Host: Benjamin Thompson
Hi, Benjamin here. Welcome to the Nature Podcast. As we feel our way into the new year, we’re going to repeat something we did this time last year, and that is to take a bit of a dive into some of the stories that have appeared in the Nature Briefing over the past days and weeks. And joining me once again to do so are Noah Baker. Noah, welcome.
Noah Baker
Thank you very much. Lovely to be here, as ever.
Host: Benjamin Thompson
And senior editor of the Nature Briefing and a voice that will be familiar to many people who listen to the Nature Podcast, and that is, of course, Flora Graham. Flora, thanks for stopping by.
Flora Graham
My pleasure. Happy new year.
Host: Benjamin Thompson
Well, we’ve got a few stories that we’re going to cover in this show and, Flora, you’re going up first, and we’ll begin with a significant story and a timely one, and that is the climate pledges of Brazil’s new president Luiz Inácio Lula da Silva, or Lula as he’s commonly known.
Flora Graham
Yeah, this is an election that of course was followed by scientists around the globe because the leadership of Brazil holds in their hands one of the biggest sinks of global carbon emissions in the world, not to mention global biodiversity, which is the Brazilian Amazon, and the new president made a lot of environmental-based promises while running, and I think that his win is seen by many as a hopeful step forward to maybe make some changes to the legislative priorities of his predecessor Jair Bolsonaro.
Noah Baker
I have to say, all of my Brazilian friends were watching this long run-off election that ended up happening so closely, and I was interested to talk to them, many of which aren’t scientists, about how much of this is about climate change. And a lot of the concern was about climate change and about the Amazon because there’s also just a lot of love for the Amazon within the Brazilian people as well, and it was being decimated under Bolsonaro.
Flora Graham
Yeah, deforestation of the Amazon reached its highest level since 2008 under the last administration. But it goes beyond climate, of course, into the wellbeing of this huge biodiversity sector – an area that we’re all thinking of because of the recent meeting that happened in Montreal, which we’re calling COP15, if you’re not overwhelmed by COPs. But immediately in his first week, he’s brought back in the ban on small-scale gold mining, which can really decimate the land that it affects, and you can see pictures in our article about these legislative moves. But another thing that Lula has done that I think is really important is he’s looking to establish an office which is devoted to exploiting the Amazon in a way that can benefit people in Brazil without using heavy, environmentally damaging techniques, and it’s actually within the Ministry of Science in Brazil, and that’s being seen by many as a real indication that he’s turning policy towards a more science-based approach.
Noah Baker
Which is very much in contrast to what Bolsonaro did, which was actually very much to strip science out of the administration.
Flora Graham
And scientific funding was part of that as well. I mean, scientists in Brazil have really been grappling with severe cuts to science funding, and that’s an area where scientists are still looking to see whether some of the promises that Lula has made will come to pass. I mean, his path will not be easy. There are representatives in Congress who do not support his policy initiatives, so he will have to make his own alliances in order to get this legislation through the Brazilian Congress.
Host: Benjamin Thompson
And Flora, you and I spoke when you were at COP27, speaking of all the different COP acronyms, and that was the climate change COP, shortly after Lula had been elected. Did you get a sense from people you meet there or spoke to about how they were feeling about the future?
Flora Graham
It was an amazing contrast because, both at this past COP in Egypt and the previous year’s in Glasgow, Brazil was one of the biggest representatives, and certainly they had a beautiful, flashy, glamorous stand with lots of amazing kind of interactive lights you could play with and things like that. Whereas the previous one in Glasgow, this was seen as the kind of ultimate example of greenwashing of an administration that had made very clear through its policies that it was not supporting the international agreement to try to agree the Paris climate change goals. Now, it was seen, even though Lula of course hadn’t come to power yet – he didn’t take office until the beginning of this year – it was a celebratory feeling. I mean, as you can imagine, most of the people at COP are there because they’re absolutely passionate about reaching the Paris targets, so they were very much aligned in that goal. There was really this feeling that they just could not wait to move forward with so much of this hard work and undoing so much of this damage as much as possible. That being said, I did talk to some representatives from Brazil who said it was actually a little bit difficult to be under the pressure of the spotlight and be the focus of everybody’s hopes and dreams because everybody knows it’s easy to make promises. It’s much, much harder to make those promises stick.
Noah Baker
Indeed, it feels very reminiscent of the switch from Trump to Biden, right? There's a very swift change of agenda, but that doesn't mean just because you've got a switch at the top, you have an easy path through to making change from a policy perspective.
