty box that we could fill with fossils and samples, but we couldn't carry any more or any less. So we were limited. By the end of that three month expedition, we had all the empty food boxes basically filled with our best fossil samples.

The supercontinent of Gondwana

13:27All right, well, now let's explore Antarctica itself back millions and millions and millions of years ago. And let's revisit that keyword you mentioned near the start, John, which is Gondwana. So set the scene for us. How long ago was Antarctica? How long ago was Antarctica formed? And how does that link centrally into this idea, this mass that is Gondwana? Well, Antarctica has always been part of this supercontinent of Gondwana. And when that formed, there are other parts of it, Rodinia before that. But fundamentally, it was locked into a

14:03major supercontinent from at least 550 million years ago or longer. And as Rodinia, this other mess of continents sort of broke away from Gondwana and it formed its core, then we have this supercontinent that stayed together virtually until about 50 to 38 million years ago when the last remnants of it broke away. And those last remnants were Australia and New Zealand joined to Antarctica. So the other big supercontinent like Africa, South America and India had broken off at different

14:37stages, mostly during the age of dinosaurs. They all started to break up and start drifting away. And then we're left with just Australia, Antarctica, New Zealand as this one landmass. And then Australia and New Zealand kind of break away together. And then New Zealand breaks away. And yeah, 38 million years ago is one of the estimates that we say was the last remnant of that Australian continent rifting away from Antarctica. And then the polar seas could form a current all the way around

15:08Antarctica for the first time. So before that time, so hundreds of millions of years ago, for instance, when you do have Gondwana as that supercontinent where Australia, New Zealand, parts of Africa, South America, even parts of Europe, if I'm not mistaken, are connected together to Antarctica as the linchpin, as you say, this southern continent of Gondwana. During that time, that southern continent is not always a tundra wasteland. The climate changed a lot in that time. Yeah, well, the interesting thing about Antarctica is it's mostly been for all of its life,

15:40a normal continent with, you know, once plants evolved and covered the land, Antarctica had a rich flora of plants from the very first forests on Earth. They were down there in Antarctica as well, with fishes in the rivers and amphibians eventually invading the lands, reptiles, dinosaurs, mammals, a whole lot. It's only the last, say, seven million years or so that Antarctica has become a frozen wasteland. And up until then, it's been just like another continent, like Africa or Australia

16:13even. So the fossil record in Antarctica, I appreciate there must still be so much to find for tens, many hundreds, if not thousands of years to come. But how far back currently does the record of fossils of life go in Antarctica?

The Cambrian limestone reefs

16:31Well, there are some microfossils found in protozoic rocks that could be over a billion years old. A billion, gosh. Over a billion. But they're just microscopic sort of fossils that have been found by dissolving the rocks up. But in terms of actual macro fossils, the real fossil record of Antarctica starts with this reef, the Shackleton limestone about 520 million years ago. And it's, you know, a whole host of trilobites, little bug-like creatures that live on the bottom of the sea, and shells and mollusks and things like that, corals, sponge-like cup-shaped things called

17:06archaeocyate athids that build this reef. Yeah. So that's the beginnings of the Antarctic fauna, if you like. But it's kind of, at the time, a sort of a global fauna in the Cambrian that we also get in Australia and Europe and North America and places like that, but with unique species to those regions. But, you know, a reef then would have looked the same as a reef in any continent of that age, basically. And the Cambrian period that you're describing, John, we did an episode not too long ago all about it. It's probably nicknamed Biology's Big Bang. So this time we see this great explosion

17:39of different life, of complex life. And you mentioned perhaps the most famous type of animal from it, the trilobites. Yes. And this idea, when you say a giant reef, should we be imagining, as you say, a reef today, maybe not the Great Barrier Reef, but full of life, shallow, teeming with life, and with Antarctica, would it be stretching on for hundreds of kilometres over and over and over? Absolutely. Maybe a thousand kilometres. I mean, it covered the whole of Antarctica from the east to the west. It was the first great reef on Earth, for God's sake. This is huge.