Flora Graham
From the outside perspective of the global research community and the community of climate scientists and activists, it definitely feels like the loss of Donald Trump in the US. And there are more parallels, sadly, in that there were huge anti-Lula riots in Brazil just recently, which brought to mind similar attacks on the Capitol in the United States. So, in no way is this going to be smooth sailing, and I think everybody's kind of got fingers and toes crossed that the outcomes are as positive as possible for the people of Brazil and as positive as possible for the global community who relies so much on the decisions that get made there.
Noah Baker
And of course, as people are watching the Amazon thinking about climate change moving forward, thinking about the size of the carbon sink, there will also be a lot of attention paid to the people that live in the Amazon, the Indigenous people that live in Brazil. There are millions of them, and they were not particularly well supported. In fact, they were actively attacked under the Bolsonaro administration, so people will be looking to see what happens under a Lula presidency.
Host: Benjamin Thompson
Agreed, definitely one to keep an eye on there, both for the country itself and for the wider world of course. Well, let's move on in this roundup of recent Briefing stories. And I said that this was the second time we've done this, and the last time we all met to have a chat at this time of year, I talked about ichthyosaurs, right. These are extinct marine reptiles that live kind of contemporaneously with the dinosaurs but weren't dinosaurs. And I'm going to try and keep the streak going, right, because here we are, a year later, and I've got another ichthyosaur story. And this is something I read about in Science News, and it's based on a paper in Current Biology, and it's given some insights into, well, a rather unusual ichthyosaur graveyard.
Noah Baker
I love that we're distinguishing between usual and unusual graveyards because I've seen so many ichthyosaur graveyards in my time. I mean, the obvious question I want to ask first is what was unusual about this ichthyosaur graveyard?
Host: Benjamin Thompson
Well, it's the fact that there are so many of them, I think, is kind of what's going on here. So, let me set the scene then. So, in Nevada, outside an abandoned gold mining town, there is this pretty famous park, right, called the Berlin-Ichthyosaur State Park, okay, and there's lots of, well, as you might imagine, ichthyosaur fossils there, right, but all of one type – Shonisaurus – and I beg your pardon if I'm not pronouncing that quite correctly, right. And this is one of the largest ichthyosaurs discovered, like 15 metres long, like as long as a bus. And these bones have been found all over this area. But since the 50s, there's one area that has been of particular interest to scientists, where they found seven of these fossils in very, very close proximity, and they were all kind of in rocks that date back to about 225 million years. But it turns out there’s other little areas around there where there’s collections of these fossils. And it's kind of had scientists stumped for quite a long time, right? Why are there so many of them? I think, maybe up to 100, I think, have been found so far. And why is it only them? They haven't found any other marine vertebrates, so no obvious prey for them to eat. And until this paper came out, it seemed that there were only adults there as well. But a little bit of light has been shone on this now.
Noah Baker
So, you've got a giant collection of many, many of these ichthyosaurs with no prey. And so, the scientists are trying to work out why on Earth all these adults without the young’uns were getting together for an adult party.
Flora Graham
But it turns out it’s not just adults, is it?
Host: Benjamin Thompson
Well, that’s absolutely right, Flora. And it turns out the key to this puzzle actually was that some other fossils were there, right. But in this case, they'd been put in museums and not really catalogued, or they hadn't been discovered yet. And these fossils were embryonic and newborn ichthyosaurs of this same type. And so, we've now got the adults and we've now got these tiny, tiny newborns. And so, the researchers have come to the conclusion that this was potentially a birthing ground for these giant marine reptiles, okay, because this area in Nevada now is obviously a desert, but it was under a pretty deep ocean at the time, and this kind of fits in with the behaviour seen now in modern kinds of marine animals in some cases. Whales, for example, will migrate from one area to another – maybe an area with lots of food to an area where there's no food, which would explain the complete lack of other marine fossils. Or maybe the ichthyosaurs have gone there because there are fewer predators to eat these babies as they're born and kind of swimming around. It's a potential explanation for this puzzle that’s had researchers scratching their heads for decades.
Flora Graham
And ichthyosaurs are such handsome sounding animals. As Noah mentioned last year, they’ve got big chubby bodies and kind of googly eyes and they're kind of like funny dolphins and to imagine these gigantic creatures 230 million years ago taking themselves off to the birthing grounds to give birth to their babies, maybe something like the Baja Peninsula is now with grey whales. It's just a lovely thought that does make you feel kind of more connected to what was happening all that time back then.