18:12I mean, you know, Antarctica is the beginning of these giant reefs forming that would later change in their construction, you know, eventually ending up with coral reefs today. But in the Devonian, they were built of other kinds of, you know, sponges and sponge-like algae and stuff. And reefs have changed all through time. But the first ones were these archaeo-ciathid reefs. They're like a sort of a hollow cup-like, sponge-like thing. And do we know much about the life that was there beyond the trilobites? If it was, you know, the first reef in the world and so massive, surely it must have been almost kind of the crucible

18:47for so much life during that time. That's true. But we've also got to remember that it wasn't unique to Antarctica. This Antarctic Reef was probably one of the biggest in the Cambrian, but we also get them in other parts of the world with diverse floral assemblages. But, you know, Antarctica's got a rich diversity of invertebrate life at that time. There's arthropods, there's remains of different kinds of mollusks and all sorts of creatures that lived in the sea at the time, but nothing gigantic or spectacular because

19:18creatures weren't that big on this Antarctic reef at the time. They were mostly small critters. And the type of rock that you look out for to identify that, okay, this is probably from Cambrian times. You mentioned that it's the Shackleton limestone. I mean, how common is it to find that type of rock layer, you know, when you're searching Antarctica today? Well, you've got to go to the far kind of east of Antarctica to get the outcrops of the Shackleton limestone. And these are places without any bases nearby. So you basically need a really big

19:51aeroplane like a C-130 Hercules, long range tanks to get there. We didn't go that far, but we did have a Hercules drop us off because we were so far away from the base that was beyond helicopter range. So it's kind of neat being in your own Hercules with just four people and your sledges to, you know, fly to a very remote part of Antarctica and then get spewed out the back of this thing. And then away you go for three months until they pick you up. But no, back to your question about the Shackleton limestone, because it has been eroding for so long, the original first pieces of it that

20:26Shackleton's expedition brought back were in glacial moraine, which means there are bits of rock that have been broken up and, you know, encapsulated within a glacier and then melted so they could find the rubble around that melt zone and pick up bits of this limestone, which originated on the other side of Antarctica. Wow. Okay. Once again, the shifts of the Earth, the movements of the Earth right there. It also sounds for you saying, John, if we were to do a documentary in the future about paleontology in Antarctica and we want to do episode one on the Cambrian, we would be going to the most remote

21:00parts possible to find those fossils. I love the fact that the oldest fossils, the macro fossils you have from Antarctica are almost, I know it's not the case that we'll explore, but from the outset, it seems the most difficult locations to reach. They are. Yeah. Those Eastern Antarctica areas are very hard to get to. Very few people have been there. And that's why, as you said, there's so much potential to find new things in Antarctica because, you know, like in terms of Devonian, the fishes I study, people only get there once every like

21:3120 or 30 years kind of thing.

The Devonian period and river deposits

21:34Well, you mentioned Devonian. So what do we mean by Devonian? How far forward are we going in time for this next key stage of life in Antarctica's story? All right. So the Transantarctic Mountains are made up of what's called the Beacon Supergroup, which packages of rocks of different ages. And they kind of range from, they start at the sort of the Silurian, perhaps, Devonian boundary about 420, 30 million years ago. And they go right through to what's called the Carboniferous or the Coal-Bearing Age. And then there's an unconformity

22:05and then you get more rocks, Permian, Triassic, Jurassic, et cetera. But that first package of Paleozoic rocks called the Beacon Supergroup ranges in age for over 150 million years. But the bulk of it, the thickest section of it is Devonian rocks, which come from Devon originally. That's where they were first named in the UK. But the Devonian, think of it as a big time period of rocks. It's like 60 million years of time. It started 420 million years ago, roughly, ended roughly 360 million

22:38years ago. But it changed the earth forever because before the Devonian, we had mostly jawless fish in the oceans, you know, a few spiny shark-like things. During the Devonian, it was the jawed fish that really took off and populated the oceans and rivers and lakes of the world, including sharks, armed, ancient, grotesque beasts called placoderms. Because you love the placoderms, John. I do. I love placoderms. They were gigantic predators. And also the first bony fish that had

23:08advanced forelimbs with proper bones to support arms and legs that would eventually take over land as early tetrapods or amphibians. But at the same time going on with that, we've got the invasion of land by insects and arthropods. And we've also got forests developing for the first time on earth. So instead of, you know, mosses and lichens covering the shores at the beginning of the Devonian, we've got forests over 30 meters high or 100 feet high by the end of the Devonian.

23:39And this is pumping lots of oxygen into the atmosphere, making insects get bigger and arthropods get gigantic and tetrapods able to breathe air on land. So that's all happened in the Devonian. It changed the earth forever and really was the heralding the modern world in terms of, you know, what would inhabit life on earth and in the oceans.

24:03So it's the Devonian, the first period you can see in the fossil record where you get a sense of, yes, we'll explore these sharks, this amazing marine life still beneath the waves, but also for the first time getting a sense of life on land as well. So we get a more kind of,

24:34dare I say, complete picture of Antarctica at that time. That's correct. Antarctica had these massive deposits of freshwater river deposits called the Aztec siltstone. And below that, it had some layers of shallow marine kind of older sediments that had lots of trace fossils and sometimes mollusks and things like that. But really this thick package called the Aztec siltstone is one of the richest deposits in the world for freshwater fishes of that age. You know, it's got something like up to 70 different species

25:05occurring in it and many sharks, many types of placoderms, bony fishes, even remains of jawless fishes. You know, so it's got a diverse assemblage that probably occurred over five or six slices of time, you know, where the formal assemblages change. And, you know, think of a gigantic rivers as big as the bloody Mississippi or the Nile, and they're depositing enough sediment that's burying these fish and you're getting the first really big fish on earth appearing in these river sediments,

25:40like placoderms and sharks that are up to maybe three to four meters in length and giant bony fishes with teeth, three inches long, you know, almost like half the size of a T-Rex tooth, eating these other big fish. So it was a really dynamic ecosystem. And John, at this time, so we still got Gondwana and Antarctica is the linchpin of this great southern continent. You've got Rodinia further north, but Antarctica at this time is temperate. It's good. It's full of rivers. It's full of large forests starting to emerge on the land as well.

26:14All of this diverse life and you get it surviving. You mentioned when we talk about the Cambrian that you had this particular type of rock, the Shackleton limestone, but you mentioned Aztec siltstone. Is this the type of rock you're now looking for wherever you go saying, if you find it, you're like, right, we're in the Devonian period. Yeah. So on our big expedition of 1991-92, we were tackling an area that had just discovered that there was Aztec siltstone there by an earlier geological party. And we were the first team

26:46of paleontologists to go in and actually explore those unknown mountains and basically collect fossils from that Aztec siltstone from a whole range of new sites, including mountains that hadn't been climbed before. We were the first people to climb some of these mountains like Mount Goodmanson. And I'll tell you a really interesting story, a parallel with H.P. Lovecraft. Now, do you know H.P. Lovecraft, the gothic horror story he wrote in 1931 called At the Mountains of Madness? I'm sorry, John, that's my lack of culture showing. I don't, but you can explain it.

27:18Explain it. All right. So this guy wrote the Dunwich Horror and the Amityville Horrors and things like this. He was one of the world's best classic horror novelists of the day. So he writes this story called At the Mountains of Madness, set about a fossil hunting expedition that flies down to Antarctica in the 1930s. They'd come on a boat, they'd bring planes, and then they'd go to the most remote part of Antarctica where there are mountains. And as they go further and further deeper into this unknown

27:49area, they uncover the elder ones, the alien ancient civilization that's been there, and they either all get eaten or go mad. Are you sure this isn't Alien vs. Predator? No, no, no, no. It's a wonderful book. It's only a novella called At the Mountains of Madness. Yes. So when I went down there on that trip in 1991, a good friend of mine that knew this book gave me a copy and said, here, take this and read it while you're in Antarctica. So we read a couple of pages aloud each night from that polar tense. There were four of us on that expedition.

28:22Margaret Bradshaw, whom I mentioned before, Freka Harmson, an American geologist who came from New Zealand originally. Brian State, our survival expert, and myself, also fish expert. So two guys, two women, two polar tents. We'd get them crammed into one tent. We'd read this aloud. We eventually discovered that we were heading to this place that Lovecraft put an imaginary longitude called the Mountains of Madness. But we were heading exactly to where he put this imaginary fake geographical point. So we named our

28:52mountains, the Mountains of Madness. As we got deeper and deeper into these Mountains of Madness that no one had ever really gone to before, the northern part of the Cook Mountains, we discover all these amazing sights and had all these amazing adventures. So when I wrote my book in 2002 called Mountains of Madness, it was a parallel story with H.P. Lovecraft as they sink into the doom and terror of internal Antarctica. We were experiencing our own emotional roller coaster as well as we went there. So one of the best locations in the world to find Devonian fossils,

29:28this age of prehistoric amazing fishes, the first drawed sharks and so on, is from a place that you and the team called the Mountains of Madness. We did indeed. And it was such a beautiful area as well, but slightly unpredictable in terms of weather and hazards because no one had been in there. They didn't have maps showing you where the crevasses were or where the dangers were. You just had to deal with it on a day-by-day basis. And what types of fish and life and on-land animals and fauna did you find at this particular location?