Noah Baker
I was going to say the same thing. I remember going to the Baja Peninsula to go and see the whales there and it was fascinating, this kind of strange dead zone where there's almost nothing that lives but it's very warm and comfortable and calm. And it's a great place to raise babies so long as you don’t want eat anything.
Host: Benjamin Thompson
And it shows that potentially this sort of behaviour is hundreds of millions of years old. But I will say that, while they may have kind of solved this part of the mystery, there are a multitude of other questions as well, right? So, we have adult ichthyosaurs, we have baby ichthyosaurs. Where are the juveniles? Where are the ones in between? They didn't find any of those so far. And also, I guess the big question on top of all of that is, why did they all die at the same time and in the same place? And this is the thing that there's been speculation about for a long time – toxic algae, volcanoes. That was ruled out by these researchers looking at trace minerals and the rocks and what have you. A mass beaching like you might see with whales these days? But no, this is quite a deep ocean. There were no shallows there. But given that there's these different clusters, right, in this area shows that this has happened more than once.
Noah Baker
It’s really fascinating, though, to find this sort of preserved moment in time because these fossils appeared to be in the same strata. And it shows just how lucky you have to be to capture these moments in history because not only do you need these moments to happen in an area where fossilisation can happen, but also quite often, things need to all die very quickly, very suddenly, in a catastrophic event in order for us to be able to understand these kinds of behaviours. It's a rare find and I can imagine there's going to be an awful lot more that will be investigated in this particular area as they look for more examples of this kind of behaviour.
Host: Benjamin Thompson
Oh, 100%. And it may be that it wasn't a catastrophic event at all. Maybe this is just part of the ichthyosaur’s lifecycle that we don't understand just yet because there's so much that we don't know about these animals, right? Like they all went extinct before the dinosaurs did. Nobody knows why. I'm looking forward to this time next year when hopefully we can have our third instalment of ichthyosaur chat, and maybe some of these big questions will be answered.
Flora Graham
Welcome to ichthyosaurs-cast – your all-ichthyosaur podcast, only one episode a year.
Host: Benjamin Thompson
Hey, and what an episode it is. Anyway, let’s move on. We’ve got a few more stories to talk about today. Noah, why don’t you go next? What have you got for us?
Noah Baker
Well, I have two stories. But the first one, I’m going to continue with the cool animal story. But these ones are not extinct animals. They are, in fact, glass frogs. Have you seen these things before, these fascinating looking sort of transparent creatures that live in South and Central America?
Host: Benjamin Thompson
My nan has some glass frogs, but they were just terrible ornaments that lived on the side. I’m guessing they’re not the same thing, right?
Noah Baker
I briefly got very excited that your nan had like the most amazingly cool pets. Yeah, so glass frogs, they live in Central and South America in the rainforest, and they have this fascinating characteristic that their bodies are almost entirely transparent. Now, the reason they have these transparent bodies is to help protect them from predators, specifically predators looking up into the leaves. If they're sitting on a leaf and there's light shining down through the leaf, you don't want to see a shadow of your body. But if you make your body transparent then it's harder to see the outline, it's harder to see that you're there and it means that you can be more safe. Now, the problem with having a transparent body is that you have insides. So, you can make your skin transparent. Scientists have said that’s a relatively simple evolutionarily to do. You just get rid of all the pigment in your skin and you end up with kind of a see-through skin. However, things inside your body are much trickier. So, right now, with a glass frog, you’ll see organs, you'll see skeletons, for example. And the thing that really particularly could give them away is their own blood. There's a wonderful line in the story that I read in The Atlantic which is about a paper that was in Science that says that the glass frogs’ blood betrays them. And the reason their blood betrays them is because blood contains haemoglobin and that is a pigment that is necessary to ferry oxygen around your body and you can't get rid of that pigment because then you wouldn't be able to get any oxygen anymore. So, there's only so far you can evolve away pigment. However, the glass frogs have got a new trick that has just been discovered by researchers, which is genuinely baffling.
Host: Benjamin Thompson
I really want to know what it is, like you've set that up so beautifully, Noah. Right, so, how do they make their blood invisible, which they can't do apparently?