30:03We were finding a whole range of sharks for the first time that hadn't been found there before. Now, some earlier geological expeditions, 20 years before ours, had found some partially articulated sharks, you know, small things about up to, you know, half a metre long. But we were finding really large shark's teeth, quite big ones that were getting up to like 25 or 30 millimetres high. And this was really exciting for me because I realised that up until that point,

30:35most sharks known anywhere on Earth were really tiny, just from tiny little teeth. And suddenly there's this massive increase in sharks and also in freshwater. So it's, you know, the first major invasion of sharks into a freshwater environment, large river system. So these sharks would have been maybe three to four metres in length. And we were finding these, not just one, but several species of these sharks of different sizes from there. So that was very exciting. We found lots of new remains of bony fishes, early sort of ray fin fishes that were a bit like trout today.

31:10Lung fishes that breathe air with tetrapod-like fishes called tetrapodomorphs. Like, you know, you have this thing called osteolepus in the United Kingdom, these sorts of fishes. So it was very exciting. We just collected everything we could and brought it all back and then studied it and prepared it and processed it in the labs when we got back. But we named at least a dozen new species of ancient fishes from that expedition. Gosh, I love it. That part of the thing is you can name so much stuff, can't you, John? You have the power to name all of these species that you find and also these mountain ranges as well.

31:43It sounds like Aztec siltstone is more easy to find in the geology than the Shackleton layer, John. I mean, is it easier? And are there more ranges that you can go to and then easily spot, right, that is Devonian rock over there? Well, the Aztec siltstone was originally named from a type section that looked like an Aztec pyramid. But it has all these multicolored layers of red and green and yellow and gray colored rocks, which represent this ancient floodplain and river deposit.

32:15So you've got channels full of conglomerate or coarse sort of boulder type conglomerates. You've got mudstones that are red because they're oxidized and others that are anaerobic green, you know, mudstones as well. So all these colored layers of rock meant they were easy to spot from the air and to spot on a map with aerial photographs. So we knew that where we were heading, all we had were compasses and maps in those days. We didn't have GPSs or anything. But you could visually spot them through binoculars that over there, beyond that horizon, is a bit of Aztec siltstone.

32:51So let's go there and collect fossils. So I know you've been to many, many different sites and recorded many Devonian fossils from them. But I want to highlight a couple that I know have great stories around them. The first, just because I love the name, John, the Fish Hotel site. Oh, yes.

The Fish Hotel site

33:07I named that one. So what is this? Well, this is in a completely unexplored part of the mountains we reached on that expedition, the Northern Cook Mountains, very close to the Mountains of Madness of Lovecraft's location. And we just found these layers of rock packed full of impressions and bones of these Devonian fish. It's like actual bone beds with bones on top of bones, just packed full of, you know, thousands of pieces of bone everywhere. And so a lot of it was mushed up bits of bone, but occasionally you'd find more complete material and bits of skulls and things like that.

33:44So I noticed that every one of these beds forming this part of the Aztec siltstone was full of fish remains. So because all the beds were full, I said, let's call it Fish Hotel. And so you found placoderms there. Also this species, forgive me if I butcher the pronunciation, Bothriopolis. Bothriolipus, yes. Bothriolipus. Bothriolipus was the rat of the Devonian. They were like frigging everywhere. Every Devonian river deposit in the whole world has got Bothriolipus in it.

34:17Even in the UK, you've got about a dozen species from your deposits around Scotland and Northern England. But Gavin Young, one of my mentors who went down to Antarctica in 1971, 70-71 expedition, collected many Bothriolipuses and named something like a dozen species from Antarctica as well. And we found some more remains of material that could also represent new species. But we've never got around to describing them because they're so difficult, because they're so alike.

34:49They all look similar. You know what I mean? So you've got to be a real Bothriolipus expert within the Devonian fish world to name a new species of Bothriolipus.

34:59But there is an Antarctic version. That's good to hear. Yeah. So Antarctica at that time, full of life, these rivers, these lakes, all of these early sharks. We've explored the origins of sharks, the first sharks in our previous chat together, and a bit on the placoderms, the armoured fish as well. But there is one particular shark that you have discovered from Antarctica that is almost the Meg of the Devonian. So, John, what is this shark that you discovered at a place that I know is close to your heart called The Portal?

Discovering giant Devonian sharks

35:32Yes.

Discovering giant Devonian sharks

35:33Well, The Portal is, yeah, a very emotional place for me to even recall talking about it. It was on that expedition that had been snowing for 10 days, and we had this massive push. We were holed up for about 10 or 11 days, not being able to move anywhere, and it was near Christmas, and we'd left all our food and everything in another depot. So we were slowly running out of food and not being able to get back to our depot, and things got really, really lean around Christmas that year.

36:05Like, we didn't have much to eat. We had just little bits of – we had one miniature bottle of scotch that we shared around all four people for Christmas Day. But eventually, the weather cleared, and we did this massive push to The Portal, about 60 kilometres of sledging all day. You know, we get there, we set up camp, and the next day, I wanted to go out searching this mountain where 20 years earlier, Gavin Young had found one or two interesting shark's teeth, but no one had been properly collecting there. And I said to the leader of the expedition, Margaret Bradshaw, can I go out by myself?

36:40I just want to go out and get to this mountain and look at some fossils. They were all exhausted from the big push the day before, and it was lightly snowing, and they said, no, we're going to rest, but you can go out. Just take it easy. You know, you've been down here on two months already. You know how to handle yourself. So I set off with a full backpack, lots of food, radio, water, you know, in thermoses, equipment, rock, hammers, everything. And as I was walking away from the camp, I noticed that the snow got thicker and thicker.

37:11It was almost up to my waist. And then eventually, I felt a hollow, and I sort of broke through a crevasse, and I thrashed to one side, and it basically got away from the crevasse. But I was on my side, deep in the snow. I got up, and I looked back, and there's virtually a bottomless hole there where I just broke through a crevasse, but I was able to thrash to one side. Anyway, I was very shaken by that, but I basically very cautiously and carefully, step by step, got onto the first ledges of rock on the portal, and I started looking for fossils.

37:48And I realized it had been snowing so heavily for the last 10 days that there was a huge buildup of snow right up the scalp. And eventually, I got to a ledge where I was looking for fossils with my head down, and I saw bits of snow whizzing past me. I looked up, and there was this wall of snow coming down at me, like in a small avalanche. It hit me and knocked me over and buried me up to my neck, which was kind of comical, but also scary at the time. And anyway, it's very emotional. I cried.

38:18I let myself. My emotions overran me a bit at the time. I eventually pulled myself together, got up onto the ledge, and found some really good fossils, these big teeth of portalotus, this giant shark that I would later call portalotus. And I made my way back to camp, tracing my footsteps, but going wide around the crevasse, told everyone what happened, and they gave me a medicinal whiskey or two, and I slept. But the next day, we decided we'd get onto that mountain to collect more fossils.

38:49So we have a survival expert, Brian State, who basically grabbed a crevasse probe, and then he traced my footsteps step by step so we could find a safe access route onto that mountain. And he found, in tracing my footsteps, that I'd actually walked over seven crevasses, and I'd only broken through one. So we had to find a completely wider route back to the campsite after that. We did get some good fossils, and I eventually named that giant shark portalotus Bradshaw Eye after Margaret Bradshaw, and I named it other species after everyone on the expedition.

39:23But yeah, still to this day, it's a very scary place for me to recall. It took me eight years before I wrote down these memoirs and wrote this book up. But yeah, it was probably the closest I've ever come to losing my life, and I ride a motorbike too. John, I'm sorry to bring up that memory because I know it's obviously still very shocking, especially recounting it. And I think it also does harken back to, as cool and as fascinating and as extraordinary this chat is, and kind of this exploration that's still going on with fossils down there.

39:55It's still unknown territory. It is still, you know, very, very dangerous to find these fossils. And no doubt there have been accidents in the past, and there unfortunately probably will be in the future. But it is quite something that, you know, tied to that story, John, is the discovery of one of the biggest, if not the biggest, prehistoric shark from the Devonian period. Absolutely. I mean, at the point when we described this shark, and I named it, I worked with Gavin Young, who had been there 20 years earlier. We wrote the paper up together.