Noah Baker
Yeah, so, it’s true. They can't make their blood invisible. But glass frogs are active during the night when there isn't a particular risk from predators that might seek them with their eyesight. During the day is when they're at risk, and so what they do is, instead of making their blood invisible, they hide it. What they do is they take almost 90% of their pigmented red blood cells and hide them in their liver. They squish them all into their liver for 12 hours whilst they sleep during the day, which makes the amount of red blood cells that you can see in their bodies drastically fall. It makes them 2 to 3 times more transparent according to the researchers that have studied this, and means that they enter a sort of a state of torpor. Now, in the article I read, this is described as a magic trick and it is a really risky, dangerous thing to do for a whole host of reasons.
Flora Graham
When I saw this when I was writing it up for the Briefing, I was just thinking this is amazing. This is like a cloaking device this thing has, and when you see it, basically when it's totally relaxed as opposed to basically what the researchers just did, then they got them like all worked up. Like not in a mean way, just like got them all warmed up and excited. You can see the body changes so much. It's definitely one that's worth googling to see how those images contrast.
Noah Baker
Absolutely. All these red blood cells, they squish them into this tiny pea-sized liver, which means that all that’s running around the blood vessels then is a very small number of red blood cells, but plasma otherwise, which is just essentially clear, with a slight bluish tinge. And that means that it's really hard to work out the outline of the frog anymore. And even the liver itself is also disguised. It's coated with these reflective crystals, which give it a kind of a shiny white look. It's absolutely fascinating. Now, this is also hard to do, right, because organs need oxygen, so they have to enter this kind of precarious state where all their organs go into kind of a hyper dormant mode, so they don't need to use that oxygen. But also, packing that many red blood cells into that small of a space should cause catastrophic clotting. I mean, that couldn't happen in a human but the frogs seem to manage it okay, and scientists honestly don't have a clue how they're managing to do it. Not only that, but it takes only a couple of seconds for the blood to reperfuse around the body when they wake up and walk around. As soon as they wander around, blood just pushes out and it's all just fine again. Completely baffling.
Host: Benjamin Thompson
I think glass frogs might be one of my favourite animals up there now with the mimic octopus. That is something else.
Noah Baker
It's super cool. Also, interestingly, they're the only animals that seem to have managed to pull off this transparency trick on land. In water, it's more common. It's still not very common, but it's easier to appear transparent with a fluid-filled body inside fluid, but, on land, much more difficult to do. And these glass frogs have really taken it to the extreme. And as a lapsed zoologist from my early times, this was very exciting when I saw it in your Briefing, Flora. And I actually saw it just before another story, which is a completely different story, but I also thought I really wanted to talk about it because it's a really meaningful moment, which is that there has been an announcement of what will replace a statue of Robert E Lee, a confederate general, that was toppled in 2020 during the Black Lives Matter protests in Roanoke, Virginia. It’s going to be replaced by a statue of Henrietta Lacks, which is a really significant moment historically, and it’s significant for science as well that she's being represented in this way.
Host: Benjamin Thompson
Of course, Henrietta Lacks is an astonishingly important figure in science who was essentially completely unknown for so, so long. Tell us about her, Noah, for people who maybe aren't familiar.
Noah Baker
Indeed, she was a tobacco farmer. She was an African American woman, and she sadly died when she was in her early 30s of cervical cancer. However, some of her cancer cells were harvested without her permission and became the first cells that were cloned outside of the human body. And that line of cells, which were known as HeLa cells, became really fundamentally important in the development of many, many, many biomedical advances, from IVF, to cancer treatment to AIDS research. However, fundamentally, this was all based on a massive injustice, which was the use of someone's biological material without their consent, without their knowledge even. And there’s been a real push for a long time by Henrietta Lacks’ family to try to raise awareness of her, her contributions to science, and also to try to acknowledge the fact that she has been erased in such a significant way. And I think this statue being erected, which isn't the first statue that's been erected – there was also one erected at the University of Bristol in the UK – but it's a really significant step along this very long process of trying to counteract the erasure of Henrietta Lacks to ensure that people are aware of the contribution that she has made to science and to medical research.
Flora Graham
And this new statue is actually in her hometown. That's why it's such an apt location for this to be placed. And her family had said previously that this allows her to maybe represent so many people, especially African American people in the United States, who were participants in all sorts of medical trials and other experiences at a time when knowledge and consent was not considered a part of the deal.