40:28Portalotus was the biggest shark known from the Devonian at that time. Nothing had a tooth anywhere near as, like an inch high or 30 millimeters high. So it was a big shark, and it was the biggest predator in that ecosystem of the time. Gosh. You know, in recent years, they're starting to find remains of very big sharks from other parts of the world, Morocco and Northern America as well. But they have not been published yet. I'm just saying. So at this moment, as we're speaking, it is still the largest known shark from the Devonian, full stop.

41:02Gosh. It's a certainty, surely, isn't it? That more extraordinary new species of fish, of sharks, of early life from the Devonian will be uncovered from Aztec siltstone layers in Antarctica in the future. It feels almost a certainty, right? Yeah. And, you know, after that big expedition of 1991-92, I've been privileged to go back on two more expeditions quite recently, like 2016-17, 2018-19 with Professor Neil Shubin of the University of Chicago and his team.

41:33And we didn't go back to the portal, but we explored a lot of the earliest sites in the Aztec siltstone where geologists, not paleontologists, had found fragments of fish, but no paleontologists had been back to those sites. And we quarried some of these sites and found beautiful, complete skulls of new species of stem tetrapod fish, fish that would give rise to the first land animals. A lot more placoderms, a lot more rayfin fishes, like early trout-like fishes.

42:03So we've got a bunch of new stuff that we're currently writing up that we haven't even published yet from those sites as well. So, yes, as you're saying, Tristan, it goes without saying that if any paleontologist that's trained in these sort of fishes can get back to those sites, they will find more material. Absolutely. We just walk around and we find layers and we dig into them and eventually you see bits of bone on the ground everywhere. You know you're close to a bone bed layer where you can actually find sometimes whole, complete fish, not just fragments or teeth, but articulated, complete fish as well.

42:37It's an amazing environment to find fossils in. Well, you mentioned animals there, John. So let's move on from the Devonian. And what's the next kind of part of ancient prehistoric Antarctica story where we see Antarctica once again teeming in life? What's the next big stage of prehistoric life in Antarctica following the Devonian?

Triassic dinosaurs and later fossils

42:59Well, I think we have to jump to the Triassic period. The dinosaurs, okay. That's 252 to 201 million years ago. And this is the time when the first dinosaurs, the first mammals, the first crocodilians, the first pterosaurs, flying reptiles, all appeared at the same time. But from American expeditions there back in the 1990s, they collected the first dinosaur, theropod dinosaur called Cryolophosaurus. But they're also finding remains of mammal-like reptiles or early mammals as well that would define the gondwan and fauna, such as the thing, a pig-like mammal-like reptile called Lystrosaurus, which is known from Africa.

43:40It's known from India. Parts of it are found in Australia, South America. And so these initial finds were cementing the concept of gondwana more so than just the plants to find animals that could actually walk from one part of the continent to the other. These are not things that can swim across oceans. So it adds to the sort of the fact that this is universal gondwana fauna that covered all these continents. And you're also finding them in Antarctica as well.

44:12So I've got so many questions from that. First of all, John, the big time jump we've done while we've gone from the Devonian to the beginning of the dinosaurs, the Triassic, so we've kind of gone over periods like the Carboniferous and the Permian. Why is that? Why does there seem to be an absence of fossils from those, you know, tens of millions of years, those big time periods? Well, we do have some Carboniferous coal measures that have some plant remains, but not much else. And then there's a sort of a gap in the fossil, in the sedimentological record.

44:43There are some Permian plants found in Antarctica, and there's a good flora of these different kinds of plants. But I'm just jumping to where we have the first sort of animal remains, you know, to keep on time, if you like. Fair enough, fair enough. And you mentioned the dinosaur there.

45:02I'm not going to pronounce the name because I've forgotten it. But what is this type of dinosaur that we have? Well, this is a meat-eating dinosaur. It's a bit like Allosaurus, which is a smaller version of T-Rex. But it's a funky Elvis Presley kind of dinosaur because it has these big wavy crests above its eyes, a bit like Elvis' sweatback hair. And it's called Cryolophosaurus. So it was probably about seven or eight metres in length that's owned from a fairly complete skull and partial skeleton from the top of Mount Fitzpatrick, which is about four kilometres high.

45:34So when Bill Hammer and his team from Augustana College collected it back in the 90s, the helicopter pilots were really frightened to even take a helicopter up that high. You know, it was really dangerous to get the air so thin up there. They did eventually get a helicopter up there and then they had to load it up. And, of course, coming down is a lot easier with a payload. But they collected these blocks of rock. They had the dinosaurs and mammal remains and amphibian remains. So they got quite an interesting fauna of animals that lived about 230 million years ago from Antarctica.