Noah Baker
Indeed, and the funds for this statue were raised by a group called Roanoke Hidden Histories, which is an organisation dedicated to elevating African American contributions to culture, to society, to science. And this was also really significant because this is in place of a statue of Robert E Lee, who was a confederate general, that was toppled. And there were strong calls at the time to replace that statue with something which represented African American contributions which have otherwise been erased. And so, there's a series of reasons that this is a really meaningful announcement that's been made here.
Host: Benjamin Thompson
And we've got a few articles about the life and contributions of Henrietta Lacks over on nature.com/news, and we'll put links to those in the show notes. But I think we've got time for one more, Noah and Flora. Let's round the show out. Flora, anything else that stood out to you in the Nature Briefing in the last few days and weeks?
Flora Graham
Well, this was a story that kind of answered a question that I thought I already knew the answer to because I've seen Jurassic Park, which is, what do dinosaurs sound like? I mean, we all know, right?
Noah Baker
Absolutely. If it’s a velociraptor, it's really easy. We know that. Everyone knows that.
Flora Graham
Well, apparently Jurassic Park is not 100% accurate in every way because the question, what do dinosaurs sound like, is actually very much an open question. There is, in fact, very little fossil evidence of any kind of fossilised vocal structures from big dinosaurs like Tyrannosaurus rex, so no larynx, no voice box. And there is a question because we now have found some evidence of vocal material and fossils from very early birds that these physical elements can be fossilised. So, why haven't we found any for dinosaurs? So, that has led scientists to hypothesise that maybe dinosaurs, in fact, didn’t roar. Maybe they made sounds more like the closed mouth vocalisations of birds. And when I heard of like how a dove would coo maybe, imagine a Tyrannosaurus rex with that closed mouth cooing sound. I just think that's such a fantastic kind of audio image.
Noah Baker
I adore it. We've got a cooing or clucking sort of dinosaur. How glorious that would be.
Flora Graham
Exactly, and there's other structures, like the hadrosaur has this big hollow head crest. And we've all, I'm sure, imagined some nice honking and hooting sounds from the hadrosaur. But take away some of the actual vocalisation from that and you get a sound that some simulations have shown to be absolutely unlike anything we might have heard before, something scientists describe as ‘otherworldly’.
Host: Benjamin Thompson
That's amazing. I mean, there's so many questions, obviously, about dinosaurs, like, what colour were they? And there's been some sort of fossil evidence of potential pigments, that sort of thing, right? And then, what did they sound like, which is, of course, an impossible question to answer definitively. And yet, scientists are making their best guess based on remaining anatomy or remaining fossils.
Flora Graham
Absolutely. And I think we look to birds, modern birds, and how they can give us hints as to what came before. And the sound making structures can involve lots of kind of hollow cavities in the head and things like that, that really are quite different from what we might see in water reptiles, for example, or certainly in modern mammals that we maybe spend most of our time making sounds to, such as in this podcast.
Host: Benjamin Thompson
And you said that scientists haven't found any evidence of vocal cords or of a voice box or what have you. But I guess absence of evidence isn't evidence of absence, right? Like could it be that we just haven't found one yet and that the T. rex would roar like you might imagine in a Hollywood movie?
Flora Graham
That's the thing with fossils, it's a wonder that we find so much amazing stuff that we do, and these are considered soft tissues, so they are much less likely to be preserved. I think that's why it was so interesting for scientists when they found the vocalisation organs of ancient birds because that showed that it is possible for these things to be fossilised. So, the wonderful article I put in the Briefing from BBC Future, which is a good long read, that's why they really start to look at some of these very complete and amazing Tyrannosaurus rex fossils. And scientists were able to really look at that and say, like, what are the missing pieces here? What might that indicate about how this creature really lived?
Noah Baker
Fascinating. I genuinely love what palaeontologists can find out about these ancient dinosaurs. Even by the lack of an apparatus, we can get to cooing. How wonderful.
Host: Benjamin Thompson
Right, well, let's leave it there then team, I think. Thank you both so much for joining me. And Flora, before we go, why don't you tell people where they can get more stories like this but delivered to their inbox in email form, let’s say?
Flora Graham
That's right. I'll be happy to email you great stuff like this every day if you sign up at nature.com/briefing.
Host: Benjamin Thompson
Well, Flora and Noah, thank you both so much for joining me. This has been the latest edition of ichthyosaur… of the Nature Podcast. I can’t wait to have you back on the show again soon.
Noah Baker
Thanks so much. It’s been great being here.
Flora Graham
Thanks, Ben.