46:10And that period as well, you mentioned Lystrosaurus already. Another good friend of the show, Henry G., has described as a mix between a can opener, a pig and a golden retriever. I know Henry well and I've got a golden retriever too. But they are also, yes, they're not the big kind of carnivores. They're not like a cryolophosaurus or anything like that. But they're also one of the big survivors. And is there even potential that they even hibernated as well? It is, yes. So there's one theory about Lystrosaurus, that they lived in burrows.

46:42Yeah, it's not my area of expertise, Lystrosaurus, but I just know the remains have been found there and been described. All right, John, let's go on to the dinosaurs. So you've got that big carnivore, that Allosaurus-like dinosaur. But what other dinosaurs have been discovered from Antarctica? Well, they had some long-necked plant eaters called platyosaurs there as well. That's known from some isolated remains. And that's basically all we've got from that Triassic deposit and some remains of pterosaurs or flying reptiles, you know, bat-like reptiles called pterosaurs.

47:13But we've got to go then jump into the late Jurassic and early Cretaceous and late Cretaceous, which take us from 200 million years ago, the end of the Triassic, to about 150 million years ago in the late Jurassic, and then to about 80, 90 million years ago in the late Cretaceous, where we get other assemblages of dinosaurs and land animals on Antarctica. But these are more on the islands, Seymour Island, James Ross Island, on the other side of Antarctica from where I was working around the Ross Sea.

47:46So these have produced amazing deposits with not only dinosaurs, but marine reptiles, sharks, lots of plants, lots of shells, you know, rich deposits that recreate an age of dinosaurs in Antarctica. And some of these discoveries, although the first ones were made back in the late 80s and early 90s, quite recently, a bone was found in the geological collections of the British Antarctic Survey that showed they had a long-necked sauropod dinosaur, you know, like a brontosaurus type of thing, that was actually found in 1985.

48:22And they didn't know they had it until this year, 2026. So that's why the news story has broken this year. Yes, it was big, wasn't it? But it just shows the value of collections, whether they be in museums or geological surveys, that geologists go out, they collect what they see, they put it in the collection. And no one might see that or know about it for years, for decades even, but it's still there. And then you realize, wow, we've got this dinosaur that lived in Antarctica we didn't even know about. It's fantastic.

48:52A titanosaur, which is a group found in South America and also Australia. Our sauropods are dominated by these titanosaurs, whereas in North America and England, you've got other kinds that are more typical, like brontosaurus, diplodocus type of dinosaurs. And they're just walking from, as you say, from where South America is all the way to Australia.

49:31They're connected to the land bridge. Antarctica is still that linchpin, as you said earlier. And that brings me nicely into that next kind of type of animal, which is very recognizable to you in Australia, which are marsupials. Do we have dinosaur-age marsupial discoveries in Antarctica? Well, they're not kind of the age of dinosaurs. They're a little younger, actually. They're in the layers above. They're the Eocene deposits. But, yes, we do have marsupials. We have Antarctodolops and some other possum-like remains of marsupials found, again, by American researchers, Judd Case and Michael Woodburn.

50:08And that's really interesting. It's almost like what you'd predict to find there, knowing that Australia is rich in marsupials. And Antarctica is the neighbor of Australia locked into Gondwana, whereas the Northern Hemisphere continent is separate, where the placental mammals are abundant, you know, the mammals that give birth to live young. So the interesting thing is that sometimes Antarctica proves a point, even when the fossils don't come from Antarctica. So Australia has platypuses, right, and we have echidnas, we have monotremes, the only egg-laying mammals on the planet.

50:42And they're meant to be really archaic. You know, we have fossil remains of some of their jaws and teeth from Victoria, where I am now in Australia, southern Australia, that date back 120 million years. But recently, you know, the last couple of decades, they found a tooth of a platypus, get this, in South America. And they called it, the name of it is called Sudamericana, means South American creature, you know. And so we've got them in Australia, we've got them in South America.

51:14How can you explain that logically? And the only way is that they must have transgressed across Antarctica to get to those two extremes, when then the continents broke away. And you've got populations of platypuses living in South America 60 million years ago, and in Australia from like 120 million years ago, and they're still living there today. So that predicts that we will find them in Antarctica one day if we keep looking. John, it's really exciting. I could ask so many more questions. I've got things here on my notes, like the earliest modern bird found from Antarctica too, plesiosaurs in the seas.

51:49Following the dinosaurs, you mentioned those marsupials already, and earlier how Antarctica is still linked to Australia and South America for a bit of time. In those tens of millions of years after the dinosaurs, I'm just going to do a quick kind of, let's do a quick fire round. I'm going to put animals your way, like yes or no, whether they were there. Prehistoric penguins? Yes, gigantic penguins up to 1.7 metres tall. Wow. Prehistoric dolphins? Yes, about 3.5 million years ago, we had dolphins in Antarctica, Australodolphus, because Pliocene, 3.5 million years ago, was about 2.5 to 3 degrees warmer in the seas.

52:29But today, it's too cold for them to go down that far. So they were there a bit prehistoric whales. Yes, we had this giant filter-feeding whale called Linocetus. It had teeth, but early filter-feeding whales still had teeth on their jaws as they were developing baleen, and that lived about 35 million years ago. And it served from a whole, complete skull. It's a beautiful specimen. Well, there you go. I mean, you could ask so much more. To finish it off, John, when does Antarctica, in millions of years, when does it become the isolated, frozen world that we know it today?

53:04When does that kind of that final age of great diversity of life in Antarctica come to an end? Well, it starts splitting away from Australia about 50 million years ago, and by about 38 million years ago, that break is there. And so suddenly, we go from paradise full of life to polar ice full of death. Oh, very nice. And basically, the circumantarctic current is the death knell for Antarctica, because then there's no more warmer currents coming down from the north around a bigger landmass. So as a smaller southern landmass, it's completely engulfed by cold polar currents.

53:39It gets colder and colder and colder. And about 7 million years ago, the very last forests in Antarctica die. And after that, that's it. So only animals can get down there, like whales or fishes that live in the sea and so on, that can survive in Antarctica, and some seabirds, of course. John, this has been such an amazing conversation. I know we could have explored so many more sites that you've visited, especially focusing on that age of fishes, the Devonian. But it is such an amazing, a unique, you know, the only place in the world, this continent, this tundra wasteland continent, that is so rich in paleontology.

54:17And there must be so many more discoveries waiting to be found there in the many, many years ahead. There will be, absolutely, Tristan. As long as governments can still support Antarctic science, and that is the really big question. It's expensive and it takes a lot of logistics and planning to get people down to Antarctica and then get out to these remote places to look for fossils. As long as people still value the knowledge that paleontology can bring to society today, then hopefully they'll still keep funding expeditions to go down there. Well, John, I've loved this and I've loved all the stories you tell.

54:50You're a brilliant storyteller and you've got so many more stories still to tell us, which we're going to be exploring in a special bonus episode that we're recording right after this one, putting the spotlight on you and your amazing career. But that's to come very soon. John, last but certainly not least, you have written several books on Antarctica, they are called, and on fish, on sharks, they are called? Yeah, well, there's the shark book, of course, The Secret History of Sharks, talks about Antarctic sharks. There's Mountains of Madness, A Journey Through Antarctica, or the U.S. copy is A Scientist's Odyssey Through Antarctica.

55:23This is all about my expedition, exploits and adventures. It's out of print now, but you can get it online. But basically, the book on the paleontology of Antarctica, a popular book called Frozen in Time by Jeff Stilwell and John Long, is available through CSIO Press Australia, came out in 2011. Brilliant. John, it just goes for me to say thank you so much for taking the time to come back on the show. My pleasure. It's always fun talking to you, Tristan.

55:51Thanks so much for joining us today on The Ancients. I hope you enjoyed that awesome episode on Ancient Antarctica with Professor John Long. Now you can hear more from John on The Ancients. We recorded two episodes with him last year, one on the first sharks. That was quite the topic. And another on the biggest shark of all time, the real-life Meg, the Megalodon. We'll put links to those episodes in the show notes. And if you're a subscriber, well, we've also got a special extra episode with John, where we shone the light on John's amazing career, full of great stories of John coming to the Natural History Museum in London,

56:32then going back to Australia and really advancing the field and cooperative paleontology with First Nations communities and so much more. It is an amazing story, which we cover with John on our bonus episode of After Ancients with him. So if you're a subscriber, you can check that out. If you'd like to listen to that episode and you're not a subscriber, well, you can join up. You can sign up and become part of The Ancients team. We'd love to have you on board. Now, please make sure to follow the show on Spotify or wherever you get your podcasts.

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